KR102700222B1 - Polishing pad and preparing method of semiconductor device using the same - Google Patents

Abstract

The present invention relates to a polishing pad which can provide properties suitable for various polishing purposes for various polishing targets through a segmented structural design in the thickness direction, and which can secure environmental friendliness by applying regenerative or recyclable materials to at least some of its components, unlike existing polishing pads, with respect to disposal after use. Specifically, the polishing pad includes a polishing layer, wherein the polishing layer includes: a polishing variable layer having a polishing surface; and a polishing constant layer disposed on the back side of the polishing surface of the polishing variable layer, wherein a ratio of Shore D hardnesses of the polishing variable layer and the polishing constant layer may be 0.50 to 1.50.

Description

{POLISHING PAD AND PREPARING METHOD OF SEMICONDUCTOR DEVICE USING THE SAME}

It relates to pads applied in a polishing process and to a technology for applying such pads to a method for manufacturing semiconductor devices.

Chemical Mechanical Planarization (CMP) or Chemical Mechanical Polishing (CMP) process can be performed for various purposes in various technical fields. The CMP process is performed on a predetermined polishing surface of a polishing target, and can be performed for the purposes of planarizing the polishing surface, removing agglomerated materials, resolving crystal lattice damage, and removing scratches and contaminants.

The classification of CMP process technology in semiconductor processes can be classified by the target film texture or the surface shape after polishing. For example, it can be divided into single silicon or poly silicon depending on the target film texture of polishing, and it can be classified into various oxide films or metal films such as tungsten (W), copper (Cu), aluminum (Al), ruthenium (Ru), and tantalum (Ta) depending on the type of impurity. In addition, it can be classified into a process for alleviating the roughness of the substrate surface, a process for flattening steps caused by multilayer circuit wiring, and an element separation process for selectively forming circuit wiring after polishing depending on the surface shape after polishing.

The CMP process can be applied multiple times in the manufacturing process of semiconductor devices. In the case of semiconductor devices, multiple layers are included, and each layer includes a complex and fine circuit pattern. In addition, semiconductor devices have recently evolved in the direction of reducing the size of individual chips and making the patterns of each layer more complex and fine. Accordingly, the purpose of the CMP process has expanded to include not only the purpose of planarizing circuit wiring in the manufacturing process of semiconductor devices, but also the application of circuit wiring separation and wiring surface improvement, and as a result, more precise and reliable CMP performance is required.

The polishing pad used in this CMP process is a process component that processes the polishing surface to the required level through friction, and can be considered one of the most important factors in terms of thickness uniformity of the polishing target after polishing, flatness of the polishing surface, and polishing quality.

In one embodiment of the present invention, it is intended to provide a polishing pad capable of providing properties suitable for various polishing purposes for various polishing targets through a segmented structural design in the thickness direction, and having no deterioration in long-term polishing performance based on appropriate variability in structural changes during a polishing process. In addition, with respect to disposal of the polishing pad after use, unlike existing polishing pads, it is intended to achieve an environmentally friendly purpose by applying regenerative or recyclable materials to at least some of the components.

In another embodiment of the present invention, the present invention provides a method for manufacturing a semiconductor device using the polishing pad, which can secure diversity of surfaces to be polished of a semiconductor substrate, secure an appropriate polishing rate for each surface to be polished, and at the same time ensure excellent polishing flatness and the lowest level of defect occurrence, and further provides a method for manufacturing a semiconductor device that entails improved results in terms of process productivity and economy.

In one embodiment, a polishing pad is provided, which includes a polishing layer, the polishing layer including: a polishing variable layer having a polishing surface; and a polishing constant layer disposed on a back side of the polishing surface of the polishing variable layer, wherein a ratio of shore D hardnesses of the polishing variable layer and the polishing constant layer is from 0.50 to 1.50.

The above polishing variable layer may be 30% to 60% by volume of the total volume of the polishing layer.

The first polishing variability index of the above polishing variable layer according to Equation 1 below may be 0.1 to 11.0.

[Formula 1]

In the above Equation 1, Ri is the surface roughness (Ra) of the polishing surface at the time point of introduction of the life of the polishing variable layer, Rf is the surface roughness (Ra) of the polishing surface at the time point of termination of the life of the polishing variable layer, Ti is the total thickness of the polishing pad at the time point of introduction of the life of the polishing variable layer, and Tf is the total thickness of the polishing pad at the time point of termination of the life of the polishing variable layer.

The above polishing variable layer may include at least one groove having a depth smaller than the total thickness of the polishing variable layer or equal to the total thickness of the polishing variable layer on the polishing surface, and a second polishing variability index of the polishing variable layer according to the following Equation 2 may be 0.1 to 3.5.

[Formula 2]

In the above equation 2, Ri is the surface roughness (Ra) of the polishing surface at the time point of introduction of the life of the polishing variable layer, Rf is the surface roughness (Ra) of the polishing surface at the time point of termination of the life of the polishing variable layer, Gi is the depth of the groove at the time point of introduction of the life of the polishing variable layer, and Gf is the depth of the groove at the time point of termination of the life of the polishing variable layer.

The above polishing variable layer may include at least one groove having a depth smaller than the total thickness of the polishing variable layer or equal to the total thickness of the polishing variable layer on the polishing surface, and a depth change rate (%) of the groove according to the following Equation 3 may be 20% to 100%.

[Formula 3]

In the above equation 3, Gi is the groove depth at the time of introduction of the life of the polishing variable layer, and Gf is the groove depth at the time of termination of the life of the polishing variable layer.

The above polishing pad may have a Shore D hardness of 45 to 70 for the entire laminate.

The ratio of the Shore D hardness of the entire polishing pad laminate to the Shore D hardness of the polishing layer may be 0.95 to 1.10.

The above-mentioned polishing variable layer may include a thermosetting resin, and the above-mentioned polishing constant layer may include a thermoplastic resin.

The above polishing variable layer may include a cured product of a preliminary composition including a urethane-based prepolymer.

The above-mentioned abrasive invariant layer may include one selected from the group consisting of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), thermoplastic polyurethane (TPU), and combinations thereof.

In another embodiment, a method for manufacturing a semiconductor device is provided, comprising: providing a polishing pad including a polishing layer having a polishing surface on a platen; arranging a surface to be polished of a target object to be polished so that the polishing surface is in contact with the polishing surface, and then rotating the polishing pad and the target object relative to each other under a pressurized condition to polish the target object; wherein the polishing layer includes a polishing variable layer including the polishing surface, and a polishing constant layer arranged on a back side of the polishing surface of the polishing variable layer, and a ratio of shore D hardnesses of the polishing variable layer and the polishing constant layer is 0.50 to 1.50.

The load applied to the polishing surface of the polishing layer of the above-mentioned polishing target may be 0.01 psi to 20 psi.

The above polishing pad can provide properties suitable for various polishing purposes for various polishing targets through a detailed structural design in the thickness direction, and can implement an effect in which long-term polishing performance does not deteriorate based on appropriate variability in structural change during the polishing process. In addition, the above polishing pad can secure environmental friendliness by applying regenerative or recyclable materials to at least some of its components, unlike existing polishing pads, with respect to disposal after use.

The above method for manufacturing a semiconductor device is a method that applies the above polishing pad, and can secure diversity of the polishing surface of a semiconductor substrate, secure an appropriate polishing rate for each polishing surface, and at the same time, ensure excellent polishing flatness and the lowest level of defect occurrence, and furthermore, can produce improved results in terms of process productivity and economy.

Figure 1 schematically illustrates a cross-section of the polishing layer according to one embodiment.
Figure 2 schematically illustrates changes in the polishing process of the polishing surface according to one embodiment.
Figure 3 schematically illustrates a cross-section of the polishing pad according to one embodiment.
Figure 4 is a schematic diagram illustrating a method for manufacturing the semiconductor device according to one embodiment.

The advantages and features of the present invention, and the methods for achieving them, will become clear with reference to the embodiments or examples described below. However, the present invention is not limited to the embodiments or examples disclosed below, but may be implemented in various different forms. The embodiments or examples specified below are provided only to make the disclosure of the present invention complete and to inform those skilled in the art of the scope of the invention, and the scope of the rights of the present invention is defined by the scope of the claims.

In the drawings, the thickness of some components is enlarged to clearly express layers or regions, if necessary. Also, in the drawings, the thickness of some layers and regions is exaggerated for convenience of explanation. The same reference numerals refer to the same components throughout the specification.

When a part such as a layer, film, region, or board is said to be "on" or "above" another part in this specification, this is interpreted to include not only the case where it is "directly above" another part, but also the case where there is another part in between. When a part is said to be "directly above" another part, this is interpreted to mean that there is no other part in between. In addition, when a part such as a layer, film, region, or board is said to be "under" or "below" another part, this is interpreted to include not only the case where it is "directly below" another part, but also the case where there is another part in between. When a part is said to be "directly below" another part, it is interpreted to mean that there is no other part in between.

In indicating a numerical range in this specification, the meaning of '~ or more' is interpreted to include the corresponding number or more cases. For example, '2 or more' means two or more cases. In addition, the description of 'X to Y' for a numerical range is interpreted as a range that includes X or Y. For example, '25 to 50' means a numerical range that includes 25 and 50.

Hereinafter, exemplary implementation examples according to the present invention will be described in detail.

In one embodiment of the present invention, a polishing pad including a polishing layer is provided. The polishing layer may include a polishing variable layer having a polishing surface; and a polishing constant layer disposed on a back side of the polishing surface of the polishing variable layer, and a ratio of Shore D hardness of the polishing variable layer to the Shore D hardness of the polishing constant layer may be 0.50 to 1.50.

Figure 1 schematically illustrates a cross-section in the thickness direction of the polishing layer (10) according to one embodiment. Hereinafter, the terms 'polishing surface' and 'first surface' may be used as terms referring to the same configuration.

Referring to FIG. 1, the polishing layer (10) may include the polishing variable layer (101) having the polishing surface (11). In addition, the polishing layer (10) may include the polishing constant layer (102) provided to support the polishing variable layer (101). The polishing constant layer (102) may be detachably bonded to the polishing variable layer (101). Each of the polishing variable layer (101) and the polishing constant layer (102) may include at least one layer.

In another aspect, the polishing layer (10) includes a first surface (11) which is a polishing surface and a second surface (12) which is a back surface thereof. In addition, the polishing layer (10) includes at least one separable interface (13) between the first surface (11) and the second surface (12). In this specification, the 'separable interface' means a boundary surface which can distinguish two adjacent layers based on this as a substantially discontinuous structure rather than a continuous structure. For example, the separable interface is a boundary surface which is detached or separated by a predetermined external force, and may correspond to an attachment surface using an adhesive layer as a medium.

In the above polishing layer (10), the ratio of the Shore D hardness of the polishing variable layer (101) and the polishing constant layer (102) may be about 0.50 to about 1.50. In another aspect, in the polishing layer (10), the ratio of the Shore D hardness of two adjacent layers with respect to the separable interface (13) may be about 0.50 to about 1.50. FIG. 1 illustrates, by way of example, a case where the separable interface (13) between the first surface (11) and the second surface (13) is one. Referring to this, the ratio of the Shore D hardness of two adjacent layers (101, 102) with respect to the separable interface (13) may be about 0.50 to about 1.50. The ratio of the Shore D hardness may be, for example, about 0.50 to about 1.50, for example, about 0.60 to about 1.50, for example, about 0.70 to about 1.40, for example, about 0.80 to about 1.20. The ratio of the Shore D hardness is sufficient if only one of the ratios of the hardness (Da) of one layer to the hardness (Db) of the other layer (Db/Da); and the ratio of the hardness (Da) of one layer to the hardness (Db) of the other layer (Da/Db); falls within the above range, and the desired technical effect can be achieved not only when both of them satisfy the above range, but also when only one of the two satisfies the ratio within the above range.

In one embodiment, the ratio of the Shore D hardness (H2) of the abrasive constant layer to the Shore D hardness (H1) of the abrasive variable layer (H2/H1) can be from about 0.5 to about 1.0, for example, from about 0.7 to about 1.0, for example, from about 0.8 to 1.0.

In one embodiment, the ratio of the Shore D hardness (H1) of the abrasive variable layer to the Shore D hardness (H2) of the abrasive constant layer (H1/H2) can be from about 1.0 to about 1.5, for example, from about 1.0 to about 1.4, for example, from about 1.0 to 1.2.

The above polishing pad can be utilized in polishing processes for various purposes. For example, the above polishing pad can be applied to a semiconductor device manufacturing process. Recently, semiconductor devices required have high integration and their structures are becoming three-dimensionally complex. In order to meet these demands, fine process control is essential in the manufacturing process of the semiconductor device. Semiconductor devices include various materials and various shapes of thin films, and a polishing process in which process conditions are finely adjusted is required according to the material and shape of each thin film. The polishing pad is one of these fine process control elements, and the polishing results of the semiconductor device can vary significantly even by slight differences in the structure, material, and shape of the polishing pad.

In the polishing pad including the polishing layer (10), the physical properties derived from the overall structural and/or compositional characteristics thereof are transferred to the polishing surface of the polishing target through the polishing surface (11). At this time, in the polishing layer (10), since the ratio of the Shore D hardness of the two adjacent layers (101, 102) with respect to the separable interface (13) satisfies the above-described range, the polishing properties transferred to the polishing surface of the polishing target through the polishing surface (11) can secure optimal conditions for implementing the intended polishing performance of the semiconductor device.

Referring to FIG. 1, the polishing layer (10) may include at least one polishing variable layer (101) which is a region from the polishing surface (11) to the separable interface (13); and at least one polishing constant layer (102) which is a region from the separable interface (13) to the second surface (12). In the present specification, the 'polishing variable layer' means a region in which physical characteristics such as structure and shape and/or chemical characteristics such as composition change during a polishing process using the polishing pad, and the 'polishing constant layer' means a region in which physical and/or chemical characteristics do not substantially change during a polishing process using the polishing pad. The meaning of 'substantially not changing' may be interpreted to include not only a case in which the physical and/or chemical characteristics do not change at all, but also a case in which the physical and/or chemical characteristics may change somewhat due to polishing in a pressurized environment and a wet environment, but are significantly changed compared to the polishing variable layer and can be considered as not substantially changed.

FIG. 1 illustrates an example in which the separable interface (13) is one, but if necessary, the polishing layer (10) may include at least two separable interfaces (13) between the polishing surface (11) and the second surface (12). In this case, the polishing variable layer (101) or the polishing constant layer (102) may each include multiple layers.

Since the above polishing layer (10) is designed to include at least one of the above polishing variable layers (101) and at least one of the above polishing constant layers (102), a precise structural design in the thickness direction is possible, and as a result of the organic interaction of the properties of each layer laminated in the thickness direction, the polishing performance produced through the above polishing surface (11) can be finely and precisely controlled according to the purpose.

In one embodiment, the polishing variable layer (101) may be about 30 vol % to about 60 vol % of the total volume of the polishing layer (10), for example, about 40 vol % to about 60 vol %, for example, about 45 vol % to about 55 vol %. By satisfying the above range for the volume of the polishing variable layer (101) in the total volume of the polishing layer (10), it is possible to secure the above-described technical advantages of the polishing variable layer (101) and the polishing constant layer (102), while advantageously implementing the process life of the polishing pad at the target level.

In one embodiment, the polishing variable layer may have a first polishing variability index of about 0.1 to about 11.0 according to Equation 1 below.

[Formula 1]

In the above Equation 1, Ri is the surface roughness (Ra) of the first surface at the time point of introduction of the life of the polishing variable layer, Rf is the surface roughness (Ra) of the first surface at the time point of termination of the life of the polishing variable layer, Ti is the total thickness of the polishing pad at the time point of introduction of the life of the polishing variable layer, and Tf is the total thickness of the polishing pad at the time point of termination of the life of the polishing variable layer.

The above-described polishing variable layer (101) has a predetermined lifespan in terms of providing a target level of polishing performance as a region in which physical properties and/or chemical properties change during a polishing process using the polishing pad, as described above. The introduction point of the lifespan of the polishing variable layer (101) means any point in time between the time the polishing variable layer; or the polishing pad is manufactured and before it is applied to the process. In addition, the end point of the lifespan of the polishing variable layer (101) means the time when the polishing variable layer (101) no longer implements polishing performance and thus the polishing variable layer; or the entire polishing pad needs to be replaced. For example, the end point of the lifespan can be defined as the time when the polishing rate of the polishing surface of the polishing target changes by 20% compared to the initial polishing rate within 1 hour after the start of polishing. That is, the initial polishing rate is a polishing rate value measured within 1 hour after the start of polishing on the polished surface, and the end of life time can be defined as a time point at which the polishing rate on the polished surface increases by 20% or decreases by 20% compared to the initial polishing rate.

The above first polishing variability index is composed of the surface roughness (Ri, Rf) of the polishing variable layer (101) at the start and end of its life, respectively, and the total thickness (Ti, Tf) of the polishing pad (110). The first polishing variability index by the above formula 1 can function as an indicator representing the variability performance of the polishing variable layer (101). That is, when the value of the above formula 1 of the polishing variable layer represents the above-mentioned range, that is, the range of about 0.1 to about 11.0, the polishing variable layer has a corresponding variability, and thus, when applied as a part of the polishing layer (10), it can continuously and uniformly exhibit structural features optimized for polishing efficiency throughout its life.

In one embodiment, the first polishing variability index can be from about 0.1 to about 11.0, for example, from about 0.1 to about 9.0, for example, from about 0.2 to about 9.0, for example, from about 0.2 to about 8.5, for example, from about 0.2 to about 8.0, for example, from about 0.2 to about 7.5, for example, from about 0.5 to about 7.5, for example, from about 0.8 to about 7.5, for example, from about 0.9 to about 7.5, for example, from about 1.0 to about 6.0, for example, from about 1.8 to 3.5, for example, from about 1.8 to 2.5.

The above Ti may have a thickness of, for example, about 800 μm to about 5000 μm, for example, about 1000 μm to about 4000 μm, for example, about 1000 μm to about 3000 μm, for example, about 1500 μm to about 3000 μm, for example, about 1700 μm to about 2700 μm, for example, about 2000 μm to about 3500 μm, but is not limited thereto.

The above Ri may be, for example, about 5 μm to about 15 μm, for example, about 5 μm to about 12 μm, for example, about 5 μm to about 10 μm, but is not limited thereto.

In one embodiment, when the Ti and Ri each satisfy the above-described ranges, and at the same time the first polishing variability index satisfies the above-described ranges, it may be more advantageous in terms of implementing excellent polishing performance due to the structural characteristics of the polishing variability layer (101).

In one embodiment, the polishing variable layer (101) may include at least one groove (Groove, 14) having a depth (d1) smaller than or equal to the total thickness (D1) of the polishing variable layer (101) on the polishing surface (11). The groove (14) may control the fluidity of the polishing liquid or polishing slurry supplied onto the polishing surface (11) during a polishing process using the polishing pad, or may control the size of the area where the polishing surface (11) and the polishing target surface directly contact each other, thereby appropriately implementing physical polishing characteristics.

For example, the polishing pad (110) may include a plurality of grooves (14) on the polishing surface (11). In one embodiment, the planar shape of the polishing pad (110) may be substantially circular, and the plurality of grooves (14) may have a concentric structure spaced apart from a predetermined interval from the planar center of the polishing pad (110) toward the end. In another embodiment, the plurality of grooves (14) may have a radial structure continuously formed from the planar center of the polishing pad (110) toward the end. In yet another embodiment, the plurality of grooves (14) may include both concentric grooves and radial grooves.

In the polishing variable layer (101) which is a region from the polishing surface (11) to the separable interface (13), when the polishing surface (11) includes at least one groove (14), the second polishing variability index of the polishing variable layer (101) according to the following equation 2 may be about 0.1 to about 3.5.

[Formula 2]

In the above Equation 2, Ri is the surface roughness (Ra) of the first surface at the time point of introduction of the life of the polishing variable layer, Rf is the surface roughness (Ra) of the first surface at the time point of termination of the life of the polishing variable layer, Gi is the depth of the groove at the time point of introduction of the life of the polishing variable layer, and Gf is the depth of the groove at the time point of termination of the life of the polishing variable layer.

The description of the introduction point of the life and the end point of the life of the above polishing variable layer (101) is as described above with respect to the first polishing variability index by the above formula 1. When the second polishing variability index of the above polishing variable layer (101) satisfies the above-mentioned range, the polishing variable layer (101) can provide a structure optimized in terms of the fluidity of the polishing liquid or polishing slurry, and the direct contact area on the first surface provided to the polishing surface is secured at an appropriate level, which can be more advantageous in securing a polishing rate in the target range.

In one embodiment, the second polishing variability index can be from about 0.1 to about 3.5, for example, from about 0.1 to about 3.3, for example, from about 0.1 to about 3.0, for example, from about 0.1 to about 2.0, for example, from about 0.3 to about 1.8, for example, from about 0.5 to about 1.5, for example, from about 0.5 to about 1.2, for example, from about 0.5 to 1.0, for example, from about 0.6 to about 1.0.

The above Gi may be, for example, about 600 μm to about 900 μm, for example, about 650 μm to about 900 μm, for example, about 700 μm to about 900 μm, but is not limited thereto.

In one embodiment, when the Ri and Gi each satisfy the above-described ranges, and at the same time the second polishing variability index satisfies the above-described ranges, it may be more advantageous in terms of implementing polishing performance by the structural features of the polishing variability layer (101).

In one embodiment, the polishing variable layer (101) can have the first polishing variability index and the second polishing variability index each simultaneously satisfy the above-described range. When the first polishing variability index and the second polishing variability index each satisfy the above-described range, the polishing variable layer (101) can have structural characteristics optimized for polishing efficiency as a part of the polishing layer (10), and in particular, can provide a structure optimized in terms of the fluidity of the polishing liquid or polishing slurry, and can secure an appropriate level of direct contact area on the first surface provided to the surface to be polished, which can be more advantageous in securing a polishing rate in the target range. Furthermore, it can be more advantageous in implementing constant polishing performance so that the above-described advantage is maintained throughout its life.

When the above polishing surface (11) includes at least one groove (14) having a depth smaller than or equal to the total thickness of the above polishing variable layer (101), the depth change rate (%) of the groove (14) according to the following equation 3 in the above polishing variable layer (101) may be about 20% to about 100%.

[Formula 3]

In the above equation 3, Gi is the groove depth at the time of introduction of the life of the polishing variable layer (101), and Gf is the groove depth at the time of end of the life of the polishing variable layer (101).

The introduction and end points of the life of the above polishing variable layer (101) and the matters relating to Gi and Gf are all the same as those described above with respect to the second polishing variable index.

In one embodiment, the groove depth change rate according to the above formula 3 can be from about 20% to about 80%, for example, from about 30% to about 80%, for example, from about 40% to about 80%, for example, from about 45% to about 75%, for example, from about 50% to about 70%.

Referring to FIG. 1, the depth (d1) of the groove (14) changes during the polishing process from the depth (Gi) at the time of introduction of the life to the depth (Gf) at the time of termination of the life. Specifically, the depth (d1) of the groove (14) gradually becomes shallower as the polishing surface (11) is worn away as the polishing surface (11) and the polishing target surface are polished through physical contact with each other. At this time, the value of the equation 3, which has as elements the depth (Gi) of the groove at the time of introduction of the life and the depth (Gf) of the groove at the time of termination of the life, can satisfy the aforementioned range only when the physical characteristics of the polishing variable layer (101), such as elongation, tensile strength, and hardness, are appropriately supported. Specifically, if the physical properties of the polishing variable layer (101) are not properly supported, the shallower the groove depth (d1) becomes, the greater the influence of changes in the fluidity of the polishing slurry, etc., on the polishing performance, which may rapidly deteriorate the overall polishing performance. The polishing variable layer (101) according to one embodiment can exhibit optimal physical properties corresponding thereto by satisfying the above-mentioned range of the value of the above-mentioned Equation 3, and based on this, even if the groove depth (d1) becomes shallow, the influence thereof on the polishing performance can be minimized, thereby implementing excellent polishing performance throughout the entire polishing process. In addition, as the usage period of the polishing variable layer (101) is maximized, the effect of extending the life of the polishing pad can be obtained.

Referring to FIG. 1, the width (w1) of the groove (14) can affect the size of the physical contact area between the polishing surface (11) and the target polishing surface of the polishing object during the polishing process. Accordingly, the width (w1) of the groove (14) can be appropriately designed to implement the required polishing performance depending on the type of the polishing object; the type of the polishing liquid or polishing slurry; and the intended polishing performance. For example, the width (w1) of the groove (14) can be about 0.2 mm to about 1.0 mm, for example, about 0.3 mm to about 0.8 mm, for example, about 0.4 mm to about 0.7 mm, for example, about 0.4 mm to about 0.6 mm.

When the above-described polishing variable layer (101) includes a plurality of grooves (14) on the above-described polishing surface (11), the pitch (pitch, p1) of the grooves (14), which is defined as the space between two adjacent grooves (14), may also be appropriately designed in the same context as the width (w1) of the grooves (14) to contribute to the implementation of the required polishing performance. For example, the pitch (p1) of the grooves (14) may be about 1.5 mm to about 5.0 mm, for example, about 1.5 mm to about 4.0 mm, for example, about 1.5 mm to about 3.0 mm.

The numerical ranges of the width (w1) and pitch (p1) of the groove above are structural configurations that are substantially unchanged during the polishing process, but, for example, each range may be a value measured based on the introduction time of the life of the polishing variable layer (101).

In one embodiment, the polishing variable layer (101) and the polishing constant layer (102) may be formed of different materials. It should be understood that the term "different materials" in this specification includes not only a case where there are no overlapping components at all, but also a case where the overall composition is different and thus recognized as a heterogeneous material even if some of the same components are included. By forming the polishing variable layer (101) and the polishing constant layer (102) of different materials, the physical properties along the thickness direction of the polishing pad can be designed more precisely and minutely, thereby enabling the implementation of polishing performance for various purposes of various applications.

In one embodiment, the polishing variable layer may include a thermosetting resin, and the polishing constant layer may include a thermoplastic resin. In this case, the physical properties along the thickness direction of the polishing pad can be designed more precisely and finely, thereby enabling the implementation of polishing performance for various purposes in various applications.

For example, the polishing variable layer (101) may include a cured product of a preliminary composition including a urethane-based prepolymer. In one embodiment, the cured product may be a thermosetting product. In one embodiment, the preliminary composition may further include a curing agent and a foaming agent. The 'prepolymer' refers to a polymer having a relatively low molecular weight in which the polymerization degree is stopped at an intermediate stage for easy molding in the production of a cured product. The prepolymer may be subjected to an additional curing process such as heating and/or pressurization on its own, or may be reacted by mixing with an additional compound such as another polymerizable compound, for example, a heterogeneous monomer or a heterogeneous prepolymer, and then molded into a final cured product.

In one embodiment, the urethane-based prepolymer can be prepared by reacting an isocyanate compound and a polyol compound.

The isocyanate compound used in the production of the above urethane-based prepolymer may be one selected from the group consisting of aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, and combinations thereof. For example, the isocyanate compound may include aromatic diisocyanate. For example, the isocyanate compound may include aromatic diisocyanate and alicyclic diisocyanate.

The above isocyanate compounds include, for example, 2,4-toluenediisocyanate (2,4-TDI), 2,6-toluenediisocyanate (2,6-TDI), naphthalene-1,5-diisocyanate, p-phenylenediisocyanate, tolidinediisocyanate, 4,4'-diphenylmethanediisocyanate, hexamethylenediisocyanate, dicyclohexylmethanediisocyanate, It may include one selected from the group consisting of 4,4'-dicyclohexylmethanediisocyanate (H ₁₂ MDI), isophorone diisocyanate, and combinations thereof.

The above 'polyol' means a compound containing at least two hydroxyl groups (-OH) per molecule. In one embodiment, the polyol compound may include a dihydric alcohol compound having two hydroxyl groups, i.e., a diol or glycol; or a trihydric alcohol compound having three hydroxyl groups, i.e., a triol compound.

The above polyol compound may include, for example, one selected from the group consisting of polyether polyol, polyester polyol, polycarbonate polyol, acrylic polyol, and combinations thereof.

The above polyol compound may include, for example, one selected from the group consisting of polytetramethylene ether glycol (PTMG), polypropylene ether glycol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, diethylene glycol (DEG), dipropylene glycol (DPG), tripropylene glycol, polypropylene glycol, polypropylene triol, and combinations thereof.

The polyol compound may have a weight average molecular weight (Mw) of about 100 g/mol to about 3,000 g/mol, for example, about 100 g/mol to about 2,000 g/mol, for example, about 100 g/mol to about 1,800 g/mol.

In one embodiment, the polyol compound may include a low molecular weight polyol having a weight average molecular weight (Mw) of about 100 g/mol or more and less than about 300 g/mol and a high molecular weight polyol having a weight average molecular weight (Mw) of about 300 g/mol or more and about 1800 g/mol or less. The weight average molecular weight (Mw) of the high molecular weight polyol may be, for example, about 500 g/mol or more and about 1800 g/mol or less, or may be, for example, about 700 g/mol or more and about 1800 g/mol or less. In this case, the polyol compound may form an appropriate crosslinking structure in the urethane-based prepolymer, and the polishing variable layer (101) formed by curing the preliminary composition including the urethane-based prepolymer under predetermined process conditions may be more advantageous in implementing the aforementioned effect.

The above urethane-based prepolymer may have a weight average molecular weight (Mw) of about 500 g/mol to about 3,000 g/mol, for example, about 600 g/mol to about 2,000 g/mol, for example, about 800 g/mol to about 1,000 g/mol. When the urethane-based prepolymer has a degree of polymerization corresponding to the above-described weight average molecular weight (Mw), the polishing variable layer (101) formed by curing the preliminary composition under predetermined process conditions may be more advantageous in implementing the above-described effect.

In one embodiment, the isocyanate compound for producing the urethane-based prepolymer may include an aromatic diisocyanate. The aromatic diisocyanate may include, for example, 2,4-toluene diisocyanate (2,4-TDI), and may include, for example, 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI). In addition, the polyol compound for producing the urethane-based prepolymer may include, for example, polytetramethylene ether glycol (PTMG) and diethylene glycol (DEG).

In another embodiment, the isocyanate compound for producing the urethane-based prepolymer may include an aromatic diisocyanate and an alicyclic diisocyanate. The aromatic diisocyanate may include, for example, 2,4-toluene diisocyanate (2,4-TDI), and may include, for example, 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI). The alicyclic diisocyanate may include, for example, 4,4'-dicyclohexyl methane diisocyanate (H ₁₂ MDI). In addition, the polyol compound for producing the urethane-based prepolymer may include, for example, polytetramethylene ether glycol (PTMG) and diethylene glycol (DEG).

In one embodiment, the total weight of the polyol compound may be from about 100 parts by weight to about 180 parts by weight, relative to 100 parts by weight of the total weight of the isocyanate compound, for example, greater than about 100 parts by weight and less than or equal to about 180 parts by weight, for example, from about 110 parts by weight to about 160 parts by weight, for example, from about 120 parts by weight to about 150 parts by weight.

In another embodiment, the total weight of the polyol compound may be greater than about 180 parts by weight and less than or equal to about 250 parts by weight, for example, from about 185 parts by weight to about 250 parts by weight, for example, from about 190 parts by weight to about 240 parts by weight, relative to 100 parts by weight of the total weight of the isocyanate compound.

In one embodiment, the polyol compound includes polytetramethylene ether glycol (PTMG), and the content of the polytetramethylene ether glycol (PTMG) can be from about 100 parts by weight to about 250 parts by weight relative to 100 parts by weight of the total weight of the isocyanate compound, for example, can be more than about 100 parts by weight and less than or equal to about 250 parts by weight, for example, can be from about 110 parts by weight to about 220 parts by weight, for example, can be from about 110 parts by weight to about 140 parts by weight.

In another embodiment, the polyol compound comprises polytetramethylene ether glycol (PTMG), and the content of the polytetramethylene ether glycol (PTMG) may be about 150 parts by weight to about 250 parts by weight, for example, about 180 parts by weight to about 230 parts by weight, relative to 100 parts by weight of the total weight of the isocyanate compound.

In one embodiment, the polyol compound comprises diethylene glycol (DEG), and the content of diethylene glycol (DEG) may be from about 1 part by weight to about 20 parts by weight relative to 100 parts by weight of the total weight of the isocyanate compound, for example, from about 1 part by weight to about 15 parts by weight.

In one embodiment, the isocyanate compound comprises the aromatic diisocyanate, and the aromatic diisocyanate comprises 2,4-TDI and 2,6-TDI, and the content of the 2,6-TDI can be about 1 part by weight to about 40 parts by weight relative to 100 parts by weight of the 2,4-TDI, for example, about 1 part by weight to about 30 parts by weight, for example, about 3 parts by weight to about 28 parts by weight, for example, about 20 parts by weight to about 30 parts by weight.

In another embodiment, the content of the 2,6-TDI may be about 1 part by weight to about 40 parts by weight relative to 100 parts by weight of the 2,4-TDI, for example, about 1 part by weight to about 30 parts by weight, for example, about 1 part by weight to about 20 parts by weight, for example, about 1 part by weight to about 10 parts by weight.

In one embodiment, the isocyanate compound includes the aromatic diisocyanate and the alicyclic diisocyanate, and the content of the alicyclic diisocyanate may be about 5 parts by weight to about 30 parts by weight relative to 100 parts by weight of the total aromatic diisocyanate, for example, about 10 parts by weight to about 25 parts by weight.

When the above-described preliminary composition satisfies the above-described compositional characteristics, the polishing variable layer (101) manufactured through the curing of the above-described preliminary composition can exhibit appropriate physical/mechanical properties, and the groove depth change rate according to the above-described formula 3 can contribute to the implementation of uniform polishing performance and maximization of the service life by satisfying the above-described range. In addition, based on the above-described physical/mechanical properties, it can be advantageous to implement excellent polishing performance by providing excellent rigidity and elasticity to the polishing target through the polishing surface (11).

The above preliminary composition may have an isocyanate group content (NCO%) of about 5 wt% to about 11 wt%, for example, about 5 wt% to about 10 wt%. In one embodiment, the isocyanate group content (NCO%) may be about 5 wt% to about 8.5 wt%, and in another embodiment, the isocyanate group content (NCO%) may be about 8.5 wt% to about 10 wt%. The 'isocyanate group content' refers to the percentage of the weight of the isocyanate group (-NCO) that is not subjected to urethane reaction and exists as a free reactor, among the total weight of the preliminary composition. The isocyanate group content (NCO%) of the preliminary composition may be designed by comprehensively controlling the type and content of the monomer for producing the urethane-based prepolymer, the process conditions such as temperature and pressure of the urethane-based prepolymer production process, and the type of the additive used in the production of the urethane-based prepolymer. When the above isocyanate group content satisfies the above range, the polishing variable layer (101) manufactured through curing of the preliminary composition is advantageous in securing appropriate physical/mechanical properties, and may be advantageous in providing excellent polishing performance to the polishing target through the polishing surface (11) by being applied in a laminated state with the polishing constant layer (102).

In one embodiment, the preparatory composition may further include a curing agent. The curing agent is a compound for chemically reacting with the urethane-based prepolymer to form a final cured structure within the polishing variable layer (101), and may include, for example, an amine compound or an alcohol compound. Specifically, the curing agent may include one selected from the group consisting of an aromatic amine, an aliphatic amine, an aromatic alcohol, an aliphatic alcohol, and combinations thereof.

For example, the curing agent may be selected from the group consisting of 4,4'-methylenebis(2-chloroaniline; MOCA), diethyltoluenediamine (DETDA), diaminodiphenylmethane, dimethyl thio-toluene diamine (DMTDA), propanediol bis p-aminobenzoate, methylene bis-methylanthranilate, diaminodiphenylsulfone, m-xylylenediamine, isophoronediamine, ethylenediamine, diethylenetriamine, triethylenetetramine, It may include one selected from the group consisting of polypropylenediamine, polypropylenetriamine, bis(4-amino-3-chlorophenyl)methane, and combinations thereof.

The above preliminary composition may contain about 18 parts by weight to about 27 parts by weight of the curing agent, for example, about 19 parts by weight to about 26 parts by weight, for example, about 20 parts by weight to about 26 parts by weight, based on 100 parts by weight of the total weight. When the content of the curing agent satisfies the above range, it may be more advantageous in implementing the intended performance of the polishing pad.

The molar ratio of the isocyanate group (-NCO) in the above-described preliminary composition to the reactive group in the above-described curing agent (NCO:reactive group) may be about 1:0.80 to about 1:1.20, for example, about 1:0.90 to about 1:1.10, for example, about 1:0.90 to about 1:1.00, for example, about 1:90 or more and less than about 1:1.00. The reactive group may vary depending on the type of the curing agent, but may be, for example, an amine group (-NH ₂ ) or a hydroxyl group (-OH). When the molar ratio of the isocyanate group in the above-described preliminary composition and the reactive group in the above-described curing agent satisfies the above-described range, an appropriate crosslinking structure can be formed by a chemical reaction between the urethane-based prepolymer in the above-described preliminary composition and the curing agent, and as a result, the polishing variable layer (101) secures physical/mechanical properties such as an appropriate level of tensile strength and elongation, and can transmit excellent polishing performance to the polishing surface of the polishing target through the polishing surface (11).

The above-described polishing variable layer (101) may be a porous structure including a plurality of pores (15). The plurality of pores (15) located on the uppermost surface of the polishing variable layer (101) may have at least a portion of their interiors exposed to the outside to provide a predetermined surface roughness to the polishing surface (11). FIG. 2 is a schematic diagram illustrating a structural change of the polishing surface (11) according to one embodiment during a polishing process. Specifically, FIG. 2 is a schematic diagram illustrating a structural change of some pores among the plurality of pores (15) whose interiors are exposed to the outside on the polishing surface (11) according to one embodiment during a polishing process. Referring to FIG. 2, since the plurality of pores (15) are dispersed throughout the polishing variable layer (101), even if the uppermost surface is gradually worn away during the polishing process through the polishing surface (11), they may contribute to continuously forming surface roughness. However, in the case of the pores (15) whose interiors are exposed on the polishing surface (11), as the polishing process is continued under a predetermined pressurized condition, the portion corresponding to the boundary between the polishing surface (11) and the pores (15) is physically pressed and deformed, and this phenomenon affects the change in the surface roughness of the polishing surface (11).

In one embodiment, the plurality of pores (15) included in the polishing variable layer (101) may have an average size of about 5 ㎛ to about 50 ㎛, for example, about 5 ㎛ to about 40 ㎛, for example, about 10 ㎛ to about 40 ㎛, for example, about 10 ㎛ to about 35 ㎛. Since the plurality of pores satisfy the above-described size, the first polishing variability index by the above-described formula 1 may be advantageously satisfied to satisfy the above range, and thus, may be advantageous in terms of implementing the target polishing performance itself and implementing uniform performance throughout the life of the polishing variable layer. The average size of the plurality of pores (15) is a two-dimensional value, and is based on the number average value of the pore diameter measured in a projection image taken using a photographing means such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM) based on the size of the pores exposed to the outside of one surface at the time of introduction of the life of the polishing variable layer (101).

The above-described preliminary composition may further include a foaming agent. The foaming agent may include one selected from the group consisting of a solid foaming agent, a gaseous foaming agent, a liquid foaming agent, and a combination thereof as a component for forming a pore structure within the polishing variable layer (101). In one embodiment, the foaming agent may include a solid foaming agent, a gaseous foaming agent, or a combination thereof.

The above-described solid foaming agent may include expandable particles. The expandable particles are particles having a property of being expandable by heat or pressure, etc., and the final pore size may be determined by heat or pressure applied during the process of manufacturing the polishing variable layer (101). The expandable particles may include thermally expanded particles, unexpanded particles, or a combination thereof. The 'thermally expanded' particles refer to particles that have been pre-expanded by heat, and which have little or no change in size due to heat or pressure applied during the process of manufacturing the polishing variable layer. The 'unexpanded' particles refer to particles that have not been pre-expanded, and which have been expanded by heat or pressure applied during the process of manufacturing the polishing layer, and which have a final size determined.

The average particle diameter of the above expandable particles may be from about 5 μm to about 200 μm, for example, from about 20 μm to about 50 μm, for example, from about 21 μm to about 50 μm, for example, from about 21 μm to about 40 μm. The average particle diameter of the above expandable particles may refer to the average particle diameter of the thermally expanded particles themselves in the case of thermally expanded particles, and may refer to the average particle diameter of the particles after being expanded by heat or pressure in the case of unexpanded particles.

The above expandable particles may include an outer shell made of a resin material; and an expansion-inducing component present in an interior enclosed in the outer shell.

For example, the outer shell may include a thermoplastic resin, and the thermoplastic resin may be at least one selected from the group consisting of a vinylidene chloride-based copolymer, an acrylonitrile-based copolymer, a methacrylonitrile-based copolymer, and an acrylic copolymer.

The above expansion-inducing component may include one selected from the group consisting of hydrocarbon compounds, chlorofluoro compounds, tetraalkylsilane compounds, and combinations thereof.

Specifically, the hydrocarbon compound may include one selected from the group consisting of ethane, ethylene, propane, propene, n-butane, isobutene, n-butene, isobutene, n-pentane, isopentane, neopentane, n-hexane, heptane, petroleum ether, and combinations thereof.

The above chlorofluoro compound may include one selected from the group consisting of trichlorofluoromethane (CCl ₃ F), dichlorodifluoromethane (CCl ₂ F ₂ ), chlorotrifluoromethane (CClF ₃ ), tetrafluoroethylene (CClF ₂ -CClF ₂ ), and combinations thereof.

The above tetraalkylsilane compound may include one selected from the group consisting of tetramethylsilane, trimethylethylsilane, trimethylisopropylsilane, trimethyl-n-propylsilane, and combinations thereof.

The solid foaming agent may optionally include inorganic component-treated particles. For example, the solid foaming agent may include inorganic component-treated expandable particles. In one embodiment, the solid foaming agent may include silica (SiO ₂ ) particle-treated expandable particles. The inorganic component-treated solid foaming agent may prevent agglomeration between the plurality of particles. The inorganic component-treated solid foaming agent may have different chemical, electrical, and/or physical properties of the foaming agent surface from the solid foaming agent that is not inorganic component-treated.

For example, the solid foaming agent may be present in an amount of about 0.5 parts by weight to about 10 parts by weight, for example, about 1 part by weight to about 3 parts by weight, for example, about 1.3 parts by weight to about 2.7 parts by weight, for example, about 1.3 parts by weight to about 2.6 parts by weight, based on 100 parts by weight of the urethane-based prepolymer.

The above-mentioned gaseous foaming agent may contain an inert gas. The above-mentioned gaseous foaming agent may be introduced during the process of reacting the urethane-based prepolymer and the curing agent and used as a pore-forming element.

The inert gas is not particularly limited in type as long as it is a gas that does not participate in the reaction between the urethane-based prepolymer and the curing agent, but may include, for example, one selected from the group consisting of nitrogen gas (N ₂ ), argon gas (Ar), helium gas (He), and combinations thereof. Specifically, the inert gas may include nitrogen gas (N ₂ ) or argon gas (Ar).

In one embodiment, the blowing agent may comprise a solid blowing agent. For example, the blowing agent may consist solely of a solid blowing agent.

The above-mentioned solid foaming agent comprises expandable particles, and the expandable particles may comprise heat-expanded particles. For example, the above-mentioned solid foaming agent may be composed only of heat-expanded particles. When the solid foaming agent comprises only heat-expanded particles without including the above-mentioned unexpanded particles, the variability of the pore structure is reduced, but the predictability in advance is increased, which may be advantageous in implementing uniform pore characteristics over the entire area of the above-mentioned polishing variable layer.

In one embodiment, the thermally expanded particles can be particles having an average particle diameter of about 5 μm to about 200 μm. The average particle diameter of the thermally expanded particles can be about 5 μm to about 100 μm, for example, about 10 μm to about 80 μm, for example, about 20 μm to about 70 μm, for example, about 20 μm to about 50 μm, for example, about 30 μm to about 70 μm, for example, about 25 μm to 45 μm, for example, about 40 μm to about 70 μm, for example, about 40 μm to about 60 μm. The average particle diameter is defined as the D50 of the thermally expanded particles.

In one embodiment, the density of the thermally expanded particles can be from about 30 kg/m3 to about 80 kg/m3, for example, from about 35 kg/m3 to about 80 kg/m3, for example, from about 35 kg/m3 to about 75 kg/m3, for example, from about 38 kg/m3 to about 72 kg/m3, for example, from about 40 kg/m3 to about 75 kg/m3, for example, from about 40 kg/m3 to about 72 kg/m3.

In one embodiment, the foaming agent may include a gaseous foaming agent. For example, the foaming agent may include a solid foaming agent and a gaseous foaming agent. The solid foaming agent is as described above.

The above-mentioned gaseous foaming agent may include nitrogen gas.

The above-described gaseous foaming agent may be injected through a predetermined injection line during the process in which the urethane-based prepolymer, the solid foaming agent, and the curing agent are mixed. The injection speed of the gaseous foaming agent may be about 0.8 L/min to about 2.0 L/min, for example, about 0.8 L/min to about 1.8 L/min, for example, about 0.8 L/min to about 1.7 L/min, for example, about 1.0 L/min to about 2.0 L/min, for example, about 1.0 L/min to about 1.8 L/min, for example, about 1.0 L/min to about 1.7 L/min.

The composition for manufacturing the above-mentioned polishing variable layer may further include other additives such as a surfactant, a reaction rate controlling agent, etc. The names 'surfactant', 'reaction rate controlling agent', etc. are names that are arbitrarily designated based on the main role of the corresponding substance, and each corresponding substance does not necessarily perform only the function limited to the role with the corresponding name.

The above surfactant is not particularly limited as long as it is a substance that prevents phenomena such as aggregation or overlapping of pores. For example, the surfactant may include a silicone-based surfactant.

The surfactant may be used in an amount of about 0.2 parts by weight to about 2 parts by weight based on 100 parts by weight of the urethane-based prepolymer. Specifically, the surfactant may be included in an amount of about 0.2 parts by weight to about 1.9 parts by weight, for example, about 0.2 parts by weight to about 1.8 parts by weight, for example, about 0.2 parts by weight to about 1.7 parts by weight, for example, about 0.2 parts by weight to about 1.6 parts by weight, for example, about 0.2 parts by weight to about 1.5 parts by weight, for example, about 0.5 parts by weight to 1.5 parts by weight, based on 100 parts by weight of the urethane-based prepolymer. When the surfactant is used in an amount within the above range, it may be advantageous for pores derived from the gas-phase foaming agent to be stably formed and maintained in the curing mold.

The above reaction rate regulator plays a role in promoting or retarding the reaction, and a reaction accelerator, a reaction retardant, or both can be used depending on the purpose.

The above reaction rate controlling agent may include a reaction accelerator. For example, the reaction accelerator may include one selected from the group consisting of a tertiary amine compound, an organometallic compound, and a combination thereof.

Specifically, the reaction rate modifier is triethylenediamine, dimethylethanolamine, tetramethylbutanediamine, 2-methyl-triethylenediamine, dimethylcyclohexylamine, triethylamine, triisopropanolamine, 1,4-diazabicyclo(2,2,2)octane, bis(2-methylaminoethyl) ether, trimethylaminoethylethanolamine, N,N,N,N,N''-pentamethyldiethylenetriamine, dimethylaminoethylamine, dimethylaminopropylamine, benzyldimethylamine, N-ethylmorpholine, N,N-dimethylaminoethylmorpholine, N,N-dimethylcyclohexylamine, 2-methyl-2-azanoboneine, dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dioctyltin diacetate, dibutyltin maleate, dibutyltin It may include one selected from the group consisting of di-2-ethylhexanoate, dibutyltin dimercaptide, and combinations thereof. In one embodiment, the reaction rate controlling agent may include one selected from the group consisting of benzyldimethylamine, N,N-dimethylcyclohexylamine, triethylamine, and combinations thereof.

The above reaction rate control agent can be used in an amount of about 0.05 parts by weight to about 2 parts by weight based on 100 parts by weight of the urethane-based prepolymer. Specifically, the reaction rate controlling agent may be used in an amount of from about 0.05 part by weight to about 1.8 part by weight, for example, from about 0.05 part by weight to about 1.7 part by weight, for example, from about 0.05 part by weight to about 1.6 part by weight, for example, from about 0.1 part by weight to about 1.5 part by weight, for example, from about 0.1 part by weight to about 0.3 part by weight, for example, from about 0.2 part by weight to about 1.8 part by weight, for example, from about 0.2 part by weight to about 1.7 part by weight, for example, from about 0.2 part by weight to about 1.6 part by weight, for example, from about 0.2 part by weight to about 1.5 part by weight, for example, from about 0.5 part by weight to about 1 part by weight, based on 100 parts by weight of the urethane-based prepolymer. When the above reaction rate controlling agent is used in the above range of contents, it may be advantageous to control the curing reaction rate of the second composition so that the polishing variable layer has pores of a desired size and hardness.

Since the above polishing variable layer (101) includes a cured product of the preliminary composition derived from an appropriately selected compound, polishing variability corresponding to the values of the above formulas 1 to 3 can be implemented, and together with other laminated structures such as the above polishing constant layer (102), in implementing the polishing performance of the overall polishing pad, appropriate physical/mechanical properties can be imparted, thereby deriving improved polishing results.

The above-described polishing constant layer (102) may be made of a different material from the polishing variable layer (101), as described above. For example, the polishing constant layer (102) may include a thermoplastic resin. In the case where the polishing constant layer (102) includes a thermoplastic resin, unlike the polishing variable layer (101) including a thermosetting resin, it may be more advantageous to achieve the desired physical/mechanical properties through the laminated structure of the polishing variable layer (101) and the polishing non-surface region (102), and by increasing the recyclability of some components of the polishing pad (110), it is possible to obtain the effect of improving not only the original polishing performance but also environmental friendliness.

The thermoplastic resin may include one selected from the group consisting of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), thermoplastic polyurethane (TPU), and combinations thereof.

In one embodiment, the thermoplastic resin may include a thermoplastic polyurethane (TPU). The TPU is not particularly limited, but may include, for example, a reaction product of an aromatic isocyanate component and a polyol component.

The above aromatic isocyanate component may include, for example, one selected from the group consisting of 2,4-toluenediisocyanate (2,4-TDI), 2,6-toluenediisocyanate (2,6-TDI), naphthalene-1,5-diisocyanate, p-phenylenediisocyanate, tolidinediisocyanate, 4,4'-diphenylmethanediisocyanate, and combinations thereof.

The above polyol compound may include, for example, one selected from the group consisting of polyether polyol, polyester polyol, polycarbonate polyol, acrylic polyol, and combinations thereof.

The polyol component of the thermoplastic resin may not include an alcohol compound having three or more hydroxyl groups (-OH) per molecule. In another aspect, the polyol component of the thermoplastic resin may be composed of a glycol having two hydroxyl groups (-OH) per molecule; or a diol compound.

The polyol component of the thermoplastic resin may have a weight average molecular weight (Mw) of about 80 g/mol to about 1000 g/mol, for example, about 90 g/mol to about 800 g/mol.

The above polyol compound may include, for example, one selected from the group consisting of polytetramethylene ether glycol (PTMG), polypropylene ether glycol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, diethylene glycol (DEG), dipropylene glycol (DPG), tripropylene glycol, polypropylene glycol, and combinations thereof.

In one embodiment, the thermoplastic resin can include a reaction product of a composition comprising a total of about 80 parts by weight to about 130 parts by weight of the polyol component, for example, about 80 parts by weight to about 80 parts by weight to about 125 parts by weight, for example, about 85 parts by weight to about 120 parts by weight, relative to 100 parts by weight of the aromatic isocyanate component.

In one embodiment, the aromatic isocyanate component may include 4,4'-diphenylmethanediisocyanate, and the polyol component may include 1,4-butanediol and polytetramethylene ether glycol (PTMG).

For example, the thermoplastic resin may include a reaction product of a composition including about 10 parts by weight to about 30 parts by weight, for example, about 10 parts by weight to about 25 parts by weight, for example, about 12 parts by weight to about 20 parts by weight, of 1,4-butanediol relative to 100 parts by weight of the 4,4'-diphenylmethanediisocyanate.

For example, the thermoplastic resin may include a reaction product of a composition including about 70 parts by weight to about 120 parts by weight, for example, more than about 70 parts by weight and less than about 120 parts by weight, of polytetramethylene ether glycol (PTMG) relative to 100 parts by weight of the 4,4'-diphenylmethanediisocyanate.

As described above, in the polishing layer (10), the ratio of the Shore D hardness of the polishing variable layer (101) and the polishing constant layer (102) may be from about 0.50 to about 1.50. FIG. 1 illustrates, by way of example, a case in which the separable interface (13) between the first surface (11) and the second surface (13) is one. Referring to this, the ratio of the Shore D hardness of the two adjacent layers (101, 102), that is, the polishing variable layer (101) and the polishing constant layer (102), with respect to the separable interface (13) as the standard may be from 0.50 to about 1.50. The ratio of the above Shore D hardness may be, for example, about 0.50 to about 1.50, for example, about 0.60 to about 1.50, for example, about 0.70 to about 1.40, for example, about 0.80 to about 1.20. When the above polishing variable layer (101) and the above polishing constant layer (102) each satisfy the above-described material and satisfy the hardness relative ratio, appropriate elasticity and strength can be transmitted to the polishing target through the first surface (11), and it can be more advantageous in implementing the desired polishing performance.

FIG. 3 schematically illustrates a cross-section of the polishing pad (110) according to one embodiment. Referring to FIG. 3, the polishing pad (110) may further include a cushion layer (20) on one surface of the polishing layer (10). At this time, the second surface (12) of the polishing layer (10) may function as an attachment surface for the cushion layer (20).

The cushion layer (20) is a layer that provides shock absorption to the polishing pad (110), and its Asker C hardness may be about 65 to about 75, for example, about 70 to about 75. In one embodiment, the ratio (Hc/Hp) of the Asker C hardness (Hc) of the cushion layer (20) to the Shore D hardness (Hp) of the polishing layer (10) may be about 1.00 to about 1.55, for example, about 1.25 to about 1.55, for example, about 1.27 to about 1.55.

Considering the manufacturing method of the semiconductor device described below, the polishing process is performed by directly or indirectly contacting the first surface (11), which is the polishing surface of the polishing layer (10), with the polishing target surface of the semiconductor substrate. At this time, a predetermined pressurizing condition may be applied depending on the polishing purpose. The cushion layer (20) provides appropriate elasticity with respect to the thickness direction of the polishing pad (110), thereby minimizing the occurrence of defects such as scratches on the polishing surface during the polishing process performed under such pressurizing conditions, and can contribute to significantly improving the polishing flatness of the polishing surface. When the ratio of the Shore D hardness of the polishing layer (10) and the Asker C hardness of the cushion layer (20) satisfies the above-mentioned range, such technical effects can be maximized.

The above cushion layer (20) may include non-woven fabric or suede, but is not limited thereto.

In one embodiment, the cushion layer (20) may include a nonwoven fabric. The term 'nonwoven fabric' refers to a three-dimensional network structure of nonwoven fibers. Specifically, the cushion layer (20) may include a nonwoven fabric and a resin impregnated into the nonwoven fabric.

The above nonwoven fabric may be a nonwoven fabric of fibers including, for example, one selected from the group consisting of polyester fibers, polyamide fibers, polypropylene fibers, polyethylene fibers, and combinations thereof.

The resin impregnated in the above nonwoven fabric may include, for example, one selected from the group consisting of polyurethane resin, polybutadiene resin, styrene-butadiene copolymer resin, styrene-butadiene-styrene copolymer resin, acrylonitrile-butadiene copolymer resin, styrene-ethylene-butadiene-styrene copolymer resin, silicone rubber resin, polyester elastomer resin, polyamide elastomer resin, and combinations thereof.

In one embodiment, the cushion layer (20) may include a nonwoven fabric of fibers including polyester fibers impregnated with a resin including a polyurethane resin.

In one embodiment, the cushion layer (20) may have a thickness of about 0.5 mm to about 2.5 mm, for example, about 0.8 mm to about 2.5 mm, for example, about 1.0 mm to about 2.5 mm, for example, about 1.0 mm to about 2.0 mm, for example, about 1.0 mm to about 1.8 mm.

Referring to FIG. 3, the polishing pad (110) according to one embodiment may further include a first adhesive layer (30) for attaching the polishing layer (10) and the cushion layer (20). The first adhesive layer (30) may include, for example, a heat sealing adhesive. Specifically, the first adhesive layer (30) may include one selected from the group consisting of a urethane adhesive, a silicone adhesive, an acrylic adhesive, and a combination thereof, but is not limited thereto.

Referring to FIG. 3, the polishing pad (110) may further include a second adhesive layer (40) for attachment to a platen. The second adhesive layer (40) may be an intermediary layer for attaching the polishing pad (110) and the platen of the polishing device, and may be derived from, for example, a pressure sensitive adhesive (PSA), but is not limited thereto.

The above polishing pad (110) may have a Shore D hardness of a polishing surface of about 45 to about 70 for the entire laminate, for example, about 45 to about 65, for example, more than about 45 and less than or equal to about 65, for example, about 50 to about 60. The combination of each layer constituting the above polishing pad (110) comprehensively implements a hardness within the above range, thereby minimizing the occurrence of defects such as scratches on the surface to be polished and improving the polishing flatness of the surface to be polished.

The ratio (Ht/Hp) of the Shore D hardness (Ht) of the entire laminate of the polishing pad (110) to the Shore D hardness (Hp) of the polishing layer (10) may be about 0.95 to about 1.10, for example, about 0.96 to about 1.10, for example, about 0.98 to about 1.10. The polishing layer (10) is a layer that directly affects the polishing performance among the entire configuration of the polishing pad (110), and when the Shore D hardness of the polishing layer (10) itself and the Shore D hardness implemented by the entire polishing pad (110) have the aforementioned relative ratio, it may be more advantageous in implementing the desired polishing performance.

In one embodiment, the compressibility of the polishing pad (110) may be from about 0.4% to about 2.0%, for example, from about 0.6% to about 1.6%, for example, from about 0.8% to about 1.5%, for example, from about 1.0% to about 1.5%. As described above, the polishing pad (110) can implement the compressibility in the above range through the segmented structural design in the thickness direction, and can obtain the advantage of maximizing the defect prevention performance by transmitting the corresponding elastic force to the polishing surface through the first surface (11).

Hereinafter, a method for manufacturing the above polishing pad (110) will be described.

The polishing pad (110) comprises a step of manufacturing a polishing layer (10) including a first surface (11) which is a polishing surface; a second surface (12) which is a reverse surface of the first surface (11); and at least one separable interface (13) between the first surface (11) and the second surface (12), and the step of manufacturing the polishing layer (10) comprises a step of manufacturing at least one polishing variable layer (101) which is a region from the first surface (11) to the separable interface (13); a step of manufacturing at least one polishing constant layer (102) which is a region from the separable interface (13) to the second surface (12); And the polishing variable layer (101) and the polishing constant layer (102) are laminated with the separable interface (13) as the lamination interface, and the polishing variable layer (101) and the polishing constant layer (102) can be manufactured through a manufacturing method in which the mutual Shore D hardness ratio of the polishing variable layer (101) and the polishing constant layer (102) is about 0.50 to about 1.50.

The details of each of the above polishing variable layer (101), the above polishing constant layer (102), and the above separable interface (103) are all the same as those described above with respect to the above polishing pad (110).

The step of laminating the above polishing variable layer (101) and the above polishing constant layer (102) may be a step of laminating with a double-sided adhesive. The double-sided adhesive is not particularly limited as long as it can adhere to each other, but may include, for example, one selected from the group consisting of a urethane adhesive, a silicone adhesive, an acrylic adhesive, and a combination thereof. As a result, the lamination interface of the above polishing variable layer (101) and the above polishing constant layer (102) can function as the separable interface (13).

The step of manufacturing the above polishing variable layer (101) may include a step of manufacturing a first composition including a urethane-based prepolymer; a step of manufacturing a second composition including the first composition, a foaming agent, and a curing agent; and a step of curing the second composition.

The matters relating to the above urethane-based prepolymer are the same as those described above with respect to the polishing pad (110), and the first composition is a composition corresponding to the preliminary composition among the matters described above with respect to the polishing pad (110), and the matters relating thereto are also all the same as those described above.

The viscosity of the first composition may be from about 100 cps to about 1,000 cps at about 80° C., for example, from about 200 cps to about 800 cps, for example, from about 200 cps to about 600 cps, for example, from about 200 cps to about 550 cps, for example, from about 300 cps to about 500 cps. By satisfying this viscosity range, the efficiency of the manufacturing process of the polishing variable layer (101) is improved, the dispersibility of other components is increased, and as a result, the polishing variable layer (101) may be advantageous in securing appropriate hardness and density.

All matters relating to the above-mentioned foaming agent and the above-mentioned hardening agent are the same as those described above with respect to the above-mentioned polishing pad (110).

When the foaming agent includes a solid foaming agent, the step of preparing the second composition may include a step of mixing the first composition and the solid foaming agent to prepare a 1-1 composition; and a step of mixing the 1-1 composition and the curing agent to prepare a second composition.

The viscosity of the above-mentioned 1-1 composition may be from about 1,000 cps to about 2,000 cps at about 80°C, for example, from about 1,000 cps to about 1,800 cps, for example, from about 1,000 cps to about 1,600 cps, for example, from about 1,000 cps to about 1,500 cps. When the viscosity of the above-mentioned 1-1 composition satisfies this range, it may be advantageous in an aspect similar to the technical significance of the viscosity of the above-mentioned first composition.

When the foaming agent includes a gaseous foaming agent, the step of preparing the second composition may include a step of mixing the first composition and the curing agent to prepare a first-second composition; and a step of injecting the gaseous foaming agent into the first-second composition to prepare the second composition.

In one embodiment, the first-second composition may further comprise a solid foaming agent.

For example, the injection rate of the gaseous foaming agent can be from about 0.8 L/min to about 2.0 L/min, for example, from about 0.8 L/min to about 1.8 L/min, for example, from about 0.8 L/min to about 1.7 L/min, for example, from about 1.0 L/min to about 2.0 L/min, for example, from about 1.0 L/min to about 1.8 L/min, for example, from about 1.0 L/min to about 1.7 L/min.

In one embodiment, the step of curing the second composition may include: preparing a mold preheated to a first temperature; injecting the second composition into the preheated mold to cure it; and post-curing the cured second composition under a second temperature condition higher than the first temperature.

In one embodiment, the temperature difference (T2-T1) between the first temperature (T1) and the second temperature (T2) can be from about 10°C to about 40°C, for example, from about 10°C to about 35°C, for example, from about 15°C to about 35°C.

In one embodiment, the first temperature can be from about 60° C. to about 100° C., for example, from about 65° C. to about 95° C., for example, from about 70° C. to about 90° C. In one embodiment, the second temperature can be from about 100° C. to about 130° C., for example, from about 100° C. to about 125° C., for example, from about 100° C. to about 120° C.

When applying multi-stage temperature conditions as described above in curing the second composition, the polishing variable layer (101) manufactured through this can be more advantageous in securing the physical/mechanical properties such as the desired hardness, tensile strength, and elongation.

In the step of curing the second composition, the step of injecting the second composition into the preheated mold and curing it can be performed for about 5 minutes to about 60 minutes, for example, for about 5 minutes to about 40 minutes, for example, for about 5 minutes to about 30 minutes, for example, for about 5 minutes to about 25 minutes.

The step of post-curing the cured second composition under a second temperature condition higher than the first temperature may be performed for about 5 hours to about 30 hours, for example, about 5 hours to about 25 hours, for example, about 10 hours to about 30 hours, for example, about 10 hours to about 25 hours, for example, about 12 hours to about 24 hours, for example, about 15 hours to about 24 hours.

The method for manufacturing the above polishing pad (110) may further include a step of processing the first surface (11).

The step of processing the first surface (11) may include at least one of the steps of: a step (1) of forming a groove on the first surface (11); a step (2) of line turning the first surface (11); and a step (3) of roughening the first surface (11).

In the above step (1), the groove may include at least one of a concentric groove formed at a predetermined interval from the center of the polishing variable layer (101) on the first surface (11) to the edge; and a radial groove formed continuously from the center of the polishing variable layer (101) on the first surface (11) to the edge.

In the above step (2), the line turning can be performed by using a cutting tool to cut the first surface (11) to a predetermined thickness.

In the above step (3), the roughening can be performed by processing the first surface (11) with a sanding roller.

The step of manufacturing the above polishing invariant layer (102) may include a step of preparing a thermoplastic resin raw material; and a step of processing the thermoplastic resin raw material.

The thermoplastic resin raw material may include one selected from the group consisting of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), thermoplastic polyurethane (TPU), and combinations thereof.

In one embodiment, the thermoplastic resin raw material may include a composition for producing thermoplastic polyurethane (TPU). The composition for producing TPU is not particularly limited, but may include, for example, an aromatic isocyanate component and a polyol component.

The above aromatic isocyanate component may include, for example, one selected from the group consisting of 2,4-toluenediisocyanate (2,4-TDI), 2,6-toluenediisocyanate (2,6-TDI), naphthalene-1,5-diisocyanate, p-phenylenediisocyanate, tolidinediisocyanate, 4,4'-diphenylmethanediisocyanate, and combinations thereof.

The above polyol compound may include, for example, one selected from the group consisting of polyether polyol, polyester polyol, polycarbonate polyol, acrylic polyol, and combinations thereof.

The polyol component of the thermoplastic resin raw material may not include an alcohol compound having three or more hydroxyl groups (-OH) per molecule. In another aspect, the polyol component of the thermoplastic resin raw material may be composed of a glycol having two hydroxyl groups (-OH) per molecule; or a diol compound.

The polyol component among the thermoplastic resin raw materials may have a weight average molecular weight (Mw) of about 80 g/mol to about 1000 g/mol, for example, about 90 g/mol to about 800 g/mol.

The above polyol compound may include, for example, one selected from the group consisting of polytetramethylene ether glycol (PTMG), polypropylene ether glycol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, diethylene glycol (DEG), dipropylene glycol (DPG), tripropylene glycol, polypropylene glycol, and combinations thereof.

In one embodiment, the thermoplastic resin raw material may contain the polyol component in a total amount of about 80 parts by weight to about 130 parts by weight, for example, about 80 parts by weight to about 80 parts by weight to about 125 parts by weight, for example, about 85 parts by weight to about 120 parts by weight, relative to 100 parts by weight of the aromatic isocyanate component.

In one embodiment, the aromatic isocyanate component may include 4,4'-diphenylmethanediisocyanate, and the polyol component may include 1,4-butanediol and polytetramethylene ether glycol (PTMG).

For example, the thermoplastic resin raw material may contain about 10 parts by weight to about 30 parts by weight of the 1,4-butanediol, for example, about 10 parts by weight to about 25 parts by weight, for example, about 12 parts by weight to about 20 parts by weight, relative to 100 parts by weight of the 4,4'-diphenylmethanediisocyanate.

For example, the thermoplastic resin raw material may contain about 70 parts by weight to about 100 parts by weight of the polytetramethylene ether glycol (PTMG) relative to 100 parts by weight of the 4,4'-diphenylmethanediisocyanate.

In one embodiment, the step of processing the thermoplastic resin raw material may include: a step of injecting the thermoplastic resin raw material into a mold preheated to about 70° C. to about 90° C., and curing for about 80 minutes to about 160 minutes; a step of post-curing the cured thermoplastic resin raw material at room temperature of about 20° C. to about 40° C.; and a step of aging the post-cured thermoplastic resin raw material at about 100° C. to about 120° C. for about 10 hours to about 15 hours.

The preheating temperature of the mold may be, for example, about 70° C. to about 90° C., for example, about 75° C. to about 85° C., and the curing time may be, for example, about 80 minutes to about 160 minutes, for example, about 100 minutes to about 150 minutes, for example, about 100 minutes to about 130 minutes, for example, about 110 minutes to about 130 minutes.

In the step of maturing the thermoplastic resin raw material, the temperature may be about 100° C. to about 120° C., for example, about 105° C. to about 115° C., and the time may be about 10 hours to about 15 hours, for example, about 10 hours to about 14 hours, for example, about 10 hours to about 13 hours, for example, about 11 hours to about 13 hours.

As described above, by applying a laminate of the polishing variable layer (101) and the polishing constant layer (102) to the polishing layer (10), it is possible to secure the advantage of being able to design precise and diverse physical properties in the thickness direction of the polishing layer (10), and to provide excellent polishing performance to the polishing surface of the polishing target through the first surface (11) of the polishing variable layer (101).

The method for manufacturing the above polishing pad (110) may further include a step of laminating a cushion layer (20) on the second surface (12) of the above polishing layer (10). Details regarding the cushion layer (20) are the same as those described above regarding the above polishing pad (110).

In one embodiment, the step of laminating the cushion layer (20) may include: a step of applying a heat-melting adhesive on the second surface (12); a step of applying a heat-melting adhesive on one surface of the cushion layer (20); and a step of laminating the second surface (12) and the cushion layer (20) such that the surfaces on which each heat-melting adhesive is applied are in contact with each other; and a step of fusing under pressurized or heated conditions.

The above heat-melting adhesive is not particularly limited, but may include, for example, one selected from the group consisting of a urethane adhesive, a silicone adhesive, an acrylic adhesive, and a combination thereof.

Referring to FIG. 3, during the lamination process of the cushion layer (20), a first adhesive layer (30) can be formed on the second surface (12).

In one embodiment, the method for manufacturing the polishing pad (110) may further include a step of forming a second adhesive layer (40) on one surface of the cushion layer (20). The second adhesive layer (40) is a component for attaching the polishing pad (110) to a surface of a polishing device, and may be derived from, for example, a pressure sensitive adhesive (PSA), but is not limited thereto.

Specifically, in one embodiment, the step of forming the second adhesive layer (40) may include the step of applying a pressure-sensitive adhesive to the surface opposite to the second surface (12) of the cushion layer (20) to which the cushion layer is attached; and the step of drying the pressure-sensitive adhesive.

In another embodiment, the step of forming the second adhesive layer (40) may include the step of preparing an adhesive film including a pressure-sensitive adhesive; and the step of bonding the adhesive film to the surface opposite to the second surface (12) of the cushion layer (20).

In another embodiment of the present invention, a method for manufacturing a semiconductor device is provided, comprising: providing a polishing pad including a polishing layer having a polishing surface on a platen; arranging a surface to be polished of a target object to be polished so that the polishing surface is in contact with the polishing surface, and then polishing the target object while relatively rotating the polishing pad and the target object under a pressurized condition; wherein the polishing layer includes a polishing variable layer including the polishing surface, and a polishing constant layer arranged on a back side of the polishing surface of the polishing variable layer, and a ratio of shore D hardnesses of the polishing variable layer and the polishing constant layer is 0.50 to 1.50.

All matters relating to the above polishing pad (110) are as described above. That is, all matters relating to the polishing layer (10) and the first surface (11), the second surface (12) and the separable interface (13) of the above polishing pad (110) are as described above with respect to the above polishing pad (110). When the above polishing pad (110) is applied to the method for manufacturing the semiconductor device, a semiconductor device of excellent quality can be produced under optimal material property conditions implemented by the structural and compositional characteristics of the above polishing pad (110) as described above.

Specifically, the ratio of the Shore D hardness of two adjacent layers based on the separable interface may be from about 0.50 to about 1.50, for example, from about 0.60 to about 1.50, for example, from about 0.70 to about 1.40, for example, from about 0.80 to about 1.20. In this way, through the detailed design in the thickness direction of the polishing pad, the method for manufacturing a semiconductor device using the same can secure excellent polishing results in terms of polishing flatness and defect prevention.

FIG. 4 is a schematic diagram illustrating a method for manufacturing the semiconductor device according to one embodiment. Referring to FIG. 4, the polishing pad (110) may be provided on the platen (120). When the polishing pad (110) is provided on the platen (120), the first surface (11) of the polishing layer (10) may be provided so that it becomes the uppermost surface, and the second surface (12) faces the platen (120).

In one embodiment, the polishing pad (110) and the platen (120) may be attached via an adhesive layer. For example, the adhesive layer may be derived from a pressure sensitive adhesive (PSA), but is not limited thereto.

The method for manufacturing the semiconductor device includes a step of arranging the polishing surface of the polishing target (130) so that it is in contact with the first surface (11), and then polishing the polishing target (130) while rotating the polishing pad (110) and the polishing target (130) relative to each other under a pressurized condition.

In one embodiment, the polishing target (130) may be a semiconductor substrate. For example, the polishing surface of the semiconductor substrate may include a metal oxide film, a metal nitride film, or a metal film. In one embodiment, the polishing surface may be a single film made of one of a metal oxide, a metal nitride, and a metal. In another embodiment, the polishing surface may be a composite film including at least two or more of a metal oxide, a metal nitride, and a metal.

In each of the metal oxide film, the metal nitride film, and the metal film, the metal component may include one selected from the group consisting of silicon (Si), copper (Cu), tantalum (Ta), titanium (Ti), molybdenum (Mo), and combinations thereof.

In one embodiment, the polishing surface of the polishing target (130) may be a single film made of a silicon oxide film. In another embodiment, the polishing surface of the polishing target (130) may be a single film made of a copper film. In another embodiment, the polishing surface of the polishing target (130) may be a composite film including a silicon oxide film. In another embodiment, the polishing surface of the polishing target (130) may be a composite film including a copper film.

The load applied to the polishing surface of the polishing target (130) against the first surface (11) may be appropriately designed depending on the type and purpose of the polishing surface, and may be, for example, from about 0.01 psi to about 20 psi, and for example, from about 0.1 psi to about 15 psi. As described above, the polishing pad (110) has structural features segmented in the thickness direction, and through these structural features, it may provide appropriate rigidity and elasticity suitable for various purposes to the polishing surface under the pressurizing conditions in the above range. As a result, when the polishing target (130) includes a semiconductor substrate, the final polishing result of the semiconductor substrate may be significantly improved in terms of polishing flatness and defect prevention.

The polishing pad (110) and the polishing target (130) can rotate relative to each other while their respective polishing surfaces (11) and to-be-polished surfaces are in contact with each other. At this time, the rotation direction of the polishing target (130) and the rotation direction of the polishing pad (110) may be the same direction or opposite directions. The polishing surface (11) and the to-be-polished surface of the polishing target (130) may be in direct contact, or may be indirectly in contact via a component included in a fluid slurry or the like. The rotation speeds of the polishing target (130) and the polishing pad (110) may be selected from a range of about 10 rpm to about 500 rpm depending on the purpose, and for example, may be about 30 rpm to about 200 rpm, but are not limited thereto. As described above, the polishing pad (110) can provide polishing performance suitable for various purposes through structural features segmented in the thickness direction. When the above polishing target (130) and the polishing pad (110) are in contact with each other and rotate at a rotation speed within the above range, the behavior due to centrifugal force and frictional force is mutually linked with the structural characteristics of the polishing pad (110), and thus excellent polishing results can be produced in terms of polishing flatness and defect prevention for the polishing surface.

Referring to FIG. 1, the polishing layer (10) may include at least one polishing variable layer (101) in a region from the polishing surface (11) to the separable interface (13); and at least one polishing constant layer (102) in a region from the separable interface (13) to the second surface (12). All matters relating to the polishing variable layer (101) and the polishing constant layer (102) are the same as those described above with respect to the polishing pad (110) and its manufacturing method.

In the method for manufacturing the semiconductor device, the polishing variable layer (101) may have a first polishing variability index of about 0.1 to 11.0 according to the above formula 1, for example, about 0.1 to about 9.0, for example, about 0.2 to about 9.0, for example, about 0.2 to about 8.5, for example, about 0.2 to about 8.0, for example, about 0.2 to about 7.5, for example, about 0.5 to about 7.5, for example, about 0.8 to about 7.5, for example, about 0.9 to about 7.5, for example, about 1.0 to about 6.0, for example, about 1.8 to 3.5, for example, about 1.8 to 2.5.

The above polishing variable layer (101) is a region where physical characteristics and/or chemical characteristics change during a polishing process of a semiconductor device manufacturing method using the polishing pad (110), and has a predetermined lifespan in terms of providing a target level of polishing performance. The introduction point of the lifespan of the polishing variable layer (101) means any point in time between the region itself; or before the polishing pad (110) is manufactured and applied to the process. In addition, the end point of the lifespan of the polishing variable layer (101) means a point in time when the polishing variable layer (101) no longer implements polishing performance, requiring replacement of the region itself; or the entire polishing pad (110).

The first polishing variability index by the above formula 1, which uses the surface roughness (Ri, Rf) at the introduction point of the life cycle and the end point of the life cycle of the above polishing variable layer (101) as factors and the total thickness (Ti, Tf) of the above polishing pad (110), is an indicator representing the variability performance of the above polishing variable layer (101), and by having a variability corresponding to the value of the above formula 1 being in the above-mentioned range, that is, from about 0.1 to about 11.0, the polishing variable layer (101) can have structural characteristics optimized for polishing efficiency as a part of the above polishing layer (10), and at the same time, can implement constant polishing performance throughout its life cycle, which can be more advantageous in mass production of semiconductor devices of the same quality.

The above Ti may have a thickness of, for example, about 800 μm to about 5000 μm, for example, about 1000 μm to about 4000 μm, for example, about 1000 μm to about 3000 μm, for example, about 1500 μm to about 3000 μm, for example, about 1700 μm to about 2700 μm, for example, about 2000 μm to about 3500 μm, but is not limited thereto.

The above Ri may be, for example, about 5 μm to about 15 μm, for example, about 5 μm to about 12 μm, for example, about 5 μm to about 10 μm, but is not limited thereto.

In one embodiment, when the Ti and Ri each satisfy the above-described ranges, and at the same time the first polishing variability index satisfies the above-described ranges, it may be more advantageous in terms of the structural characteristics of the polishing variable layer (101) and the implementation of polishing performance.

In one embodiment, the polishing pad (110) may include at least one groove (Groove, 14) having a depth (d1) smaller than or equal to the total thickness (D1) of the polishing variable layer (101) on the polishing surface (11). The groove (14) may control the fluidity of the polishing liquid or polishing slurry supplied onto the polishing surface (11) during a polishing process using the polishing pad (110), or may control the size of the area where the polishing surface (11) and the target polishing surface of the polishing object come into direct contact, thereby appropriately implementing physical polishing characteristics.

For example, the polishing pad (110) may include a plurality of grooves (14) on the polishing surface (11). In one embodiment, the planar shape of the polishing pad (110) may be substantially circular, and the plurality of grooves (14) may have a concentric structure spaced apart from a predetermined interval from the planar center of the polishing pad (110) toward the end. In another embodiment, the plurality of grooves (14) may have a radial structure continuously formed from the planar center of the polishing pad (110) toward the end. In yet another embodiment, the plurality of grooves (14) may include both concentric grooves and radial grooves.

In the polishing variable layer (101) which is a region from the polishing surface (11) to the separable interface (13), the polishing surface (11) may include at least one groove (14). At this time, in the method for manufacturing the semiconductor device, the second polishing variability index of the polishing variable layer (101) by the above formula 2 may be about 0.1 to about 3.5, for example, about 0.1 to about 3.3, for example, about 0.1 to about 3.0, for example, about 0.1 to about 2.0, for example, about 0.3 to about 1.8, for example, about 0.5 to about 1.5, for example, about 0.5 to about 1.2, for example, about 0.5 to 1.0, for example, about 0.6 to about 1.0.

The description of the introduction point of the life and the end point of the life of the above polishing variable layer (101) is as described above with respect to the first polishing variability index by the above formula 1. When the second polishing variability index of the above polishing variable layer (101) satisfies the above-mentioned range, the polishing variable layer (101) can provide a structure optimized in terms of the fluidity of the polishing liquid or polishing slurry, and the direct contact area provided to the surface to be polished is secured at an appropriate level, which can be more advantageous in securing a polishing rate in the target range.

The above Gi may be, for example, about 600 μm to about 900 μm, for example, about 650 μm to about 900 μm, for example, about 700 μm to about 900 μm, but is not limited thereto.

In one embodiment, when the Ri and Gi each satisfy the above-described ranges, and at the same time the second polishing variability index satisfies the above-described ranges, it may be more advantageous in terms of implementing polishing performance by the structural features of the polishing variability layer (101).

When the polishing surface (11) includes at least one groove (14) having a depth smaller than or equal to the total thickness of the polishing variable layer (101), the depth change rate (%) of the groove (14) according to Equation 3 in the polishing variable layer (101) may be about 20% to about 80%, for example, about 30% to about 80%, for example, about 40% to about 80%, for example, about 45% to about 75%, for example, about 50% to about 70%.

Referring to FIG. 1, the depth (d1) of the groove (14) changes during the polishing process from the depth (Gi) at the time of introduction of the life to the depth (Gf) at the time of termination of the life. Specifically, the depth (d1) of the groove (14) gradually becomes shallower as the polishing surface (11) is worn away as the polishing surface (11) and the polishing target surface are polished through physical contact with each other. At this time, the value of the equation 3, which has as elements the depth (Gi) of the groove at the time of introduction of the life and the depth (Gf) of the groove at the time of termination of the life, can satisfy the aforementioned range only when the physical characteristics of the polishing variable layer (101), such as elongation, tensile strength, and hardness, are appropriately supported. Specifically, if the physical properties of the polishing variable layer (101) are not properly supported, the shallower the groove depth (d1) becomes, the greater the influence of changes in the fluidity of the polishing slurry, etc., on the polishing performance, which may rapidly deteriorate the overall polishing performance. The polishing variable layer (101) according to one embodiment can exhibit optimal physical properties corresponding thereto by satisfying the above-described range of the value of the above-described Equation 3, and based on this, even if the groove depth (d1) becomes shallow, the influence thereof on the polishing performance can be minimized, thereby implementing excellent polishing performance throughout the entire polishing process according to the method for manufacturing the semiconductor device.

When the polishing pad (110) includes at least one groove on the polishing surface (11), the width (w1) of the groove (14) may be from about 0.2 mm to about 1.0 mm, for example, from about 0.3 mm to about 0.8 mm, for example, from about 0.4 mm to about 0.7 mm. When the width of the groove (14) satisfies the above range, the size of the contact area between the polishing surface of the polishing target (130) and the polishing surface (11) may be appropriately secured, and the fluidity of the polishing liquid or polishing slurry applied to the polishing surface (11) may be appropriately secured, so that excellent final polishing performance may be implemented.

When the polishing pad (110) includes a plurality of grooves (14) on the polishing surface (11), the pitch (pitch, p1) of the grooves (14), which is defined as the spacing between two adjacent grooves (14), may be appropriately designed in the same context as the width (w1) of the grooves (14) to contribute to the implementation of polishing performance required in the method for manufacturing the semiconductor device. For example, the pitch (p1) of the grooves (14) may be about 1.5 mm to about 5.0 mm, for example, about 1.5 mm to about 4.0 mm, for example, about 1.5 mm to about 3.0 mm.

Referring to FIG. 4, in one embodiment, the method for manufacturing the semiconductor device may further include a step of supplying polishing slurry (150) onto the polishing surface (11) of the polishing pad (110). For example, the polishing slurry (150) may be supplied onto the polishing surface (11) through a supply nozzle (140).

The flow rate of the polishing slurry (150) sprayed through the supply nozzle (140) may be from about 10 ml/min to about 1,000 ml/min, for example, from about 10 ml/min to about 800 ml/min, for example, from about 50 ml/min to about 500 ml/min, but is not limited thereto.

The above polishing slurry (150) may include, but is not limited to, silica slurry or ceria slurry.

Referring to FIG. 4, the polishing target (130) can be polished while being pressed with a predetermined load to the polishing surface (11) while mounted on a polishing head (160). The polishing target (130) can be mounted so that its polished surface faces the polishing surface (11) when mounted on the polishing head (160). The load with which the polishing surface of the polishing target (130) is pressed against the polishing surface (11) can be appropriately designed depending on the type and purpose of the polishing surface, but can be, for example, about 0.01 psi to about 20 psi, for example, about 0.1 psi to about 15 psi, for example, about 1 psi to about 12 psi, for example, about 3 psi to about 6 psi.

In one embodiment, the method for manufacturing the semiconductor device may further include a step of processing the polishing surface (11) of the polishing pad (110) using a conditioner (170) simultaneously with the polishing of the polishing target (130) in order to maintain the polishing surface (11) of the polishing pad (110) in a state suitable for polishing.

The above conditioner (170) can perform the function of roughening the polishing surface (11) while rotating at a predetermined rotation speed. The rotation speed of the conditioner (170) can be, for example, about 50 rpm to about 150 rpm, and for example, about 80 rpm to about 120 rpm. Through surface treatment by the rotation of the conditioner (170), the polishing surface (11) can maintain an optimal surface state throughout the entire polishing process, and the effect of extending the polishing life can be obtained.

The pressing pressure of the conditioner (170) on the polishing surface (11) may be, for example, about 1 lbf to about 12 lbf, for example, about 3 lbf to about 9 lbf. Through surface treatment performed by pressing the conditioner (170) under these conditions, the polishing surface (11) can maintain an optimal surface state throughout the polishing process, and the effect of extending the polishing life can be obtained.

Hereinafter, specific examples of the present invention will be presented. However, the examples described below are only intended to specifically illustrate or explain the present invention, and the scope of the rights of the present invention is not construed as being limited thereby, and the scope of the rights of the present invention is determined by the claims.

<Examples and Comparative Examples>

Example 1

An aromatic diisocyanate containing 25 parts by weight of 2,6-toluene diisocyanate (2,6-TDI) and 100 parts by weight of 2,4-toluene diisocyanate (2,4-TDI) was prepared, and 11 parts by weight of 4,4'-dicyclohexyl methane diisocyanate (H ₁₂ MDI) was mixed with respect to 100 parts by weight of the total aromatic diisocyanate to prepare an isocyanate component. 130 parts by weight of polytetramethylene ether glycol (PTMG) having a weight average molecular weight (Mw) of 1,000 g/mol was prepared with respect to 100 parts by weight of the total isocyanate component, and 14 parts by weight of diethylene glycol (DEG) having a weight average molecular weight (Mw) of 106 g/mol was mixed with respect to 100 parts by weight of the total isocyanate component to prepare a polyol component. A mixed raw material including the above isocyanate component and the above polyol component was placed in a four-necked flask and reacted at 80°C to prepare a preliminary composition including a urethane prepolymer. The content of isocyanate groups (NCO groups) in the preliminary composition was adjusted to 9 wt%. 4,4'-methylenebis(2-chloroaniline) (MOCA) as a curing agent was mixed into the preliminary composition such that the molar ratio of the NH ₂ groups of the MOCA to the NCO groups in the preliminary composition was 0.96. In addition, 1.0 part by weight of a solid blowing agent (Akzonobel), which is an expandable particle, and 1.0 part by weight of a silicone surfactant (OFX-193) were mixed into the preliminary composition. The above preliminary composition was injected into a mold that was 1,000 mm wide, 1,000 mm long, and 3 mm high and was preheated to 90°C, at a discharge rate of 10 kg/min, and simultaneously, nitrogen (N ₂ ) gas as a gaseous foaming agent was injected at an injection rate of 1.0 L/min for the same time as the injection time of the preliminary composition. Then, the preliminary composition was post-cured under a temperature condition of 110°C to produce a sheet. The sheet was line-turned, and concentric grooves having a width (w1) of 0.5 mm, a pitch (p1) of 3.0 mm, and a depth (d1) of 0.85 mm were processed on the surface to produce a polishing variable layer having a thickness of 1.0 mm.

Meanwhile, an aromatic isocyanate compound including 4,4'-diphenylmethanediisocyanate (MDI) was prepared, and 18 parts by weight of 1,4-butanediol and 71 parts by weight of polytetramethylene ether glycol (PTMG 650) were mixed relative to 100 parts by weight of the MDI, placed into a cake-shaped mold that was 1,000 mm wide, 1,000 mm long, and 3 mm high and preheated to 80°C, cured for 120 minutes, post-cured at room temperature, and then aged at 110°C for 12 hours and sliced to a thickness of 1.0 mm to prepare a polishing-resistant layer.

Meanwhile, a cushion layer having a structure in which a polyester resin nonwoven fabric is impregnated with a urethane resin and a thickness of 1.1 mm was prepared.

A double-sided adhesive tape was attached on the back surface of the grooved surface of the above polishing variable layer; on both sides of the above polishing constant layer; and on one side of the above cushion layer; and the above polishing variable layer, the above polishing constant layer, and the above cushion layer were sequentially laminated, and then the adhesive tape attachment surfaces were arranged to be in contact with each other, and then laminated to manufacture a polishing pad having a total thickness of 3.2 (±0.5) mm.

Example 2

An aromatic isocyanate compound containing 4,4'-diphenylmethanediisocyanate (MDI) was prepared, and 14 parts by weight of 1,4-butanediol and 100 parts by weight of polytetramethylene ether glycol (PTMG 650) were mixed with 100 parts by weight of the MDI, placed into a cake-shaped mold that was 1,000 mm wide, 1,000 mm long, and 3 mm high and preheated to 80°C, cured for 120 minutes, post-cured at room temperature, aged at 110°C for 12 hours, and sliced to a thickness of 1.0 mm to prepare a polishing-resistant layer.

Meanwhile, a cushion layer having a structure in which a polyester resin nonwoven fabric is impregnated with a urethane resin and a thickness of 1.1 mm was prepared.

A double-sided adhesive tape was attached on the back surface of the grooved surface of the above polishing variable layer; on both sides of the above polishing constant layer; and on one side of the above cushion layer; and the above polishing variable layer, the above polishing constant layer, and the above cushion layer were sequentially laminated, and then the adhesive tape attachment surfaces were arranged to be in contact with each other, and then laminated to manufacture a polishing pad having a total thickness of 3.2 (±0.5) mm.

Comparative Example 1

In the above Example 1, the polishing constant layer was excluded, the polishing variable layer was manufactured to a thickness of 2.0 mm, and a double-sided adhesive tape was attached on the back surface of the surface where the groove of the polishing variable layer was formed; and on one surface of the cushion layer; and then the respective adhesive tape attachment surfaces were arranged so that they were in contact with each other and then laminated to manufacture a polishing pad having a total thickness of 3.1 (±0.5) mm, with the exception that a polishing pad was manufactured in the same manner as in the above Example 1.

Comparative Example 2

In the above Example 1, a polishing pad having a total thickness of 2.1 (±0.5) mm was manufactured by the same method as in the above Example 1, except that a double-sided adhesive tape was attached to the back surface of the surface where the groove of the above polishing variable layer was formed, and one surface of the above cushion layer, and then the respective adhesive tape attachment surfaces were arranged so that they were in contact with each other and then laminated to manufacture a polishing pad.

Comparative Example 3

A polishing pad was manufactured in the same manner as in Example 1, except that an aromatic isocyanate compound including 4,4'-diphenylmethanediisocyanate (MDI) was prepared, 11 parts by weight of 1,4-butanediol and 120 parts by weight of polytetramethylene ether glycol (PTMG 650) were mixed with 100 parts by weight of the MDI, the mixture was placed into a cake-shaped mold that was 1,000 mm wide, 1,000 mm long, and 3 mm high and preheated to 80°C, cured for 120 minutes, post-cured at room temperature, aged at 110°C for 12 hours, and sliced to a thickness of 1.0 mm to prepare a polishing-invariant layer.

<Evaluation>

Experimental Example 1: Hardness Characteristics Evaluation

The Shore D hardness of the laminates each composed of the polishing variable layer, the polishing constant layer, the cushion layer and at least one of the combinations thereof for each of the above examples and comparative examples was measured. Specifically, samples were prepared by cutting the width and length into a size of 5 cm X 5 cm, and each sample was stored at 25°C for 12 hours and then measured using a hardness meter (Bareiss, HPEIII). In addition, based on each hardness measurement value, the ratio of the hardness (H1) of the polishing variable layer to the hardness (H2) of the polishing constant layer (H2/H1); the ratio of the hardness (Hp) of the polishing layer to the hardness (Hc) of the cushion layer (Hc/Hp); and the ratio of the hardness (Hp) of the polishing layer to the hardness (Ht) of the entire polishing pad (Hp/Ht) were calculated. The results are as shown in Table 1 below.

Experimental Example 2: Evaluation of Compression Properties

For each of the polishing pad samples of the above examples and comparative examples, 25 mm x 25 mm, the initial thickness (D1) in the unloaded state was measured, and the deformed thickness (D2) was measured by applying pressure under conditions of applying pressure to the sample with an 800 g weight for 3 minutes at room temperature. Then, the compression ratio (%) was derived using the equation (D1-D2)/D1Х100.

Experimental Example 3: Evaluation of Polishing Variability

For each of the above examples and comparative examples, the surface roughness (Ri) of the first surface of the polishing variable layer before each polishing pad was manufactured and applied to the polishing process was measured based on the centerline average roughness (Ra), and the total thickness (Ti) of each polishing pad and the depth (Gi) of the groove on each first surface were measured.

Next, for each polishing pad, a life time prediction evaluation was performed by simulating the actual polishing evaluation. The pads were aged using a dummy wafer with a silicon oxide film, calcined ceria slurry (KC Tech ACS-350), and a 4-inch conditioner, and the polishing rate change was measured by inserting a monitoring wafer at regular intervals. The polishing conditions were evaluated under a pressure condition of 4.0 psi on the polishing surface of the polishing head and a slurry inflow rate of 200 mm/L.

For each polishing pad, the point at which the polishing rate changed by 20% from the initial polishing rate was set as the end of the life of the polishing pad, and the surface roughness (Rf) of the first surface of the polishing variable layer of each dried polishing pad was measured based on the centerline average roughness (Ra), and the total thickness (Tf) of each polishing pad and the depth (Gf) of the groove on each first surface were measured. The results are shown in Table 1 below.

Experimental Example 4: Polishing Performance Evaluation

For each of the polishing pads of the above examples and comparative examples, polishing was performed in the same manner as in Experimental Example 3, and then each polishing performance was evaluated as follows. The results are as shown in Table 1.

(1) Average polishing rate

Polishing was performed in the same manner as in Experimental Example 3 above, but after polishing for 1 minute, the film thickness change before and after polishing was measured using an optical interference thickness measuring device (SI-F80R, Kyence) on the dried silicon wafer. Thereafter, the polishing rate was calculated using the following formula. In this way, the polishing rate was measured a total of 5 times, and the number average value was obtained and used as the average polishing rate.

Polishing rate (Å/min) = Polishing thickness of silicon wafer (Å) / Polishing time (min)

(2) Defect

Polishing was performed using the same method as in Experimental Example 3 above, but after polishing for 1 minute, the polished surface of the polishing target was visually observed to derive the number of defects such as scratches. Specifically, after polishing, the silicon wafer was moved to a cleaner and cleaned for 10 seconds each using 1% hydrogen fluoride (HF) and purified water (DIW); 1% _nitric acid ( _H2NO3 ) and purified water (DIW). Afterwards, it was moved to a spin dryer, cleaned with purified water (DIW), and then dried with nitrogen ( _N2 ) for 15 seconds. The dried silicon wafer was visually observed for changes in defects before and after polishing using a defect measuring device (Tenkor, XP+).

(3) Polishing flatness

Polishing was performed using the same method as in Experimental Example 3 above, but after polishing for 1 minute, the film thickness within the plane of 98 wafers was measured and the polishing flatness (WIWNU: Within Wafer Non Uniformity, %) was derived using the formula (standard deviation of polished thickness (Å) / average polished thickness (Å)) X 100.

Referring to Table 1 above, the polishing pads of Examples 1 and 2 were designed to have a laminated structure of the polishing variable layer and the polishing constant layer of different materials applied to the polishing layer, while satisfying a range of a hardness ratio between the two layers of about 0.50 to about 1.50, thereby realizing excellent polishing performance equivalent to or superior to that of Comparative Examples 1 to 3 in terms of polishing rate, defects, and polishing flatness. At this time, it was confirmed that the polishing pads of Examples 1 and 2 obtained improved effects in terms of productivity and economy in addition to the original polishing function by applying a thermoplastic resin raw material that is easy to recycle as a raw material for the polishing constant layer.

110: Polishing pad
10: Polishing layer
101: Polishing Variable Layer
102: Polishing constant layer
11: First side, polishing surface
12: Page 2
13: Separable interface
14: Groove
20: Cushion layer
30: 1st adhesive layer
40: Second adhesive layer
w1: width of groove
p1: pitch of the groove
d1: Depth of groove
D1: Thickness of the polishing variable layer
15: Qi Gong
120: The right answer
130: Semiconductor substrate
140: Nozzle
150: Polishing slurry
160: Carrier
170: Conditioner

Claims (12)

Contains a polishing layer,
The above polishing layer includes a polishing variable layer having a polishing surface; and a polishing constant layer disposed on the back side of the polishing surface of the polishing variable layer.
The ratio of the Shore D hardness of the above-mentioned polishing variable layer to the Shore D hardness of the above-mentioned polishing constant layer is 0.50 to 1.50,
The first polishing variability index of the above polishing variable layer according to the following formula 1 is 0.1 to 11.0.
Polishing pad:
[Formula 1]

In the above equation 1,
The above Ri is the surface roughness (Ra) of the polishing surface at the time of introduction of the life of the above polishing variable layer,
The above Rf is the surface roughness (Ra) of the polished surface at the end of the life of the above polishing variable layer,
The above Ti is the total thickness of the polishing pad at the time of introduction of the life of the above polishing variable layer,
The above Tf is the total thickness of the polishing pad at the end of the life of the polishing variable layer. In the first paragraph,
The above polishing variable layer is 30 to 60 volume% of the total volume of the polishing layer.
Polishing pad. delete In the first paragraph,
The above polishing variable layer includes at least one groove on the polishing surface having a depth less than the total thickness of the polishing variable layer or equal to the total thickness of the polishing variable layer,
The second polishing variability index of the above polishing variable layer according to the following formula 2 is 0.1 to 3.5.
Polishing pad:
[Formula 2]

In the above equation 2,
The above Ri is the surface roughness (Ra) of the polishing surface at the time of introduction of the life of the above polishing variable layer,
The above Rf is the surface roughness (Ra) of the polished surface at the end of the life of the above polishing variable layer,
The above Gi is the depth of the groove at the time of introduction of the life of the above polishing variable layer,
The above Gf is the depth of the groove at the end of the life of the above polishing variable layer. In the first paragraph,
The above polishing variable layer includes at least one groove on the polishing surface having a depth less than the total thickness of the polishing variable layer or equal to the total thickness of the polishing variable layer,
The depth change rate (%) of the groove according to the following formula 3 is 20% to 100%,
Polishing pad:
[Formula 3]

In the above equation 3,
The above Gi is the groove depth at the time of introduction of the life of the above polishing variable layer,
The above Gf is the groove depth at the end of the life of the above polishing variable layer. In the first paragraph,
Shore D hardness for the entire laminate is 45 to 70,
Polishing pad. In the first paragraph,
The ratio of the Shore D hardness of the entire polishing pad to the Shore D hardness of the polishing layer is 0.95 to 1.10.
Polishing pad. In the first paragraph,
The above polishing variable layer comprises a thermosetting resin,
The above polishing invariant layer comprises a thermoplastic resin,
Polishing pad. In the first paragraph,
The above polishing variable layer comprises a cured product of a preparatory composition comprising a urethane-based prepolymer.
Polishing pad. In the first paragraph,
The above polishing invariant layer comprises one selected from the group consisting of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), thermoplastic polyurethane (TPU), and combinations thereof.
Polishing pad. A step of providing a polishing pad including an abrasive layer having an abrasive surface on a surface;
A step of polishing the polishing target while relatively rotating the polishing pad and the polishing target under a pressurized condition after arranging the polishing target so that the polishing target's polishing surface is in contact with the polishing surface;
The above polishing layer includes a polishing variable layer including the polishing surface, and a polishing constant layer arranged on the back side of the polishing surface of the polishing variable layer,
The ratio of the shore D hardness of the above polishing variable layer and the above polishing constant layer is 0.50 to 1.50,
The first polishing variability index of the above polishing variable layer according to the following formula 1 is 0.1 to 11.0.
Method for manufacturing semiconductor devices:
[Formula 1]

In the above equation 1,
The above Ri is the surface roughness (Ra) of the polishing surface at the time of introduction of the life of the above polishing variable layer,
The above Rf is the surface roughness (Ra) of the polished surface at the end of the life of the above polishing variable layer,
The above Ti is the total thickness of the polishing pad at the time of introduction of the life of the above polishing variable layer,
The above Tf is the total thickness of the polishing pad at the end of the life of the polishing variable layer. In Article 11,
The load applied to the polishing surface of the polishing target is 0.01 psi to 20 psi.
A method for manufacturing a semiconductor device.