JP4612852B2 - Imprint master, imprint apparatus including the imprint master, and method for manufacturing the imprint master - Google Patents

Description

  The present invention relates to an imprint master, an imprint apparatus including the imprint master, and a method for manufacturing the imprint master.

  In recent years, there has been an increasing interest in microstructures that can be applied to functional materials and functional devices and methods for producing the same. One of the fine structure forming methods is a method using nanoimprinting described in Patent Document 1. In this nanoimprint method, an imprint master having a concavo-convex pattern of several tens to several hundreds of nanometers processed by electron beam lithography or the like is pressed against a transfer plate having a soft resist thin film surface on a flat substrate. This is a fine structure forming method in which a transfer target plate having the fine concavo-convex structure pattern transferred thereon is obtained by separating it.

In such an imprint method including the nanoimprint method, as the uneven pattern area increases or the imprint master preparation method diversifies, the strength of the imprint master and the entire surface of the imprint master are uniformly pressed. There has been a growing demand for the application of. For this reason, in order to increase the strength of the imprint master so far, for example, as in Patent Document 2, an imprint master having an uneven pattern and a reinforcing plate for reinforcing the imprint master are made of a single layer metal. What has been made to be reinforced by joining has been proposed.
In order to make the pressure uniform, for example, as in Patent Document 3, a technique has been proposed in which a buffer layer is provided between an imprinting master and a press surface.
US Pat. No. 5,772,905 JP 2000-82243 A JP 2003-157520 A

  In the imprint method including the nanoimprint method, as described above, the strength of the imprint master, or the uniformity of the applied pressure to the master surface, is an important issue. Although the thing of patent document 3 respond | corresponds to one of them, these are not necessarily sufficient to satisfy the said multifaceted request | requirement simultaneously. For example, even if the imprint master and the reinforcing plate that reinforces the imprint master are joined by a single layer metal as in the conventional example, the film thickness distribution of the imprint master and the accidental occurrence that occurs during imprinting It is insufficient to absorb the pressure distribution due to scratches or the like. In addition, even when a resin sheet or the like is used for the role of the buffer, a phenomenon such as an accidental deflection of the resin sheet and a decrease in applied pressure uniformity may occur.

  Furthermore, in the imprint method as described above, in addition to the above-described request, highly accurate temperature control in the imprint process is an important issue. For example, when a resist film such as PMMA is used as a pattern transfer film and an imprint master plate on which a fine pattern is formed is pressed, the transfer plate coated with the resist is heated to a temperature equal to or higher than the glass transition temperature of the resist, A process of cooling the imprint master and the transfer target plate to room temperature and peeling the imprint master from the transfer target plate is required. For this reason, high-precision temperature control in the imprint process is required for high-precision pattern transfer and high throughput. For example, if a resin sheet is used for the buffer layer, it is difficult to adjust the temperature of the imprint master due to low thermal conductivity, and it is necessary to replace the sheet every time imprinting is performed. This is necessary and hinders high throughput.

  In view of the above problems, the present invention provides an imprint master that increases the strength of the imprint master and improves the uniformity of the pressure applied to the master surface, an imprint apparatus including the imprint master, and the imprint It is an object of the present invention to provide a method for manufacturing a printing master.

In order to solve the above-described problems, the present invention provides an imprint master configured as follows, an imprint apparatus including the imprint master, and a method for manufacturing the imprint master.
That is, the imprint master of the present invention is an imprint master provided with a mold having an uneven pattern, a mold support substrate that supports the mold, and a metal bonding layer between the mold and the mold support substrate. The metal bonding layer includes a first layer configured to include a first metal material from the mold side and a second metal material having a melting point higher than that of the first metal material. It is characterized by having two layers.
The imprint apparatus of the present invention includes an imprint master and a pair of press surfaces, and applies pressure by sandwiching the imprint master and the transfer plate between the pair of press surfaces. In the imprint apparatus for transferring the concave / convex pattern of the master for printing onto the transfer target plate, the imprint master is constituted by the above-described master for imprint.
Further, the imprint apparatus of the present invention includes an imprint master, presses the imprint master and the transfer target plate between a pair of press surfaces, and applies an uneven pattern on the imprint master. In the imprint apparatus for transferring to a transfer target plate, one press surface of the pair of press surfaces is constituted by the mold support substrate of the above-described imprint master.
In addition, the method for manufacturing an imprint master according to the present invention includes a mold having a concavo-convex pattern and a first metal material interposed between the mold and one press surface of the pair of press surfaces. A method for manufacturing an imprint master comprising a first layer and a second layer composed of a second metal material having a melting point higher than that of the first metal material, wherein one of the pair of press surfaces is provided. Bonding the second layer to the press surface;
Between the second layer and the other press surface of the pair of press surfaces, the first layer and the mold, the first layer as the second layer side, and unevenness of the mold Installing the pattern area as the other press surface side;
The second low pressure material bonded to the one press surface by applying a pressure between the pair of press surfaces at a temperature closer to the melting point of the first metal material than the second metal material. Bonding the mold to the layer made of the melting point metal material through the layer made of the first low melting point metal material.
Further, in the method for producing an imprint master according to the present invention, a layer made of a first low-melting-point metal material interposed between a mold having a concavo-convex pattern and one press surface of the mold and a pair of press surfaces. And a method for manufacturing an imprinting master having a layer made of a second low-melting-point metal material having a higher melting point than the first low-melting-point metal material, wherein the first low-melting-point metal is interposed between a pair of press surfaces. A metal bonding layer having a structure in which a layer made of the second low-melting-point metal material is sandwiched between layers made of a metal material and the mold, the metal bonding layer being one press surface side of the pair of press surfaces, Installing the uneven pattern area as the other press surface side;
Applying a pressure between the pair of press surfaces at a temperature close to the melting point of the first low melting point metal material, and bonding the mold to the one press surface via the metal bonding layer; The structure which has these can be taken.

  ADVANTAGE OF THE INVENTION According to this invention, the intensity | strength of the master for imprint can be raised and the uniformity of the applied pressure with respect to a master surface can be improved.

The imprint master according to the embodiment of the present invention will be described below.
FIG. 1 shows the configuration of the first embodiment of the imprinting master according to the present embodiment.
In FIG. 1, 1 is a mold having an uneven pattern, 2 is a first low-melting-point metal material (first layer), and 3 is a second low-melting-point metal material (second layer). The low melting point metal material here refers to a material having a melting point of about 300 ° C. or less. In the present invention, the expression “metal material” includes not only the metal material itself but also an alloy material. Hereinafter, the first low-melting point metal material may be simply expressed as the first metal material or the first layer.
Further, 4 is a first press surface (imprint master side), 5 is a second press surface (transfer plate side), 6 is a metal bonding layer, and 7 is an imprint master.

The imprint master 7 includes a mold 1 having a concavo-convex pattern, a first press surface 4 that supports the mold, and a low melting point metal material interposed between the mold 1 and the first press surface 4. It is comprised by the metal joining layer 6 formed by these.
Here, the metal bonding layer 6 is formed of two or more metal material layers, and the material of each layer is composed of metals or alloys having different melting points and types, and these include two types of metals or alloys. , More various multi-layer structures may be provided. In the first embodiment shown in FIG. 1, a layer made of the first low melting point metal material 2 and a layer made of the second low melting point metal material 3 having a melting point higher than that of the first low melting point metal material 2. Is formed.
In the first embodiment, the first low melting point metal material has a melting point in a high temperature range within 90 ° C. compared to the imprint temperature, and the second low melting point metal material has the second low melting point metal material. The melting point metal material has a melting point in a higher temperature range of 100 ° C. or more and 300 ° C. or less than the imprint temperature.
The first press surface 4 referred to here is one of a pair of press surfaces of a press used for imprinting, but is not necessarily integral with the press, such as metal, alloy, Si, or the like. A reinforcing plate made of a substrate may be used.

In the above configuration, the first low melting point metal material 2 of the metal bonding layer 6 serves to bond the mold 1 and the metal bonding layer 6 (adhesion function), and the second low melting point metal 3 is bonded to the metal. It plays the role of a buffer (buffer function) that absorbs the pressure distribution during imprinting due to adhesion between the layer 6 and the first press surface 4 and the film thickness distribution of the mold 1 or accidental scratches that occur during imprinting.
In order to make the second layer function as the buffer layer, it is preferable to make the second layer thicker than the first layer.
According to the first embodiment, both the bonding and buffer functions are obtained from two types of metal material layers having different melting points, and at the same time, a wider temperature can be obtained by such a multilayer metal material layer. Precise temperature control with good thermal conductivity can be achieved with respect to the area, and it is not necessary to replace the buffer layer every time imprinting is performed, so that high throughput can be achieved.

When imprinting is performed at 130 ° C., which is a typical temperature for imprinting, the first low melting point metal material 2 (first layer) is In having a melting point of 156 ° C. or a melting point of 150 ° C. to 220 ° C. The second low melting point metal material 3 (second layer) is more preferably Sn having a melting point of 231 ° C. or a solder having a melting point of 230 ° C. to 330 ° C. .
Here, the metal bonding layer 6 is installed on the back side of the concave / convex pattern region of the mold 1, and the area thereof is equal to or larger than the concave / convex pattern region of the mold 1.

Next, FIG. 2 shows the configuration of the second embodiment of the present invention, which is a preferable configuration of the master for imprinting. In FIG. 2, the same reference numerals are given to the components corresponding to those shown in FIG. 1, and the description of the overlapping parts is omitted.
In the second embodiment, the metal bonding layer 6 is made of the second low melting point metal material having a higher melting point than the first low melting point metal material by the layer 2 made of the first low melting point metal material. 3 is sandwiched between layers.
At this time, the first low melting point metal 2 in the upper layer plays a role of bonding to the first press surface 4 and the first low melting point metal 2 in the lower layer is bonded to the mold 1, respectively. 3 serves as a buffer that absorbs the film thickness distribution of the mold 1 and the pressure distribution during imprinting due to accidental scratches or the like that occur during imprinting.
Thus, according to the second embodiment, the layer 2 made of the first low-melting-point metal material can firmly perform the adhesion function, and the other second low-melting-point metal 3 having a different melting point can be used to form the buffer. In addition to being able to obtain functions, this multi-layered metal material layer enables precise temperature control with good thermal conductivity over a wider temperature range. Since there is no need to exchange layers, it is possible to achieve high throughput.

Next, a method for manufacturing an imprint master having the configuration shown in FIG. 1 according to the embodiment of the present invention will be described.
FIG. 3 is a process diagram illustrating a method for manufacturing an imprint master having the configuration shown in FIG.
First, using a press device having a first press surface 4 and a second press surface 5 as a pair of press surfaces, a mold 1, a layer made of a first low-melting-point metal material 2, a second low-melting-point metal material 3 and the press surface protecting substrate 8 are prepared (FIG. 3A).
Next, the layer made of the second low-melting-point metal material is bonded to the first press surface 4, and the first press-surface and the bonding component 9 made of the second low-melting-point metal material are produced ( FIG. 3 (b)).
Next, between the first press surface 4 and the second press surface 5, below the layer made of the second low melting point metal material, a layer made of the first low melting point metal material 2, the mold 1, and the press surface. The protective substrates 8 are installed in this order, and pressure is applied between the press surfaces at a temperature close to the melting point of the first low-melting-point metal material 2 (FIG. 3C). The pressure application condition at this time is preferably higher than the temperature at which imprinting is actually performed, and is applied at the time of imprinting at a temperature several tens of degrees lower than the melting point of the first low melting point metal material 2. Apply pressure.
Next, the pressure between the press surfaces is released to obtain an imprint master 7 (FIG. 3D).

Next, a method for manufacturing an imprint master having a more preferable configuration shown in FIG. 2 in the embodiment of the present invention will be described.
FIG. 4 is a process diagram for explaining a method of manufacturing an imprint master having the configuration shown in FIG.
First, a first press surface 4 and a second press surface 5 are used as a pair of press surfaces, and the first press surface 4 is interposed between these press surfaces from the first press surface 4 side. On the second press surface 5 in the order of the layer made of the low melting point metal material 2, the layer made of the second low melting point metal material 3, the layer made of the first low melting point metal material 2, the mold 1, and the press surface protecting substrate 8. Install in.
Next, a pressure is applied between the first press surface 4 and the second press surface 5 at a temperature close to the melting point of the first low melting point metal material 2 between the press surfaces. The pressure application condition at this time is preferably higher than the temperature at which imprinting is actually performed, and is applied at the time of imprinting at a temperature several tens of degrees lower than the melting point of the first low melting point metal material 2. Apply pressure.
Next, the pressure between the press surfaces is released to obtain an imprint master 7.

Here, without passing through the above creation process, for example, in the apparatus having the configuration shown in FIG. 3A, when a pressure plate is applied by installing a transfer plate instead of the press surface protection substrate 8, The first low-melting-point metal material 2 greatly extends when a pressure is applied, and the position of the mold 1 is shifted during the application of pressure, and scratches and distortion of the pattern occur during pattern transfer onto the transfer target plate.
Further, when the pressure application is performed at a lower temperature and lower pressure than the actual imprinting conditions without passing through the above-described production process, the first low melting point metal material 2 greatly extends during imprinting, and the position of the mold 1 is increased. Therefore, scratches and distortion of the pattern occur in the pattern transfer onto the transfer plate.

[Example 1]
In Example 1, an imprint master having the configuration shown in FIG. 1 was produced by applying the method for manufacturing an imprint master shown in FIG. 3 of the present invention.
Specifically, the mold 1 is a disk mold having a concavo-convex structure with a pitch of submicron and having a diameter of 2.5 inches by Ni plating, and the first low-melting-point metal material 2 is an Indium having a thickness of about 0.05 mm. A sheet, an Sn sheet having a thickness of about 0.1 mm as the second low-melting-point metal material 3, and an Al substrate having a thickness of 0.5 mm were prepared as a press surface protecting substrate. Here, the In sheet of the first low-melting point metal material 2 and the Sn sheet of the second low-melting point metal material 3 are prepared according to the pattern region of the mold 1. However, as for each melting | fusing point, In is 156 degreeC and Sn is 231 degreeC.

The Sn sheet of the second low-melting-point metal material 3 is placed on the first press surface 4 and the Sn sheet of the second low-melting-point metal material 3 and the first press at about 180 ° C. close to the melting point of Sn. The surface 4 was brought into close contact with each other, and the first press surface corresponding to 9 shown in FIG. 3B and the adhesion component 9 made of the Sn sheet of the second low melting point metal material 3 were produced.
Next, an Al substrate 8 for protecting the press surface, a mold 1 and an In sheet of the first low melting point metal material 2 are installed on the second press surface 5 in this order as shown in FIG. did.
Next, the pressure between the first press surface 4 and the second press surface 5 is equal to or higher than the imprint temperature at a temperature higher than the actual imprint temperature and several tens of degrees lower than the melting point of In. Was applied. In this example, a pressure was applied at 130 ° C. and 750 kgf / cm ² to produce an imprint master shown in FIG.

At this time, if only the In sheet is used for the adhesive layer, the In extends and escapes when pressure is applied, the amount remaining on the back surface of the pattern portion decreases, the buffer effect of the metal bonding layer becomes insufficient, and imprinting Problems such as breakage of the transferred plate occur.
In addition, when a resin sheet is used as an alternative to the metal layer, the film thickness distribution of the master for imprinting cannot be sufficiently compensated, causing accidental deflection and conversely, the uniformity of the applied pressure during imprinting decreases. The phenomenon occurs. Furthermore, when a resin sheet is used, it takes time to adjust the temperature of the imprinting master due to low thermal conductivity.
Further, when Al (melting point: 660 ° C.) is used instead of In, the imprint master and the metal adhesive layer cannot be bonded, and misalignment occurs during imprinting.

Further, if the In film thickness is less than 1 μm, the imprint master and the metal adhesive layer cannot be sufficiently bonded, resulting in misalignment during imprinting.
When the In film thickness is made larger than 100 μm, a large distortion occurs due to the film thickness distribution of the In film, and a large amount of In is discharged from the metal bonding layer when pressure is applied.
Further, when Al (melting point: 660 ° C.) is used instead of Sn, a sufficient buffer effect cannot be obtained, and there arises a problem that the transfer plate breaks during imprinting.
If the Sn film thickness is less than or equal to the film thickness distribution width of the master for imprinting, a sufficient buffer effect cannot be obtained, causing problems such as cracking of the transferred plate during imprinting.

  On the other hand, when imprinting is performed using the imprinting master produced in this example, the durability of the imprinting master is increased by reinforcement, and cracks of the transferred plate are suppressed to 1/10 or less. As a result, the temperature could be adjusted smoothly.

The means for joining the Sn sheet of the second low melting point metal material 3 to the first press surface 4 is not limited to the means described in the first embodiment, and sputtering, vapor deposition, plating, or resin is used. The same effect can be obtained by using a film formed on the press surface by attaching a sheet using an adhesive or an adhesive. Further, the same effect can be obtained by using solder formed by sputtering, vapor deposition, plating, or sheet attachment instead of the Sn sheet of the second low melting point metal material 3 used in Example 1.
Further, the In of the first low melting point metal material 2 bonded to the mold 1 used in Example 1 is the same as that of the second low melting point metal material 3 formed on the back surface of the mold 1 or the first press surface 4. The same effect can be obtained by using a film formed by sputtering, vapor deposition, plating, sheet bonding, or the like on the Sn film.
In addition, instead of In of the first low melting point metal material 2 to be attached to the mold 1 used in Example 1, the second low melting point metal material formed on the back surface of the mold 1 or on the first press surface 4 is used. The same effect can be obtained even when a solder film formed by sputtering, vapor deposition, plating, sheet pasting, or the like is used on Sn of 3.

[Example 2]
In Example 2, an imprint master having the configuration shown in FIG. 2 was produced by applying the method for manufacturing an imprint master shown in FIG. 4 of the present invention.
First, a first press surface 4 and a second press surface 5 are used as a pair of press surfaces, and the first press surface 4 is interposed between these press surfaces from the first press surface 4 side. As shown in FIG. 4, a layer made of the low-melting-point metal material 2, a layer made of the second low-melting-point metal material 3, a layer made of the first low-melting-point metal material 2, the mold 1, and the press surface protection substrate 8. It is installed on the second press surface 5.
Next, the pressure between the first press surface 4 and the second press surface 5 is equal to or higher than the imprint temperature at a temperature higher than the actual imprint temperature and several tens of degrees lower than the melting point of In. Was applied.
In this example, pressure was applied at 130 ° C. and 750 kgf / cm ² to produce the imprint master shown in FIG.

  According to the master for imprint produced in this example, the adhesion between the metal adhesive layer 6 and the first press surface 4 is strengthened, so that the same effect as that of Example 1 can be obtained at the time of imprint. The durability can be improved several times as much as in Example 1, and the lower limit of the corresponding imprint temperature range can be expanded by several tens of degrees.

Note that the In of the first low melting point metal material 2 attached to the back of the first press surface 4 and the mold 1 used in Example 2 was sputtered on the first press surface 4 and the back surface of the imprint master, Alternatively, the same effect can be obtained by using a film formed by vapor deposition, plating, sheet attachment, or the like.
Further, instead of In of the first low melting point metal material 2 attached to the back of the first press surface 4 and the mold 1 used in Example 2, the first press surface 4 and the back surface of the mold 1 are used. The same effect can be obtained even when a solder film formed by sputtering, vapor deposition, plating, sheet pasting, or the like is used.

The schematic diagram which shows the structure of 1st Embodiment of the master for imprint in embodiment of this invention. The schematic diagram which shows the structure of 2nd Embodiment of the master for imprint in embodiment of this invention. Process drawing explaining the manufacturing method of the master for imprint of the structure shown in FIG. 1 in embodiment and Example 1 of this invention. Process drawing explaining the manufacturing method of the master for imprint of the structure shown in FIG. 2 in embodiment and Example 2 of this invention.

Explanation of symbols

1: Mold 2: First low-melting-point metal material 3: Second low-melting-point metal material 4: First press surface (on imprint master side)
5: Second press surface (transfer plate side)
6: Metal bonding layer 7: Master substrate for imprint 8: Substrate for protecting the press surface 9: Bonding component made of the first press surface and the second low melting point metal material

Claims (8)

A mold having a concavo-convex pattern, a mold support substrate for supporting the mold, and an imprint master provided with a metal bonding layer between the mold and the mold support substrate,
The metal bonding layer includes a first layer configured to include a first metal material from the mold side, and a second layer configured to include a second metal material having a melting point higher than that of the first metal material. An imprinting master having a layer.   2. The imprint master according to claim 1, wherein a thickness of the second layer is larger than a thickness of the first layer.   2. The imprint master according to claim 1, wherein the first metal material has a layer thickness of 1 μm to 100 μm.   2. The imprint master according to claim 1, wherein the thickness of the second layer is equal to or greater than the thickness distribution of the master having the uneven pattern. The master for imprinting according to any one of claims 1 to 4 , wherein the first metal material is In or solder, and the second metal material is Sn or solder. An imprinting master and a pair of press surfaces are provided, and pressure is applied by sandwiching the imprinting master and the transferred plate between the pair of press surfaces, and the uneven pattern of the imprinting master is transferred to the transferred plate. In the imprint apparatus for transferring to
An imprint apparatus, wherein the imprint master is constituted by the imprint master according to any one of claims 1 to 5 . In an imprint apparatus comprising an imprint master, applying pressure by sandwiching the imprint master and a transferred plate between a pair of press surfaces, and transferring the uneven pattern of the imprint master to the transferred plate ,
6. An imprint apparatus, wherein one press surface of the pair of press surfaces is constituted by the mold support substrate of the imprint master according to any one of claims 1 to 5 . A first layer composed of a mold having a concavo-convex pattern, a first metal material interposed between the mold and one press surface of the pair of press surfaces, and a melting point higher than that of the first metal material A method for manufacturing an imprint master having a second layer composed of a high second metal material,
Bonding the second layer to one press surface of the pair of press surfaces;
Between the second layer and the other press surface of the pair of press surfaces, the first layer and the mold, the first layer as the second layer side, and unevenness of the mold Installing the pattern area as the other press surface side;
The second low pressure material bonded to the one press surface by applying a pressure between the pair of press surfaces at a temperature closer to the melting point of the first metal material than the second metal material. Bonding the mold to the layer made of the melting point metal material through the layer made of the first low melting point metal material;
A method for producing an imprint master, comprising:

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