CHEMICAL MECHANICAL PLANARIZATION PAD WITH A RELEASE LINER COMPRISING A PULL TAB
A chemical mechanical polishing (CMP) pad with a release liner that has a pull tab is prepared by contacting the CMP pad to an adhesive layer with release liner. The adhesive layer sheet is cut along a first portion of a perimeter of the CMP pad. An extension of the adhesive layer is cut that extends beyond an edge of the CMP pad at the remaining portion of the perimeter of the CMP pad, thereby creating an extension of the adhesive layer sheet with the adhesive layer exposed. The exposed adhesive layer is cut to a depth not to extend into the release liner. The adhesive layer is removed from the exposed region leaving only the release liner pull tab as a continuous extension of the release liner material.
This disclosure generally relates to polishing pads used in chemical mechanical polishing, and more specifically to a chemical mechanical polishing pad with a release liner comprising a pull tab.
BACKGROUNDAn integrated circuit is typically formed on a substrate by the sequential deposition of conductive, semi-conductive, and/or insulative layers on a silicon wafer. A variety of fabrication processes require planarization of at least one of these layers on the substrate. For example, for certain applications (e.g., polishing of a metal layer to form vias, plugs, and lines in the trenches of a patterned layer), an overlying layer is planarized until the top surface of a patterned layer is exposed. In other applications (e.g., planarization of a dielectric layer for photolithography), an overlying layer is polished until a desired thickness remains over the underlying layer. Chemical-mechanical planarization (CMP) is one method of planarization. This planarization method typically involves a substrate being mounted on a carrier head. The exposed surface of the substrate is typically placed against a polishing pad that is attached to a rotating platen. The carrier head provides a controllable load (e.g., a downward force) on the substrate to push it against the rotating polishing pad. A polishing liquid, such as slurry with abrasive particles, can also be disposed on the surface of the polishing pad during polishing.
SUMMARYIn order to perform planarization processes, the chemical mechanical polishing (CMP) pad must be physically attached to the platen of a CMP system. To achieve this attachment, the underside of the CMP pad may include a platen adhesive layer. A platen adhesive release liner, or release liner, may cover the platen adhesive to protect this platen adhesive during storage and transport of CMP pads until the time of their use. When a user wishes to attach a CMP pad to the platen, they must first remove the release liner. Previous release liners are the same shape (e.g., a circular shape) and can be difficult to remove from the underside of the CMP pad. In some cases, attempts to remove the release liner can result in damage to the CMP pad. CMP pads having multiple layers (e.g., a top polishing layer, a subpad layer, and any intermediate adhesive layers) may be particularly susceptible to damage during the removal of previous release liners. For example, certain combinations of pad layer materials may be susceptible to separation or delamination of the CMP pad layers when a conventional release liner is removed. This may be more problematic for CMP pads having interlayer adhesion strengths that are less than or at a similar magnitude to the adhesion strength between the release liner and the platen adhesive on the underside of the CMP pad. Furthermore, the additional bulk that results when a separate adhesive tape is added as a pull tab prevents efficient stacking of the pads, for example during shipping. The added bulk in a stack of pads can lead to deformities in the pad, which can result in damage and/or reduced performance of the pad.
This disclosure provides a technical solution to the problems of previous CMP pad release liners, including those described above, by providing a CMP pad having a protective release liner with a pull tab. This CMP pad is better adapted for easy removal of the protective release liner. The pull tab is an extension of the release liner that extends beyond the edge of the CMP pad (see, e.g.,
In one embodiment, an article includes a chemical mechanical polishing (CMP) pad and a release liner. The CMP pad has a circular shape. The CMP pad includes a polishing layer and a platen adhesive layer. The release liner has a body portion and a pull tab. The body portion has substantially the same shape as the circularly shaped CMP pad. The body portion includes a release liner layer and an adhesive layer. The adhesive layer contacts the release liner layer of the CMP pad. The pull tab includes an extension of the release liner layer of the body portion that extends beyond an edge of the body portion (e.g., and beyond an edge of the CMP pad).
In another embodiment, a method of preparing a pull tab in a release liner contacting a CMP pad includes contacting the CMP pad to an adhesive layer of a sheet of the release liner. The sheet of the release liner includes the adhesive layer and a non-release liner layer. The method includes cutting the release liner sheet along a first portion of a perimeter of the CMP pad. The method includes cutting an extension of the release liner that extends beyond an edge of the CMP pad at the remaining portion of the perimeter of the CMP pad, thereby creating an extension of the release liner sheet with the adhesive layer exposed. The method includes contacting a surface to the exposed adhesive layer of the created extension of the release liner. The method includes removing the contacted surface from the exposed region, thereby removing the adhesive layer from the exposed region.
To assist in understanding the present disclosure, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:
It should be understood at the outset that, although example implementations of embodiments of the disclosure are illustrated below, the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should in no way be limited to the example implementations, drawings, and techniques illustrated below. Additionally, the drawings are not necessarily drawn to scale.
As described above, previous release liner technology can be difficult to remove from a CMP pad without damaging the CMP pad. This disclosure recognizes that attaching a separate material to the release liner to aid in removal of the release liner is unreliable and can still result in damage to the CMP pad. The unique continuous pull tab of this disclosure (see, e.g.,
The platen 104 can generally be rotated during chemical mechanical planarization. A wafer 106 (e.g., a silicon wafer with or without conductive, semi-conductive, and/or insulative layers, as described above) is attached to a head 108 of a rotatable chuck. The wafer 106 may be attached using vacuum and/or a reversible adhesive (e.g., an adhesive that holds the wafer 106 in place during chemical mechanical planarization but allows the wafer 106 to be removed from the head 108 after chemical mechanical planarization). During CMP processing, a slurry 110 may be provided on the surface of the CMP pad 102 before and/or during chemical mechanical planarization. The slurry 110 generally includes a fluid and particles that may be abrasive and/or chemically reactive. A conditioner 112 is a device which is configured to condition the surface of the CMP pad 102. Conditioning of the surface prepares the CMP pad 102 to be used for chemical mechanical planarization. The conditioner 112 generally conditions the surface by contacting the surface of the CMP pad 102 and removing a portion of the top layer of the CMP pad 102 to improve its performance during chemical mechanical planarization.
In order for these and other CMP processes to proceed according to expectations for a given CMP pad 102, the structure of the CMP pad 102 should not be altered or damaged when the pad 102 is being attached to the platen 104. A release liner is provided on the CMP pad 102 to protect platen adhesive. The release liner is removed to expose the platen adhesive and allow a user to attach the CMP pad 102 to the platen 104. Using previous technology there was a risk of damaging the CMP pad 102 when the release liner was removed. This disclosure provides an improved release liner that includes a pull tab that is a continuous component of the release liner sheet or film, as described further below.
Example CMP Pads with a Release Liner Having a Pull Tab
The polishing layer 204 may include polyurethane and/or any additives/fillers to improve polishing/planarization performance. The subpad layer 208 may be a foam or other more or less compressible layer. As an example, a subpad layer 208 may include polyurethane and any additives/fillers. The adhesive layer 206 generally includes any adhesive material(s) that can adhere to each of the connecting layers. For instance, adhesive layer 206 may include an adhesive material (e.g., glue, tape, etc.) that adheres to both the polishing layer 204 and the subpad layer 208. For instance, as shown in the example of
The release liner layer 218 includes the pull tab 202, which is an extension of the release liner layer 218 that extends beyond the edge 114 of the main body of the release liner 210 (e.g., edge 310 illustrated in
As described further below, this disclosure recognizes that certain multi-layered CMP pads 102 may be particularly susceptible to damage (e.g., separation and/or delamination of layers) when conventional release liners are removed. For example, using previous technology, the CMP pad 102 may separate at the polishing layer 204, the subpad layer 208, and/or any of the other layers 206 and 210. The pull tab 202 of this disclosure significantly reduces or eliminates occurrence of this type of inadvertent damage.
Example Release Liner ConfigurationsFor each of the configurations 300, 320, 340 shown in
For each of the configurations 300, 320, 340 shown in
Example Methods of Preparing CMP Pads with a Release Liner Having a Pull Tab
At step 404, the CMP pad 102 is contacted to a sheet of the platen adhesive material (e.g., a sheet that includes the layers 212-218 illustrated in
Referring to both
At step 408, the body portion 302 of the adhesive layer 510 (210) is cut from the sheet 510 (see
Referring to both
The extension 514 may be cut at step 410 manually or automatically using an automated cutting tool 502, as described with respect to step 408 above. In embodiments in which the extension 514 is cut manually, a cutting guide may be used. The cutting guide acts as a specialized stencil for cutting the extension 514 that will form the pull tab 202. An example cutting guide 600 is shown in
Returning to step 410 of
The unique pull tab 202 achieved via process 400 and that is a continuous extension of the release liner layer 218 that is also protecting the platen adhesive layer 216 of the CMP pad 102 may aid in preventing or eliminating damage to the CMP pads 102 when the release liner layer 218 is removed. The release liner layer 218 with pull tab 202 may particularly prevent damage to CMP pads 102 that have interlayer adhesion strengths (e.g., between the layers 204-208 of the CMP pad 102) that are less than the adhesion strength between the platen adhesive 212 on the underside of the CMP pad 102 and the release liner layer 218. This pull tab 202 that is formed as a continuous extension of the release liner layer 218 that protects the CMP pad 102 also facilitates improved storage and transportation of sets of CMP pads 102. For example, CMP pads 102 having release liners 218 with continuous pull tabs 202, as described in this disclosure, can be evenly or flatly stacked together without risk of damage. In contrast, if a separate pull tab were attached to the release liner, CMP pads would not stack evenly against each other. Instead, the added pull tabs would cause the CMP pads to stack at an angle relative to each other, resulting in an increased risk of damage during storage and transport.
Modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein. The components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses may be performed by more, fewer, or other components. The methods may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. Additionally, operations of the systems and apparatuses may be performed using any suitable logic. As used in this document, “each” refers to each member of a set or each member of a subset of a set.
Herein, “or” is inclusive and not exclusive, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A or B” means “A, B, or both,” unless expressly indicated otherwise or indicated otherwise by context. Moreover, “and” is both joint and several, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A and B” means “A and B, jointly or severally,” unless expressly indicated otherwise or indicated otherwise by context.
The scope of this disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments described or illustrated herein that a person having ordinary skill in the art would comprehend. The scope of this disclosure is not limited to the example embodiments described or illustrated herein. Moreover, although this disclosure describes and illustrates respective embodiments herein as including particular components, elements, feature, functions, operations, or steps, any of these embodiments may include any combination or permutation of any of the components, elements, features, functions, operations, or steps described or illustrated anywhere herein that a person having ordinary skill in the art would comprehend. Furthermore, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. Additionally, although this disclosure describes or illustrates particular embodiments as providing particular advantages, particular embodiments may provide none, some, or all of these advantages.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better explain the disclosure and does not pose a limitation on the scope of claims.
Claims
1. An article, comprising:
- a chemical mechanical polishing pad having a circular shape, the chemical mechanical polishing pad comprising a polishing layer; and
- a release liner comprising: a body portion having substantially the same shape as the circularly shaped chemical mechanical polishing pad, wherein the body portion comprises a release liner layer and an adhesive layer, wherein the adhesive layer is in contact with the chemical mechanical polishing pad; and a pull tab comprising an extension of the release liner layer of the body portion that extends beyond an edge of the chemical mechanical polishing pad.
2. The article of claim 1, wherein:
- the body portion further comprises: a carrier film layer contacting the adhesive layer; a secondary adhesive layer contacting the carrier film layer; and
- the release liner layer is contacting the secondary adhesive layer.
3. The article of claim 2, wherein the pull tab comprises the extension of the release liner layer of the body portion without the adhesive layer, carrier film layer, and the secondary adhesive layer.
4. The article of claim 1, wherein the release liner layer of the body portion and the pull tab form a continuous sheet of material.
5. The article of claim 1, wherein the release liner layer comprises one of a polyester film, kraft paper, or any other material protecting the adhesive layer.
6. The article of claim 1, wherein the pull tab has a semicircular shape.
7. The article of claim 1, wherein the pull tab has a rectangular shape.
8. The article of claim 1, wherein the pull tab is configured to decrease occurrence of damage to the chemical mechanical polishing pad when the release liner layer is removed from the chemical mechanical polishing pad.
9. The article of claim 1, further comprising a plurality of pull tabs, each pull tab comprising an extension of the release liner layer of the body portion that extends beyond the edge of the body portion.
10. The article of claim 1, wherein the pull tab comprises a width along the edge of the body portion and a length directed away from the edge of the body portion, wherein the width and length are a predefined fraction of a characteristic size of the chemical mechanical polishing pad.
11. A method for preparing a pull tab in a release liner for a chemical mechanical polishing pad, the method comprising:
- providing the chemical mechanical polishing pad;
- contacting the chemical mechanical polishing pad to a sheet of adhesive material, the sheet of the adhesive material comprising an adhesive layer and a release liner layer;
- cutting the sheet of adhesive material along a first portion of a perimeter of the chemical mechanical polishing pad;
- cutting an extension of the adhesive material that extends beyond an edge of the chemical mechanical polishing pad at the remaining portion of the perimeter of the chemical mechanical polishing pad, thereby creating an extension of the adhesive material with the adhesive layer exposed;
- contacting a surface to the exposed adhesive layer of the created extension of the adhesive material; and
- removing the contacted surface from the exposed adhesive layer, thereby removing the adhesive layer from the extension of the release liner and forming the pull tab.
12. The method of claim 11, wherein a length of the remaining portion of the perimeter of the edge of the chemical mechanical polishing pad is a predefined fraction of a characteristic size of the chemical mechanical polishing pad.
13. The method of claim 11, further comprising, before contacting the surface to the exposed adhesive layer, cutting along the remaining portion of the perimeter of the chemical mechanical polishing pad at a decreased depth such that the release liner layer is not cut through along the remaining portion of the perimeter of the chemical mechanical polishing pad.
14. The method of claim 11, wherein steps of cutting the adhesive material along the first portion of the perimeter of the chemical mechanical polishing pad and cutting the extension of the adhesive material are performed using an automated cutting tool.
15. The method of claim 11, wherein the pull tab is configured to decrease occurrence of damage to the chemical mechanical polishing pad when the release liner layer is removed from the chemical mechanical polishing pad.
16. The method of claim 11, wherein cutting the adhesive material along the first portion of the perimeter of the chemical mechanical polishing pad comprises manually cutting along the edge of the chemical mechanical polishing pad.
17. The method of claim 16, wherein cutting the extension of the adhesive material that extends beyond the edge of the chemical mechanical polishing pad comprises:
- providing a cutting guide comprising an alignment edge configured to align with the edge of the chemical mechanical polishing pad and an extension-design edge defining a shape of the to-be-cut extension of the adhesive material;
- contacting the alignment edge of the cutting guide to the edge of the chemical mechanical polishing pad at the remaining portion of the perimeter of the chemical mechanical polishing pad; and
- manually cutting along the extension-design edge of the cutting guide.
18. The method of claim 11, further comprising, prior to removing the contacted surface from the exposed adhesive material, applying force to the surface.
19. The method of claim 11, wherein the release liner layer is a polyester film, kraft paper, or other material protecting the adhesive material.
20. The method of claim 11, wherein:
- the chemical mechanical polishing pad comprises a polishing layer and a subpad layer; and
- an adhesion strength between the polishing layer and the subpad layer is less than an adhesion strength between the subpad layer and the adhesive layer of the adhesive material.
Type: Application
Filed: Sep 17, 2021
Publication Date: Mar 23, 2023
Inventors: Justin Stewart (Aurora, IL), Gary Snider (Oswego, IL), Carlos Barros (West Chicago, IL)
Application Number: 17/478,690