CN210757122U - a retaining ring - Google Patents

Abstract

The utility model discloses a retaining ring, including first annular portion and second annular portion, first annular portion is made by metal material, second annular portion is made by non-metal material, the at least one side and the second annular portion of first annular portion are hugged closely fixedly.

Description

a retaining ring

technical field

The utility model belongs to the technical field of chemical mechanical polishing, in particular to a retaining ring.

Background technique

Chemical mechanical polishing is an acceptable method for global polishing of substrates. In this polishing method, the substrate is usually attracted to the lower part of the carrier head, the bottom surface of the substrate with the deposited layer abuts the rotating polishing pad, and the carrier head is driven by the driving component to rotate in the same direction as the polishing pad and give the substrate a downward load At the same time, the polishing liquid is supplied between the polishing pad and the substrate to realize the thinning of the substrate under the combined action of chemistry and machinery.

The lower part of the carrier head is provided with a retaining ring, which plays an important role in substrate polishing. On the one hand, it can prevent the substrate during the polishing process from flying out from the bottom of the carrier head; on the other hand, the bottom of the retaining ring is provided with a groove, which can renew the polishing liquid between the substrate and the polishing pad; Pressing on the polishing pad participates in the adjustment of the edge pressure of the substrate, which is beneficial to realize the global planarization of the substrate.

The existing retaining ring generally includes a metal part and a non-metal part, which are glued together by an adhesive, the metal part is connected with the base of the bearing head, and the non-metal part is in contact with the rotating polishing pad. The gluing of metal parts and non-metal parts has the risk of separation, and the gluing process of the adhesive increases the manufacturing cost of the retaining ring and affects the cost of chemical mechanical polishing of the substrate.

Therefore, there is an urgent need to design a retaining ring to solve the technical problems existing in the prior art.

Utility model content

The utility model aims to solve one of the technical problems existing in the prior art at least to a certain extent. To this end, the present utility model discloses a retaining ring, comprising a first annular portion and a second annular portion, the first annular portion is made of a metal material, the second annular portion is made of a non-metallic material, so At least one side of the first annular portion is tightly attached and fixed to the second annular portion.

Preferably, the inner side surface, outer side surface, bottom surface and/or top surface of the first annular portion are provided with a snap-fit structure.

Preferably, the inner surface, outer surface, bottom surface and/or top surface of the first annular portion are provided with nano-scale micropores.

Preferably, the engaging structure is a groove and/or a protrusion.

Preferably, the grooves and protrusions are arranged at intervals on the inner side surface, outer side surface, bottom surface and/or top surface of the first annular portion.

The retaining ring disclosed in the present application has the beneficial effects of ingenious design, stable structure and low manufacturing cost.

Description of drawings

The advantages of the present invention will become clearer and easier to understand by the detailed description in conjunction with the following drawings, which are only schematic and do not limit the protection scope of the present invention, wherein:

1 is a top view of the chemical mechanical polishing equipment according to the present invention;

FIG. 2 is a schematic structural diagram of the polishing unit according to the present invention;

3 is a schematic structural diagram of the carrying head according to the present invention;

FIG. 4 is a disassembled view of components according to an embodiment of the retaining ring according to the present invention;

Fig. 5 is a sectional view corresponding to the retaining ring of Fig. 4;

FIG. 6 is a disassembled view of components according to another embodiment of the retaining ring according to the present invention;

FIG. 7 is a cross-sectional view corresponding to the retaining ring of FIG. 6;

FIG. 8 is a disassembled view of another embodiment of the retaining ring according to the present invention;

Fig. 9 is a sectional view corresponding to the retaining ring of Fig. 8;

10 is a schematic structural diagram of a first annular portion according to the present invention;

FIG. 11 is a disassembled view of components according to another embodiment of the retaining ring according to the present invention;

Figure 12 is a cross-sectional view of the retaining ring corresponding to Figure 11;

Fig. 13 is a disassembled view of the components of another embodiment of the retaining ring according to the present invention;

Figure 14 is a cross-sectional view of the retaining ring corresponding to Figure 13;

15 and 16 are flowcharts of the manufacturing process of the retaining ring according to the present invention.

Among them, the meanings of the numerical reference signs are as follows:

1- Front-end module;

2-polishing unit; 2A-1st polishing unit; 2B-2nd polishing unit; 2C-3rd polishing unit; 2D-4th polishing unit;

3- Cleaning unit;

4- control unit;

10-polishing disc;

20 - polishing pad;

30-wafer carrier device;

31-carrying head; 32-upper pneumatic assembly;

311 - base body; 312 - retaining ring; 3121 - first annular part; 31211 - groove; 31212 - protrusion; 3122 - second annular part;

40-trimming device; 41-trimming arm; 42-trimming head;

50-Polishing liquid supply device.

Detailed ways

The technical solutions of the present utility model will be described in detail below with reference to the specific embodiments and the accompanying drawings. The embodiments described herein are specific specific implementations of the present invention, and are used to illustrate the concept of the present invention; these descriptions are all explanatory and exemplary, and should not be construed as a description of the embodiments of the present invention and the present invention. Limitation of the scope of protection. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the content disclosed in the claims of the present application and the description thereof, and these technical solutions include adopting any modifications made to the embodiments described herein. Obvious alternative and modified technical solutions.

The accompanying drawings in this specification are schematic diagrams, which assist in explaining the concept of the present invention, and schematically show the shapes of various parts and their mutual relationships. It should be understood that, in order to clearly represent the structure of each component of the embodiments of the present invention, the drawings are not drawn according to the same scale, and the same reference numerals are used to represent the same parts in the drawings.

1 is a top view of the overall structure of a chemical mechanical polishing equipment. The chemical mechanical polishing equipment includes a front-end module 1, a polishing unit 2, a cleaning unit 3 and a control unit 4. The front-end module 1, the polishing unit 2 and the cleaning unit 3 are independently set. The control unit 4 controls the substrate processing operation.

The front-end module 1 is provided with two or more front loading sections in which substrate cassettes for storing a plurality of substrates such as semiconductor wafers are placed, and the front loading sections are arranged in the width direction of the chemical mechanical polishing equipment. On the front loading part, an open box, a standard manufacturing interface box (SMIF, Standard Manufacturing Interface), or a front opening pod (FOUP, Front Opening Unified Pod) can be mounted. Here, SMIF and FOUP are airtight containers in which a substrate cassette is accommodated and an environment independent from the external space can be maintained by covering with a partition.

On the front-end module 1, a traveling mechanism is laid side by side along the front loading portion, and a conveying robot movable in the direction in which the substrate cassettes are arranged is arranged on the traveling mechanism. The transport robot can access the substrate cassette mounted on the front loading unit by moving on the traveling mechanism. The conveying robot has upper and lower hands. The upper hand is used to return the processed substrate to the substrate cassette, and the lower hand is used to remove the unprocessed substrate from the substrate cassette. Front-end module 1 is the cleanest area for chemical mechanical polishing. Therefore, the interior of front-end module 1 is always maintained at a higher pressure than that of polishing unit 2 and cleaning unit 3 to prevent airflow from other areas from entering front-end module 1. The front-end module 1 is provided with a filter fan unit having a clean air filter such as a HEPA filter, a ULPA filter, or a chemical filter, and clean air from which particulates are removed is always blown from the filter fan unit.

The polishing unit 2 is an area for chemical mechanical polishing of the surface of the substrate, and includes a first polishing unit 2A, a second polishing unit 2B, a third polishing unit 2C, and a fourth polishing unit 2D. The first polishing unit 2A, the second polishing unit 2B The polishing unit 2B, the third polishing unit 2C, and the fourth polishing unit 2D are arranged along the longitudinal direction of the chemical mechanical polishing apparatus.

The cleaning unit 3 includes a cleaning module and a drying module. The cleaning module includes a driving component and a cleaning component. When the driving component drives the substrate to rotate, the cleaning component swings around an axis perpendicular to the surface of the substrate to spray fluid on the surface of the substrate. For example, when the substrate surface is cleaned by spraying deionized water or chemicals on the substrate surface with the cleaning component, the substrate rotates, and the particles on the substrate surface can be removed by the action of centrifugal force. Compared with the existing brush and megasonic cleaning methods, The method of rinsing the surface of the substrate with liquid causes less damage, and because it does not need to use other components to contact the substrate, the consumables will not become dirty after the service life, thereby secondary contamination of the substrate surface. The drying module and the cleaning module are arranged side by side, wherein the drying module is used to dry the substrate, remove the liquid on the surface of the substrate, and prevent the droplets attached to the surface of the substrate from producing water stains on the surface of the substrate during the natural drying process, thereby ensuring the stability of the substrate. cleaning effect. In some embodiments, the cleaning module can also choose a brush and/or megasonic cleaning method, which is arranged on the outside of the polishing unit 2 side by side with the drying module.

Since the first polishing unit 2A, the second polishing unit 2B, the third polishing unit 2C, and the fourth polishing unit 2D have the same structure, the first polishing unit 2A will be described below. 2 is a perspective view of the first polishing unit 2A. The polishing unit 2A includes a polishing disk 10, a polishing pad 20, a wafer carrier 30, a dressing device 40 and a polishing liquid supply device 50; the polishing pad 20 is disposed on the upper surface of the polishing disk 10 and It rotates along the axis Ax1 together with it; the horizontally movable wafer carrier 30 is disposed above the polishing pad 20, and its lower surface holds the wafer W to be polished; the trimming device 40 includes a trimming arm 41 and a trimming head 42, and the trimming arm 41 drives the rotating trimming head 42 to swing so as to trim the surface of the polishing pad 20 to a state suitable for polishing; the polishing liquid supply device 50 spreads the polishing liquid on the surface of the polishing pad 20; The surface to be polished is pressed against the surface of the polishing pad 20 , the polishing liquid is distributed between the polishing pad 20 and the wafer W, and the surface material of the wafer is removed under the action of chemical machinery. The wafer carrier 30 includes a carrier head 31 and an upper pneumatic assembly (UPA, upperpneumatic assembly) 32 . The carrier head 31 is coupled to the upper pneumatic assembly 32 through a connecting assembly not shown.

3 is a schematic diagram of the structure of the carrier head 31. The carrier head 31 includes a base body 311 and a retaining ring 312 disposed at the bottom of the base body 311. An elastic film is provided inside the base body 311, and the elastic film and the base body form independent chambers. In order to hold the substrate to be polished, the holding ring 312 is located at the outer side of the elastic film, and a gap is provided between the elastic film and the inner side of the holding ring 312 .

As shown in FIG. 4 , the retaining ring includes a first annular portion 3121 and a second annular portion 3122 , which are combined and formed into one body. 5 is a sectional view of the retaining ring, the first annular portion 3121 is integrally covered by the second annular portion 3122, the first annular portion 3121 is made of a metal material, the second annular portion 3122 is made of a non-metallic material, and the first annular portion 3121 is made of a non-metallic material. The bottom surface and side surface of the first annular portion 3121 are closely fitted with the second annular portion 3122. The side surface of the first annular portion 3121 is provided with a groove 31211, and the bottom surface of the first annular portion 3121 is provided with a protrusion 31212 to increase the first annular portion 3121. Contact area with the second annular portion 3122 . As a variation of this embodiment, a plurality of grooves 31211 and/or protrusions 31212 may be provided on the side and bottom surfaces of the first annular portion 3121 to increase the degree of coupling between the first annular portion 3121 and the second annular portion 3122 .

As an embodiment of the present invention, the bottom surface and the side surface of the first annular portion 3121 are provided with nano-scale micropores, and the non-metallic material constituting the second annular portion 3122 is in a molten state, and is directly injected into the molding die to melt the The state-of-the-art non-metallic material directly enters the nano-pore, which effectively ensures the bonding strength of the first annular portion 3121 and the second annular portion 3122 .

The top surface of the first annular portion 3121 is provided with threaded holes (not shown), and the retaining ring is connected and fixed with the base of the bearing head through the threaded holes. In some embodiments, the first annular portion 3121 may be made of metal such as stainless steel, titanium alloy or aluminum alloy, and the second annular portion 3122 may be made of PPS, PEEK, polycarbonate, polyurethane, polyurethane, or PET, etc. Made of non-metallic materials. Preferably, the second annular portion 3122 is made of non-metallic materials such as PPS, PEEK, etc., which are inert materials, have no effect on the chemical mechanical polishing process, and have sufficient elasticity to prevent chipping or cracking of the edge of the substrate.

As an embodiment of the present invention, the bottom surface of the second annular portion 3122 is provided with a plurality of flow grooves, and the flow grooves are provided through the inner surface to the outer surface of the second annular portion 3122, and the polishing liquid used for chemical mechanical polishing passes through The flow groove enters between the substrate and the polishing pad, and the polishing liquid used for polishing flows out through the flow groove, and the polishing liquid realizes self-renewal through the flow groove of the second annular portion 3122 to ensure the smooth progress of chemical mechanical polishing.

6 is a disassembled view of the components of another embodiment of the retaining ring 312 of the present invention, the first annular portion 3121 is made of metal material, the second annular portion 3122 is made of non-metallic material, and the first annular portion 3121 is made of The side surface and the bottom surface are in close contact with the second annular portion 3122 and are integrated into one through nano-molding. 7 is a cross-sectional view of the retaining ring, the side of the first annular portion 3121 is a tapered surface, and a plurality of nano-pores are arranged on it. The bonding strength of the first annular portion 3121 and the second annular portion 3122 .

8 is a disassembled view of an embodiment of the retaining ring 312 according to the present invention. The side, bottom and top surfaces of the first annular portion 3121 are closely attached to the second annular portion 3122 and integrated into one through nano-molding. 9 is a cross-sectional view of the retaining ring, the bottom surface and the top surface of the first annular portion 3121 are provided with roughened structures to prevent the first annular portion 3121 from being separated from the second annular portion 3122, ie, a molten and/or semi-molten state. The non-metallic material is directly bonded to the metal support structure of the retaining ring to mold the desired retaining ring. FIG. 10 is a schematic diagram of the structure of the first annular portion 3121 . The bottom surface and the top surface of the first annular portion 3121 are provided with roughened structures with recesses and protrusions arranged at intervals. The cross-sectional shapes of the depressions and protrusions of the roughened structure are rectangles, and it can be understood that they can also be other shapes, such as circles, ellipses and/or triangles.

11 is a disassembled view of an embodiment of the retaining ring 312 of the present invention. The first annular portion 3121 is made of a metal material, the second annular portion 3122 is made of a non-metallic material, and the inner portion of the first annular portion 3121 is made of a metal material. The side surface and the bottom surface are in close contact with the second annular portion 3122 and are integrated into one through nano-molding. 12 is a cross-sectional view of the retaining ring, the inner side and bottom surface of the first annular portion 3121 are provided with nano-scale pores, and the non-metallic material in the molten state directly enters the nano-sized pores, so that the first annular portion 3121 and the second annular portion 3122 are closely In combination, no adhesive is needed, the bonding process is saved, and the processing and manufacturing cost of the retaining ring is reduced.

FIG. 13 is a disassembled view of an embodiment of the retaining ring 312 of the present invention. The first annular portion 3121 is made of a metal material, the second annular portion 3122 is made of a non-metallic material, and the bottom surface of the first annular portion 3121 is made of a metal material. It is in close contact with the second annular portion 3122 and integrated into one through nano-molding. 14 is a cross-sectional view of the retaining ring. The bottom surface of the first ring body portion 10 is provided with protrusions 31212, the top surface of the corresponding second ring portion 3122 is provided with a concave structure for engaging the protrusions 31212, and the bottom surface of the first ring portion 3121 is provided with a recessed structure. Nano-scale pores are provided to increase the combination of the first annular portion 3121 and the second annular portion 3122 and prevent the second annular portion 3122 from falling off from the first annular portion 3121 .

15 is a flow chart of the processing and manufacturing of the retaining ring 312 of the present invention. Step S11 is to process and manufacture the first annular portion 3121; Step S12 is to pretreat the first annular portion 3121. The embroidery layer on the surface of the first annular portion 3121 is removed by other means, and the first annular portion 3121 is cleaned and dried; step S13 is to form nano-scale micropores on the side, bottom or top surface of the first annular portion 3121; step S14 is to manufacture the second annular portion 3121. The annular portion 3122 is integrated with the first annular portion 3121. Specifically, the non-metal constituting the second annular portion 3122 is in a molten state and flows into the nano-pores of the first annular portion 3121, which effectively increases the difference between the two. Cohesion.

16 is a process flow chart of another embodiment of the retaining ring 312 of the present invention. Step S21 is to process and manufacture the first annular portion 3121 so that the side, top and/or bottom surfaces of the first annular portion 3121 are engaged with each other. Structure; step S22 is to pretreat the first annular portion 3121, specifically, use sandblasting, shot blasting, grinding and other means to remove the embroidery layer on the surface of the first annular portion 3121 and clean and dry the first annular portion 3121; Step S23 is to manufacture The second annular portion 3122 is integrated with the first annular portion 3121, and the non-metal constituting the second annular portion 3122 is in a molten state and flows to the first annular portion 3121. The engagement structure effectively increases the degree of integration between the two. .

In the description of this specification, reference to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples", etc., is intended to be combined with the description of the embodiment A particular feature, structure, material, or characteristic described by an example or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention. Variations, the scope of the present invention is defined by the claims and their equivalents.

Claims (5)

1. A retaining ring, characterized in that it comprises a first annular portion and a second annular portion, the first annular portion is made of a metal material, the second annular portion is made of a non-metallic material, and the first annular portion is made of a non-metallic material. At least one side of an annular portion is closely fixed to the second annular portion. 2 . The retaining ring according to claim 1 , wherein the inner side surface, outer side surface, bottom surface and/or top surface of the first annular portion are provided with engaging structures. 3 . 3 . The retaining ring according to claim 1 , wherein the inner side surface, outer side surface, bottom surface and/or top surface of the first annular portion are provided with nano-scale pores. 4 . 4. The retaining ring according to claim 2, wherein the engaging structure is a groove and/or a protrusion. 5 . The retaining ring of claim 4 , wherein the grooves and protrusions are arranged at intervals on the inner side surface, outer side surface, bottom surface and/or top surface of the first annular portion. 6 .

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