Adhesive sheet for fixing polishing pads and method for manufacturing the same

Abstract

To provide a double-sided adhesive sheet with a release liner for fixing polishing pads to a surface plate, for high-precision CMP machining, which allows for easy repositioning, has excellent air release properties, and has superior adhesive properties, for fixing polishing pads to a surface plate. [Solution] An adhesive sheet for fixing a polishing pad with a release sheet FA, wherein one side of the sheet-like substrate has an adhesive layer A, and the other side of the sheet-like substrate has an adhesive layer B, and the surface of the adhesive layer A that is not in contact with the sheet-like substrate is in contact with the release sheet FA, wherein the outer surface of the release sheet FA that is not in contact with the adhesive layer A has irregularities, and in a Beck smoothness test, the smoothness of the outer surface of the release sheet FA as determined by specific condition 1 is 0.1 to 30 seconds, and the smoothness of the outer surface of the release sheet FA as determined by specific condition 2 is 1 to 500 seconds.

Description

Technical Field

[0001] The present invention relates to an adhesive sheet with a release sheet, in which an adhesive layer for fixing a polishing pad to a surface plate is covered with the release sheet. The present invention also relates to a polishing pad with an adhesive layer having a specific adhesive layer and a polishing pad. The present invention also relates to a polishing pad with a release sheet and an adhesive layer having a release sheet, a specific adhesive layer, and a polishing pad. The present invention also relates to a method for fixing a polishing pad to a surface plate through a specific adhesive layer.

Background Art

[0002] In recent years, for the development of semiconductors, higher integration and higher quality are required, and higher polishing accuracy is also required for wafers as materials. There is a method of polishing by altering only the surface using a chemical reaction such as CMP (Chemical Mechanical Polishing), not only by excavation with simple abrasive grains. In CMP as well, development of techniques for obtaining a smoother polishing surface than before is in progress. When attaching a polishing pad to a surface plate, a double-sided adhesive sheet is used. Specifically, one side of the double-sided adhesive sheet is attached to one side of the polishing pad (the side opposite to the side where the object to be polished is to be polished), a polishing pad with a single-sided adhesive layer is prepared in advance, and the adhesive layer of the polishing pad with the single-sided adhesive layer is attached to the surface plate.

[0003] Various adhesive sheets for fixing polishing pads have been proposed (such as Patent Documents 1 to 3, etc.).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

[0005] Polishing pads are required in various forms depending on the polishing stage, and those used for the final finishing stage, in particular, are increasingly complex in structure, with multiple layers of varying hardness and thickness. The more complex the structure of the polishing pad, the more difficult it becomes to attach it to the polishing plate. When attaching a highly multi-layered, thick, single-sided adhesive polishing pad to a surface plate, achieving the desired position often requires repeated adjustments such as temporary attachment, position confirmation, peeling, and reattachment. From a productivity standpoint, it is desirable to minimize the time and frequency of these adjustments. In terms of ease of adjustment, using an adhesive layer with low tack strength is effective. However, the adhesive layer used to fix the polishing pad to the surface plate requires strong tackiness and cohesive force (holding force) sufficient to withstand polishing.

[0006] Furthermore, even if a polishing pad with an adhesive layer on one side could be quickly and temporarily fixed to the target position on the surface plate, there was a problem of air trapped between the surface plate and the adhesive layer when the polishing pad was firmly fixed to the surface plate using rollers or a press. If air trapped between the surface plate and the adhesive layer remained locally, the parallelism between the outermost surface of the polishing pad and the surface plate would be impaired, making it impossible to polish the object to be polished with high precision and smoothness, thus affecting the polishing accuracy. One possible method to suppress air entrapment is to create grooves on the surface of the adhesive layer that contacts the surface plate, which serve as air passages. However, even with air passages, when the polishing pad is firmly fixed to the surface plate, the air passages can be blocked by the soft adhesive layer, making it impossible to completely eliminate the voids. If it takes a long time for the air to escape, it can slow down the semiconductor production speed.

[0007] The adhesive layer of the double-sided adhesive sheet used to fix the polishing pad to the surface plate requires strong adhesive strength, cohesive force (holding power) to withstand the shear force applied during the polishing process, and chemical resistance such as resistance to strong alkalis and strong acids to the polishing solutions used during polishing. In particular, CMP often uses strong alkaline polishing solutions, so strong alkali resistance is required.

[0008] This invention has been made in view of the above background, and aims to provide a double-sided adhesive sheet for fixing polishing pads to a surface plate for high-precision CMP processing, which is easy to reposition, has excellent air release properties, and has excellent adhesive properties. [Means for solving the problem]

[0009] The present invention solves the above problems by setting the smoothness of the outer surface of the release sheet FA to a predetermined range. That is, the present invention relates to the following [1] to

[14] .

[0010] [1] The present invention relates to an adhesive sheet for fixing a polishing pad to a surface plate, comprising an adhesive layer A on one side of a sheet-like substrate, an adhesive layer B on the other side of the sheet-like substrate, and the surface of the adhesive layer A that is not in contact with the sheet-like substrate being in contact with a release sheet FA, wherein the adhesive sheet for fixing a polishing pad has a release sheet FA, The material of the aforementioned release sheet FA is a plastic film that does not contain paper. The outer surface of the release sheet FA that is not in contact with the adhesive layer A has irregularities, and in the Beck smoothness test, The smoothness of the outer surface of the release sheet FA, as determined by the following condition 1, is 0.1 to 30 seconds. The smoothness of the outer surface of the release sheet FA, as determined by condition 2 below, is 15 to 500 seconds. The present invention relates to an adhesive sheet for fixing polishing pads, characterized by the following features. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: Time taken for the pressure to change from -50.7 kPa to -29.3 kPa.

[0011] [2] The present invention relates to an adhesive sheet for fixing a polishing pad with a release sheet FA as described in [1], characterized in that the average height Rc of the surface irregularities on the outer surface of the release sheet FA is 12 to 42 μm. [3] The present invention relates to an adhesive sheet for fixing a polishing pad with a release sheet FA as described in [1] or [2] above, characterized in that the cutting level difference Rδc of the contour curve of the surface irregularities on the outside of the release sheet FA is 5 to 25 μm and the kurtosis Rku is less than 3. [4] The present invention relates to an adhesive sheet for fixing a polishing pad with a release sheet FA as described in any of [1] to [3] above, characterized in that the shape of the convex portion on the outer surface of the release sheet FA is irregular and irregular in plan view. [5] The present invention relates to an adhesive sheet for fixing a polishing pad with a release sheet FA as described in any of [1] to [4] above, characterized in that the adhesive layer A is an acrylic adhesive layer.

[0012] [6] The present invention comprises an adhesive sheet for fixing a polishing pad with a release sheet FA as described in any of [1] to [5] above, and a release sheet FB, The release sheet FB is in contact with the side of the adhesive layer B that is not in contact with the sheet-like substrate. The present invention relates to a release sheet FA and an adhesive sheet for fixing a polishing pad with a release sheet FB, characterized in that the material of the release sheet FB is a plastic film that does not contain paper.

[0013] [7] The present invention relates to a roll-shaped adhesive sheet for fixing a polishing pad, which is wound in a roll shape and has a length in the width direction of the wound body of 1000 mm or less, with a release sheet FA as described in any of [1] to [5] above.

[0014] [8] The present invention relates to a roll-shaped adhesive sheet for fixing a polishing pad, which is wound in a roll shape and has a length in the width direction of the wound body of 1000 mm or less, as described in [6], with a release sheet FA and a release sheet FB attached.

[0015] [9] The present invention relates to an adhesive sheet for fixing a polishing pad, with a release sheet FA and a release sheet FB as described in [6] above, having a short side length of 1000 mm or less.

[0016]

[10] The present invention is a polishing pad with an adhesive layer, comprising a polishing pad and an adhesive sheet for fixing a polishing pad with a release sheet FA as described in any one of [1] to [5] above, relating to a polishing pad with a release sheet FA and an adhesive layer A, where the polishing pad and the adhesive layer B are in contact.

[0017]

[11] A method for fixing a polishing pad to a surface plate via an adhesive sheet, characterized by peeling the release sheet FA from the polishing pad with the release sheet FA and the adhesive layer A as described in [9] above, and attaching the adhesive layer A to the surface plate.

[0018]

[12] A method for manufacturing an adhesive sheet for fixing a polishing pad with a release sheet FA and a release sheet FB, comprising a release sheet FA, an adhesive layer A, a sheet-like base material, an adhesive layer B, and a release sheet FB, having the following steps (1) to (4): (1) A step of applying an adhesive a to the surface of a release sheet FA having an average height Rc of irregularities on the peeled surface of 12 to 42 μm to form an adhesive layer A. (2) A step of overlapping a sheet-like base material on the surface of the adhesive layer A that is not in contact with the release sheet FA. (3) A step of applying an adhesive b to the peeled surface of a release sheet FB to form an adhesive layer B. (4) A step of overlapping the surface of the adhesive layer B that is not in contact with the release sheet FB on the surface of the sheet-like base material that is not in contact with the adhesive layer A. The surface of the adhesive layer A that is not in contact with the sheet-like base material has irregularities, and in a Bekk smoothness test, the smoothness of the said surface determined under the following condition 1 is 0.1 to 30 seconds, the smoothness of the said surface determined under the following condition 2 is 1 to 500 seconds, This invention relates to a method for manufacturing an adhesive sheet for fixing a polishing pad, which includes a release sheet FA and a release sheet FB. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: Time taken for the pressure to change from -50.7 kPa to -29.3 kPa.

[0019]

[13] A method for manufacturing an adhesive sheet for fixing an abrasive pad, comprising a release sheet FA, an adhesive layer A, a sheet-like substrate, an adhesive layer B, and a release sheet FB, The process involves the following steps (5) to (8): (5) A step of applying adhesive a to one side of a sheet-like substrate to form an adhesive layer A. (6) A step of placing the surface of a release sheet FA, which has an average height Rc of surface irregularities Rc of 12 to 42 μm, onto the surface of the adhesive layer A that is not in contact with the sheet-like substrate. (7) A step of applying adhesive b to the peeled surface of the release sheet FB to form an adhesive layer B. (8) A step of overlapping the surface of the adhesive layer B that is not in contact with the release sheet FB onto the surface of the sheet-like substrate that is not in contact with the adhesive layer A. The surface of adhesive layer A that is not in contact with the sheet-like substrate has irregularities, and in the Beck smoothness test, The surface smoothness determined by the following condition 1 is 1 to 30 seconds, The surface smoothness determined by the following condition 2 is 1 to 500 seconds. This invention relates to a method for manufacturing an adhesive sheet for fixing a polishing pad, which includes a release sheet FA and a release sheet FB. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: Time taken for the pressure to change from -50.7 kPa to -29.3 kPa.

[0020]

[14] A method for manufacturing an adhesive sheet for fixing an abrasive pad, comprising a release sheet FA, an adhesive layer A, a sheet-like substrate, an adhesive layer B, and a release sheet FB, the method comprising the following steps (9) to (12): (9) A step of applying adhesive b to the peeled surface of the release sheet FB to form an adhesive layer B. (10) A step of overlapping a sheet-like substrate onto the surface of the adhesive layer B that is not in contact with the release sheet FB. (11) A step of applying adhesive a to the surface of a release sheet FA having an average height Rc of surface irregularities Rc of 12 to 42 μm to form an adhesive layer A. (12) A step of overlapping the surface of the adhesive layer A that is not in contact with the release sheet FA onto the surface of the sheet-like substrate that is not in contact with the adhesive layer B. The surface of adhesive layer A that is not in contact with the sheet-like substrate has irregularities, and in the Beck smoothness test, The surface smoothness determined by the following condition 1 is 1 to 30 seconds, The surface smoothness determined by the following condition 2 is 1 to 500 seconds. This invention relates to a method for manufacturing an adhesive sheet for fixing a polishing pad, which includes a release sheet FA and a release sheet FB. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: Time taken for the pressure to change from -50.7 kPa to -29.3 kPa. [Effects of the Invention]

[0021] According to the present invention, a double-sided adhesive sheet for fixing a polishing pad to a surface plate can be provided that is easy to reposition, has excellent air release properties, and also has excellent adhesive properties and chemical resistance to strong alkalis and strong acids. The adhesive sheet for fixing a polishing pad with a release sheet FA of the present invention can improve workability during application and significantly improve polishing accuracy in high-precision CMP processing. [Brief explanation of the drawing]

[0022] [Figure 1] An embodiment of an adhesive sheet for fixing a polishing pad with a release sheet FA, and a schematic cross-sectional view showing its usage. [Figure 2] A schematic diagram illustrating the Beck smoothness test. [Figure 3] An illustrative diagram to explain the surface irregularities (cross-section) of the release sheet FA. [Figure 4] An illustrative diagram to explain the surface irregularities (cross-section) of the release liner. [Figure 5] An example image illustrating the surface irregularities on the outer side of the release sheet FA. [Figure 6] An illustrative diagram to explain the surface irregularities (plan view) on the outer side of the release sheet FA. [Figure 7] A schematic cross-sectional diagram showing an example of a method for manufacturing an adhesive sheet for fixing a polishing pad with a release sheet FA, and its usage. [Figure 8] A schematic diagram illustrating a method for evaluating the ease of bonding. [Figure 9] A schematic diagram illustrating the method for evaluating air leakage performance. [Modes for carrying out the invention]

[0023] The following describes an example of an embodiment to which the present invention is applied. In this specification, the numerical values ​​"A to B" refer to values ​​between A and B.

[0024] <Adhesive sheet for fixing polishing pads with release sheet FA> The adhesive sheet 1 for fixing polishing pads with a release sheet FA of the present invention, as shown in Figure 1-1, is provided on an adhesive sheet 0 for fixing polishing pads (hereinafter also referred to as "adhesive sheet") which has adhesive layers A and B on both sides of a sheet-like substrate F, and the release surface of the release sheet FA is in contact with and covered to protect the surface of adhesive layer A (the side not in contact with the sheet-like substrate F). In the configuration shown in Figure 1-1, as shown in Figure 1-1', the adhesive sheet 1 for fixing polishing pads with a release sheet FA is wrapped around a cylindrical member called a core (also called a core material), and the surface of adhesive layer B is covered with the other side of the release sheet FA (the side not in contact with adhesive layer A), and it is also possible to provide it in a roll-like form. Note that in Figure 1, the surface irregularities of the release sheet FA and adhesive layer A are not shown. The adhesive sheet 1 for fixing the polishing pad with a release sheet FA can also be provided in the form of an adhesive sheet 2 for fixing the polishing pad with a release sheet FA and a release sheet FB, as shown in Figure 1-2, which includes a release sheet FB covering the surface of the adhesive layer B. As shown in Figure 1-3, the adhesive layer B of the adhesive sheet 1 for fixing the polishing pad with a release sheet FA is laminated with the polishing pad PP to form the polishing pad 3 with a release sheet FA. Next, as shown in Figure 1-4, the release sheet FA is peeled off, and the polishing pad 4 with the adhesive layer A exposed is attached to the surface plate SP. Adhesive layer A of the adhesive sheet 0 is in contact with the surface plate, and adhesive layer B is in contact with the polishing pad. In other words, the polishing pad PP is fixed to the surface plate SP via the adhesive sheet 0, which has a laminated structure of adhesive layer A / sheet-like substrate F / adhesive layer B.

[0025] When attaching the polishing pad PP to the surface plate via the adhesive sheet 0, in most cases until now, the surface of the polishing pad PP has been slowly rubbed from the edge with a roll or squeegee while slightly bending and flexing the pad PP, pushing out the air from the edge as it is attached. When attaching the adhesive layer A to the surface plate, if the adhesive sheet wrinkles or uneven force is applied to the adhesive sheet, a large localized air pocket will occur between the surface plate SP and the adhesive layer A. By the way, recently, polishing pads made of PP (polypropylene) tend to become increasingly thicker, extremely hard, or extremely soft. Polishing pads made of PP that have become thicker or extremely hard are too rigid and cannot be bent as conventionally, making it difficult to apply sufficient pressure to the surface of the polishing pad using tools such as rolling rollers or squeegees. On the other hand, extremely softened PP polishing pads are prone to bending and flexing, making it difficult to maintain a flexible state when working the surface of the polishing pad with a roll or squeegee. In either case, it is not possible to quickly push out the air at the bonding interface or to smooth the entire interface, resulting in the tendency for large localized air pockets to remain. Furthermore, when the surface of the polishing pad PP is rubbed with a roll or squeegee, localized pressure is applied to the surface of the polishing pad PP. Although the pressure is applied sequentially across the entire surface of the polishing pad, there is a requirement to avoid applying too much force to the surface of the polishing pad PP, as it is the surface that will come into contact with the object to be polished.

[0026] In the adhesive sheet for fixing a polishing pad with a release sheet FA of the present invention, the outer surface of the release sheet FA has irregularities as identified by a Beck smoothness test. Irregularities equivalent to these irregularities become the surface irregularities of the adhesive layer A that was in contact with the release sheet FA. The surface of the adhesive layer A is the surface that is to be in contact with the surface plate SP. The adhesive layer A has irregularities similar to those of the outer surface of the release sheet FA transferred to it, and the recesses on the surface of the adhesive layer A can be used as ventilation paths (flow channels) to push air between the surface plate SP and the adhesive layer A outwards from the surroundings or to smooth the entire adhesive interface. As a result, the occurrence of large localized air pockets between the surface plate and the adhesive sheet that would impair the parallelism between the surface of the polishing pad (the surface in contact with the object to be polished) and the surface plate can be suppressed and prevented.

[0027] This section describes the Beck smoothness of the outer surface of the release sheet FA. The Beck smoothness is specified in JIS P8119. This section outlines the procedure for the Beck smoothness test. (1) Place the test specimen on the flat surface of a glass that has been optically planarized (a ring-shaped glass component with a circular hole in the center that connects to a vacuum container). (2) With a pressure of 0.1 MPa applied to the rubber retaining plate placed on the test specimen via a pressure plate, the pressure inside the vacuum chamber is reduced to -50.7 kPa. (3) Once the pressure reaches -50.7kPa, stop reducing the pressure and allow atmospheric air to be drawn in between the glass plane and the contact surface of the test specimen. Measure the time it takes for the pressure inside the vacuum chamber to change from -50.7kPa to -48.0kPa (condition 1) and from -50.7kPa to -29.3kPa (condition 2). The permeability of the surface of adhesive layer A can be evaluated based on these values. In other words, in both conditions 1 and 2, the shorter the time it takes to return to the predetermined pressure, the more permeable the surface is.

[0028] In the present invention, as shown in Figure 2(a), a polyethylene terephthalate (PET) film with a thickness of 100 μm and an Rc of less than 0.5 μm on both sides is attached to the adhesive layer B of the adhesive sheet, then cut to a 50 mm square, stack two sheets together, and make a circular hole with a radius of 5 mm (smaller than the circular hole in the center of the glass member) to prepare the measurement sample. As shown in Figure 2(b), the outer surface of the bottom release sheet FA is placed on the surface of the glass member so that the hole in the measurement sample is directly above the circular hole in the center of the glass member, a rubber press plate is placed on the top surface of the top PET film, and a pressure of 0.1 MPa is applied via a pressure plate, and the pressure is reduced by suction from below the circular hole in the center of the glass member to determine the smoothness under conditions 1 and 2. Since the measurement sample consists of two adhesive sheets stacked together, half of the measured value represents the result for adhesive layer A per adhesive sheet. In other words, if the measured value is 2 seconds, the Beck smoothness of the outer surface of the release sheet FA will be 1 second.

[0029] Under Condition 1, the Beck smoothness of the outer surface of the release sheet FA is important to be 0.1 to 30 seconds, more preferably 0.2 to 15 seconds, particularly preferably 0.3 to 5 seconds, and most preferably 0.5 to 4 seconds. The smoothness of Condition 1 relates to the movement and state of air in the very initial stages when the adhesive layer A contacts the surface plate, and is mainly related to position adjustment. Specifically, if the smoothness of Condition 1 is 30 seconds or less, localized large air pockets are less likely to occur when the adhesive layer A contacts the surface plate, and the adhesive layer A can adhere tightly to the surface plate as if being sucked in. When the position of the adhesive layer A in contact with the surface plate is appropriate and no position adjustment is necessary, if the smoothness of Condition 1 is less than 0.1 seconds, the airflow is too good, and the position of the adhesive layer A is more likely to shift. In other words, if the smoothness of Condition 1 is 0.1 seconds or more, it becomes easier to maintain the position of the abrasive sheet that has been sucked into the surface plate.

[0030] Furthermore, under condition 2, the Beck smoothness of the outer surface of the release sheet FA is important to be 1 to 500 seconds, preferably 2 to 300 seconds, more preferably 5 to 200 seconds, even more preferably 6 to 100 seconds, and most preferably 9 to 50 seconds. The smoothness of Condition 2 relates to the movement and state of air during the period from a few minutes to about ten minutes after the adhesive layer A is attached to the surface plate, and is mainly related to the air release properties of the adhesive interface. If the smoothness of Condition 2 is 500 seconds or less, even if localized air pockets occur between the surface plate and the adhesive layer A, it becomes easier to spread the air evenly across the entire adhesive interface through the recesses of the adhesive interface, or to release air from the outer periphery. If the smoothness of Condition 2 is 1 second or more, the adhesive layer A in contact with the surface plate adheres more firmly to the surface plate.

[0031] Furthermore, the surfaces of the release sheet FB and the adhesive layer B (the surfaces that will come into contact with the polishing pad) do not need to have any special irregularities. When attaching the polishing pad 3 to the surface plate SP, the attachment is done manually, which makes it easy for large localized air pockets to form between the adhesive layer A and the surface plate SP. On the other hand, when attaching the polishing pad PP to the adhesive layer B of the polishing pad fixing adhesive sheet 1 with a release sheet FA, the attachment is done mechanically rather than manually, so unlike when attaching the polishing pad 3 to the surface plate SP, large localized air pockets are unlikely to form in the first place.

[0032] This section describes the shape of the surface irregularities (cross-section) of the release sheet FA. Note that the adhesive layer A has a pattern transferred to it that is an inverted version of the pattern on the outside of the release sheet FA, so it has the same shape as the outside surface of the release sheet FA. In the diagram, the upper part of the cross-section is in contact with the adhesive layer A, and the lower part is the outside of the release sheet FA. For the sake of explanation, the side of the release sheet FA that is in contact with the adhesive layer A will be referred to as the inside of the release sheet FA, and the side that is not in contact will be referred to as the outside of the release sheet FA. From the standpoint of improving alignment, it is preferable that the area near the top of the protrusion is gently rounded, as shown in Figure 3-1, rather than flat, as shown in Figure 3-2. Also, from the standpoint of improving the air release properties of the adhesive tape, Figure 3-1, in which the recess on the outside of the release sheet FA is wider (i.e., the recess of the adhesive layer A is wider), is preferable to Figure 3-2. Figure 3-3 has a wider recess on the outside of the release sheet FA than Figure 3-2, so some improvement in air release properties can be expected in that respect. However, the wider recess on the outside of the release sheet FA may reduce the polishing accuracy.

[0033] Therefore, in order to improve alignment and air release without reducing polishing accuracy, the average height Rc (hereinafter abbreviated as average height Rc) of the roughness curve elements on the outer surface of the release sheet FA is preferably 12 to 42 μm, more preferably 17 to 37 μm, and even more preferably 22 to 32 μm. Being within this range allows the uneven surface to be reversed and transferred to the adhesive layer A with high accuracy. Since the average height Rc of the outer surface of the release sheet FA is 12 μm or more, the recesses become relatively deeper, so the air permeability is improved on the surface of the adhesive layer A in both conditions 1 and 2 of the Beck smoothness test, improving alignment and air release. In particular, the effect on air release is significant, making it easier to peel the polishing pad and adhesive sheet off the surface plate after polishing is complete. Because the average height Rc of the outer surface of the release sheet FA is 42 μm or less, when the adhesive layer A, which has such an average height Rc reversed and transferred, is attached to a surface plate as a polishing pad and polished, the uneven shape does not easily affect the outermost surface of the polishing pad that comes into contact with the workpiece, resulting in superior polishing accuracy.

[0034] The shape of the unevenness on the outer surface of the release sheet FA of the present invention can be more specifically understood from two parameters: the difference in cutting levels of the contour curve: Rδc and the crustosis: Rku, which allows for a more concrete understanding of the shape of the unevenness, such as the roundness and slope of the protrusions and the spacing of the unevenness. Rδc is preferably 5 to 25 μm, more preferably 10 to 20 μm, and even more preferably 12.5 to 19.0 μm. Rδc is the difference in height levels that matches any two load length ratios from the load curve (a curve plotting the ratio of the actual body length to the measured length in order of height), and in this invention, the two load length ratios are defined as 0% and 50%. Because Rδc is 5 μm or more, air pockets are less likely to form in the very early stages of application, and the tops of the protrusions of the adhesive layer A formed on the inside of the release sheet FA make loose (light) contact with the surface plate. In other words, since the adhesive layer does not adhere very strongly to the surface plate, when peeling off the adhesive layer A from the surface plate after contact, it can be peeled off with little resistance, making position adjustment easier. Incidentally, because adhesive layer A is adhesive, it is thought that it will deform to some extent when it is attached to the surface plate. In other words, microscopically, it is imagined that the convex parts on the surface of adhesive layer A will be compressed to a small degree during attachment, and the concave parts will become relatively shallower. Since Rδc is 25 μm or less, when adhesive layer A is firmly attached to the surface plate, adhesive layer A will not be easily crushed, the depth of the concave parts will be maintained, and air release will be improved.

[0035] Furthermore, it is preferable that the kurtosis (Rku) of the outer surface of the release sheet FA be less than 3. An Rku of less than 3 indicates a rounded convex shape. By bringing the rounded top of the convex part into contact with the surface plate during application, positioning can be performed with a feeling of suction. It is particularly preferable that the Rku is in the range of 1.5 to less than 3, as this improves workability during positioning and provides strong adhesion when pressed firmly to fix it in place, thus suppressing problems such as peeling off during polishing.

[0036] Rc, Rδc, and Rku will be explained using schematic diagrams. Figures 3-1, 3-4, and 3-5 show cases where Rc is approximately the same. If Figure 3-1 shows the case where Rδc is 5 to 25 μm and Rku is less than 3, then in Figure 3-4, where the slope of the convex part is steeper than in Figure 3-1, Rδc is larger than in Figure 3-1, and Rku is less than 3. Similarly, in Figure 3-5, where the slope of the convex part is steeper than in Figure 3-1, Rδc is larger than in Figure 3-1, and because the top of the convex part is pointed, Rku is greater than 3. Furthermore, Figures 3-6 and 3-7 also illustrate the case where Rc is approximately the same as in Figure 3-1, but because the spacing between the bumps and depressions is wider than in Figure 3-1, Rδc becomes smaller than in Figure 3-1, Rku becomes 3 smaller in Figure 3-6, and Rku becomes greater than 3 in Figure 3-7.

[0037] Rc, Rδc, and Rku are values ​​measured according to JIS B 0601 (2013), and can be measured using a laser microscope (Keyence VK-X100). Specifically, at a magnification of 400x, five consecutive images are taken in both the vertical and horizontal directions (25 images in total) of a field of view of approximately 460 μm vertically and 640 μm horizontally, and the entire observation field is approximately 2300 μm vertically and 3200 μm horizontally. The measurement field is the central area of ​​the entire observation field, approximately 1840 μm vertically and 2560 μm horizontally, and Rc, Rδc, and Rku are measured along the two diagonals of the measurement field, and the average value of each is calculated. The same applies to the measurement of Rc, etc., of the release sheet FA, which will be described later.

[0038] Figure 4-1 shows an image of the surface irregularities on the outer side of the release sheet FA in the present invention, and Figure 4-2 shows an image of the surface irregularities of a so-called "matte" surface. Unlike the surface irregularities of a so-called "matte" surface intended for optical matting, the surface irregularities on the outer side of the release sheet FA in the present invention are large and rough. Because the irregularities of a "matte" surface are small, it is difficult to transfer the surface irregularities of the outer side of the release sheet FA directly to the adhesive layer A. Even if it were transferred to the adhesive layer A, the Rc, Rδc, and Rku of the present invention form on the adhesive layer A, and because the height difference of the irregularities is larger and the spacing of the irregularities is wider than that of a so-called "matte" surface which is good at general optical matting, it represents an ideal shape for initial position adjustment during application, air release during application, and fixing the polishing pad to the surface plate parallel and smoothly.

[0039] This section describes the surface irregularities (plan view) on the outer side of the release sheet FA. The surface irregularities (in plan view) on the outer surface of the release sheet FA in the present invention may be regular patterns such as grid patterns or polka dot patterns, but it is preferable that they be irregular and irregular in shape as shown below. Figure 5 shows an example of an image of the outer surface of the release sheet FA observed with a laser microscope. In the upper part of Figure 5, the black areas are convex, and they are irregular and irregular in shape when viewed from above. Examples of irregular and irregular patterns and designs in the present invention include those shown in Figures 6(1) to (4). Figure 6(1) is sometimes called a sandy texture, leather texture, rock texture, stone texture, or plain surface. Figure 6(2) is a type of uneven pattern or design called mottling in the field of inks and paints. Figure 6(3) is also called mottling, but it is a pattern or design that can be seen on decorative stickers for plastic models. Figure 6(4) is sometimes called a Dalmatian pattern. In the patterns and designs shown in Figures 6(1) to (4), there is no regularity in the position of both the raised parts (black parts) and recessed parts (white parts), and no regularity is observed in their shape either.

[0040] In the adhesive sheet for fixing polishing pads with a release sheet FA, if the Beck smoothness of the outer surface of the release sheet FA is within the above range under conditions 1 and 2, there is no difference in terms of position adjustment and air release when attaching to the surface plate, regardless of whether the shape of the unevenness in plan view is irregular and irregular or regular and regular. However, if the pattern / design in plan view is irregular and irregular, it is easier to mitigate uneven force during attachment and to attach uniformly. Furthermore, even if scratches occur on the outer surface of the release sheet FA or unevenness occurs on the surface of the adhesive layer A to an extent that does not affect performance, it is preferable if the pattern / design in plan view is irregular and irregular because it is less noticeable.

[0041] One method for obtaining an adhesive sheet for fixing a polishing pad with a release sheet FA having a Beck smoothness within a predetermined range is to use a release sheet FA having irregularities on its surface with an average height Rc of 12 to 42 μm. Specifically, a release sheet FA' having a release layer is prepared, and then, as shown in Figure 7-1, the release sheet FA' is passed at high temperature between a metal roll R1 and a rubber roll R2 that have been processed to a desired surface shape, thereby inverting and transferring the surface shape of the metal roll R1 and producing a release sheet FA with irregularities having an average height Rc of 12 to 42 μm. Note that when the surface shape of the release sheet FA is inverted and transferred by the rotation of the metal roll R1, the surface shape will have a certain periodicity, but this periodicity is different from the regularity in the plan view described above. Incidentally, when measuring the Beck smoothness of an adhesive sheet with a release sheet FA, which has such irregularities, the irregularities on the outer surface of the release sheet FA deform (collapse) due to the pressure applied during measurement. The deformation of the irregularities on the outer surface of the release sheet FA is affected by the thickness and hardness of the adhesive layer FA in contact with the inner surface of the release sheet FA. For example, for adhesive layers of the same type, the thicker the layer, the easier it is for stress to relax, so the irregularities on the outer surface of the release sheet FA collapse to become smoother, and the Beck smoothness value of the adhesive sheet with the release sheet increases. The Beck smoothness of an adhesive sheet with a release sheet FA is a value that takes into account the deformation of the irregularities on the outer surface of the release sheet FA and the deformation of the irregularities of the adhesive layer FA in contact with the inner surface of the release sheet FA due to pressure. Therefore, the Beck smoothness value of an adhesive sheet with a release sheet is related to the ease of application and air release when attaching the adhesive layer A to a surface plate, the adhesive strength and holding power to the surface plate, and the polishing accuracy.

[0042] and, (1) The adhesive layer A is formed by applying adhesive a onto the release layer of the release sheet FA and drying it as needed. (2) A sheet-like substrate is placed on the surface of the adhesive layer A that is not in contact with the release sheet FA. (3) Apply adhesive b to the peeled surface of the release sheet FB and dry as necessary to form adhesive layer B. (4) The surface of the adhesive layer B that is not in contact with the release sheet FB is placed on top of the surface of the sheet-like substrate that is not in contact with the adhesive layer A. As a result, an adhesive sheet for fixing polishing pads with a release sheet can be manufactured, having a laminated structure of [release sheet FA / adhesive layer A / sheet-like substrate F / adhesive layer B / release sheet FB] as shown in Figure 7-2.

[0043] or, (5) Apply adhesive a to one side of the sheet-like substrate and dry as necessary to form an adhesive layer A. (6) The surface of the release sheet FA, which has an average height Rc of surface irregularities Rc of 12 to 42 μm, is superimposed on the surface of the adhesive layer A that is not in contact with the sheet-like substrate. (7) The adhesive b is applied to the peeled surface of the release sheet FB and dried as necessary to form the adhesive layer B. (8) The surface of the adhesive layer B that is not in contact with the release sheet FB is placed on top of the surface of the sheet-like substrate that is not in contact with the adhesive layer A. Even with this method, it is possible to produce an adhesive sheet for fixing polishing pads with a release sheet, having a laminated structure of [release sheet FA / adhesive layer A / sheet-like substrate F / adhesive layer B / release sheet FB] as shown in Figure 7-2.

[0044] or, (9) The adhesive b is applied to the peeled surface of the release sheet FB and dried as necessary to form the adhesive layer B. (10) A sheet-like substrate is placed on the surface of the adhesive layer B that is not in contact with the release sheet FB. (11) The surface of the release sheet FA, which has an average height Rc of surface irregularities Rc of 12 to 42 μm, is coated with adhesive a and dried as necessary to form an adhesive layer A. (12) The surface of the adhesive layer A that is not in contact with the release sheet FA is placed on top of the surface of the sheet-like substrate that is not in contact with the adhesive layer B. Even with this method, it is possible to produce an adhesive sheet for fixing polishing pads with a release sheet, having a laminated structure of [release sheet FA / adhesive layer A / sheet-like substrate F / adhesive layer B / release sheet FB] as shown in Figure 7-2. In all cases, it is preferable that the surface of the adhesive layer B (the surface that will come into contact with the polishing pad) is smooth, so it is preferable that the release surface of the release sheet FB to which the adhesive b is applied is smooth.

[0045] For coating the adhesive, known methods such as the roll coater method, comma coater method, lip coater method, die coater method, reverse coater method, silkscreen method, and gravure coater method can be used. After coating, it can be dried using a hot air oven, infrared heater, or the like.

[0046] By removing the release sheet FB from the adhesive sheet for fixing the polishing pad, which has a laminated structure of [release sheet FA / adhesive layer A / sheet-like substrate F / adhesive layer B / release sheet FB] obtained by various methods, and attaching the polishing pad PP to the exposed adhesive layer B as shown in Figure 7-3, a polishing pad 4 with a laminated structure of [release sheet FA / adhesive layer A / sheet-like substrate F / adhesive layer B / polishing pad PP] can be obtained. Next, by peeling off the release sheet FA that covered the adhesive layer A from the resulting release sheet and the adhesive-layered polishing pad 4, a polishing pad 3 is obtained that has an adhesive layer A with the uneven surface of the release sheet FA reversed and transferred onto it. Then, as shown in Figure 7-4, the polishing pad PP can be fixed to the surface plate SP via the adhesive sheet by attaching the exposed adhesive layer A to the surface plate SP.

[0047] <Adhesive layer> In the adhesive sheet for fixing polishing pads of the present invention, adhesive layers A and B are located on the outermost surfaces of the adhesive sheet, respectively. The sheet-like substrate may be a single layer or a laminate of various materials, and the number of layers is not particularly limited. The thickness of the adhesive layer A of the adhesive sheet for fixing the polishing pad is preferably 15 to 100 μm, and more preferably 30 to 70 μm. A thickness of 15 μm or more of adhesive layer A makes it easier to exhibit adhesive strength. However, the thicker the layer, the more easily the irregularities of the adhesive layer A formed by the use of the release sheet FA are crushed, resulting in poor breathability when attached to the surface plate. Therefore, a thickness of 100 μm or less makes it easier to maintain the irregular shape required by the present invention even under pressure during the polishing process. Being within the more preferable range provides excellent adhesiveness and suppresses the problem of the adhesive layer shifting in the shear direction when the adhesive sheet becomes hot during polishing. The thickness is the average value measured at 5 arbitrary points using a Mitutoyo Lightmatic VL-50B thickness gauge with a Φ7.5 mm probe pressed with a pressure of 0.01 N. The thickness of adhesive layer B is not particularly limited as long as various polishing pads can be fixed to it. However, by making the combined thickness of adhesive layer B (excluding the thickness of the base layer) and adhesive layer A 200 μm or less, the proportion of the adhesive layer, which is a low-elastic material, in the entire adhesive sheet is reduced, and the polishing accuracy is improved.

[0048] The adhesive layers A and B of the adhesive sheet of the present invention can use acrylic adhesives, elastomer adhesives, urethane adhesives, silicone adhesives, etc., and two or more may be used in combination. Acrylic adhesives are preferred from the viewpoint of less gel generation, less local difference in elastic modulus, and easy control of adhesive strength. While elastomer-based and urethane-based adhesives often use metal catalysts during synthesis, and silicone-based adhesives often use metal catalysts during curing, acrylic-based adhesives are preferable because they contain less metal catalyst, thus having less impact on CMP processing and offering high chemical resistance. Furthermore, in order to accommodate a wide variety of polishing pad materials, it is preferable to select an acrylic adhesive with a rich variety of monomer species for the adhesive layer B.

[0049] <Acrylic adhesive> The acrylic adhesive contains an acrylic copolymer and a curing agent. It may also contain a tackifying resin. The acrylic copolymer preferably has carboxyl groups or hydroxyl groups, and more preferably is a (meth)acrylate resin having hydroxyl groups.

[0050] <(meth)acrylate resin> The (meth)acrylate resin is obtained by copolymerizing a monomer having a hydroxyl group with another monomer that does not have a hydroxyl group. That is, the (meth)acrylate resin is a copolymer consisting of units derived from a monomer having a hydroxyl group and units derived from another monomer.

[0051] Examples of monomers having a hydroxyl group include hydroxyalkyl (meth)acrylates and compounds obtained by adding ε-caprolactone to the hydroxyalkyl (meth)acrylate, with hydroxyalkyl (meth)acrylates being preferred.

[0052] Specific examples of hydroxyalkyl (meth)acrylates include hydroxyalkyl (meth)acrylates with 1 to 4 carbon atoms in the alkyl group, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Specific examples of compounds obtained by adding ε-caprolactone to hydroxyalkyl (meth)acrylates include ε-caprolactone adducts of hydroxyalkyl (meth)acrylates with 1 to 4 carbon atoms, such as a 1-mol ε-caprolactone adduct of 2-hydroxyethyl (meth)acrylate, a 2-mol ε-caprolactone adduct of 2-hydroxyethyl (meth)acrylate, and a 3-mol ε-caprolactone adduct of 2-hydroxyethyl (meth)acrylate. However, the present invention is not limited to these examples. These hydroxyl group-containing monomers may be used individually or in combination. 2-hydroxyethyl (meth)acrylate is particularly preferred because, when crosslinked with an isocyanate curing agent, the intermolecular distances are relatively close, resulting in improved chemical resistance.

[0053] Other monomers that do not have a hydroxyl group include a variety of monomers such as those listed below. Examples of alkyl (meth)acrylates include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, isoamyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and tert-butylhexyl (meth)acrylate, as well as 2-acetoacetoxyethyl (meth)acrylate and phenoxyethyl (meth)acrylate.

[0054] The weight-average molecular weight (Mw) of the acrylic copolymer is preferably 200,000 to 1,800,000, and more preferably 500,000 to 1,500,000. A weight-average molecular weight (Mw) of 200,000 or more makes it easier for the adhesive to obtain cohesive force that can withstand strong shear forces, while a weight-average molecular weight (Mw) of 1,800,000 or less provides excellent heat resistance and prevents a decrease in adhesion to abrasive materials, thus improving performance.

[0055] Methods for polymerizing monomers include, for example, solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization, but the present invention is not limited to such polymerization methods. Among these polymerization methods, solution polymerization is preferred because the resulting reaction mixture can be used as is.

[0056] <Elastomer-based adhesive> The elastomer-based adhesive contains an elastomer and a tackifying resin. The elastomer preferably contains a styrene-isoprene block copolymer.

[0057] Styrene isoprene block copolymers exist with either a linear or radial structure. However, the linear structure offers greater flexibility, resulting in superior adhesion to various substrates and better tackiness and heat resistance. Therefore, a linear structure consisting of a triblock (SIS) of styrene blocks and a diblock (SI) of styrene-isoprene is preferable. A linear styrene isoprene block copolymer refers to a linear copolymer in which styrene blocks and isoprene blocks are bonded together.

[0058] The styrene-isoprene block copolymer preferably has a styrene content of 20 to 40% by weight per 100% by weight. The diblock content is preferably 15 to 70% by weight. When the styrene content and diblock content are within the above ranges, it can have excellent adhesive properties with strong cohesive force, and its holding power and chemical resistance after being in a high-humidity environment are improved.

[0059] Examples of styrene-isoprene block copolymers include, but are not limited to, Kraton D1119 (manufactured by Kraton, styrene content 22% by weight, diblock content 66% by weight), Kraton D1126 (manufactured by Kraton, styrene content 21% by weight, diblock content 30% by weight), and Kraton D1117 (manufactured by Kraton, styrene content 17% by weight, diblock content 33% by weight). Two or more types may be used in combination as needed.

[0060] Furthermore, natural rubber may be included, provided that it does not impair the required performance. While there are no particular limitations on the natural rubber, it is preferable to knead it using a kneading roll and achieve a Mooney viscosity of, for example, 10 to 100. Other elastomers and natural rubbers are not limited to these, and one or more types can be used in combination.

[0061] <Silicone-based adhesive> Silicone-based adhesives can use materials known as silicone resins. Specifically, organopolysiloxanes having silanol groups at both ends of the molecular chain, with R3SiO in the molecule. 0.5 Examples include those obtained by partial dehydration condensation of organopolysiloxanes having triorganosiloxane units and SiO2 units, represented by (where R represents a substituted or unsubstituted monovalent hydrocarbon group). These are available as silicone adhesives KR-101-10, KR-120, KR-130, and X-40-3068 (all manufactured by Shin-Etsu Chemical Co., Ltd.). There are generally two curing methods for silicone adhesives: a curing method using peroxides such as benzoyl peroxide, and a curing method utilizing the reaction of a platinum catalyst with an organopolysiloxane having Si-H bonds. Either method can be used, and they can also be used in combination.

[0062] <Adhesive-granting resin> Examples of tackifying resins include rosin-based resins such as rosin esters, polymerized rosin, hydrogenated rosin, disproportionated rosin, maleic acid-modified rosin, fumaric acid-modified rosin, and rosinphenol resins; terpene-based resins such as α-pinene resin, β-pinene resin, dipentene resin, aromatically modified terpene resin, hydrogenated terpene resin, terpenephenol resin, acid-modified terpene resin, and styrene-modified terpene resin; alkylphenol resin, coumarone-based resin, styrene-based resin, petroleum-based resin, or copolymers thereof, with terpenephenol resin being particularly preferred. The above tackifying resins can be used individually or in combination of two or more.

[0063] <Hardening agent> A hardening agent can be added to the adhesive as needed. Since the required peeling force when removing the adhesive from the polishing machine platen varies from high to low adhesive strength, a hardening agent can be added to control the adhesive strength. As long as the desired performance is not compromised, isocyanate-based hardening agents, aziridine-based hardening agents, metal chelate-based hardening agents, and epoxy-based hardening agents can be used as needed. In particular, for acrylic adhesives, isocyanate-based hardening agents are preferred from the viewpoint of cohesive strength and heat resistance. These hardening agents may be used individually or in combination of two or more types.

[0064] <Other additives> The various adhesives used to form the adhesive layer in the adhesive sheet of the present invention may include, as necessary, various additives such as antioxidants and other known anti-aging agents, fillers, pigments, dyes, diluents, plasticizers, polymerization inhibitors, UV absorbers, UV stabilizers, coupling agents, etc., and two or more types of additives may be used. Furthermore, the amount of additives added is not particularly limited, as long as it is sufficient to obtain the required physical properties.

[0065] <Release Sheet FA>, <Release Sheet FB> Release sheets FA and FB have a release layer formed by coating a release agent onto a sheet-like substrate such as paper, plastic film, or synthetic paper. In CMP processing, release sheets made from highly clean plastic film as the sheet-like substrate are preferred. For the plastic film used for release sheets FA, polyethylene terephthalate film is preferred because it is inexpensive and easy to emboss with a metal roll. Furthermore, compared to cutting or laser processing, embossing with a metal roll is preferable because it is less prone to foreign matter contamination and results in a product with superior cleanliness. In addition, for the embossing with a metal roll as exemplified, it is preferable to use a release sheet with a thickness of 25 to 100 μm, and more preferably 45 μm to 80 μm. With this range, it is easy to transfer the same shape as the desired shape formed on the metal surface to the release sheet (transferability), the outside and inside of the release sheet FA become the same shape but inverted (reversibility), and the pattern on the surface of the adhesive layer A formed by coating the inside of the release sheet FA becomes the shape of the inside of the release sheet FA. Through this series of processing steps, the embossed pattern of the metal roll can be reproducibly transferred to the surface of the adhesive layer A. From the standpoint of transferring the uneven surface of the release sheet FA onto the surface of the adhesive layer A, the average height Rc of the release sheet FA is preferably 12 to 42 μm, more preferably 17 to 37 μm, and even more preferably 22 to 32 μm. Being within this preferred range allows for highly accurate transfer of the uneven surface onto the adhesive layer A.

[0066] For the release sheet FB, an inexpensive and highly smooth polyethylene terephthalate film is preferred as the plastic film. While there are no particular restrictions on the thickness of the release sheet FB, a thickness of 10-200 μm is preferred as it provides the film with sufficient rigidity and makes it easier to peel off. Examples of release agents used in release sheets FA and FB include silicone resins, alkyd resins, melamine resins, fluororesins, and acrylic resins, with silicone resins being preferred.

[0067] <Sheet-like substrate> The sheet-like substrate of the present invention is preferably a nonwoven fabric or a plastic film. Examples of plastic films include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, PPS (polyphenylene sulfide), nylon, triacetylcellulose, cycloolefin, polyimide, and polyamide. In particular, polyethylene terephthalate films are preferred due to their low manufacturing cost, excellent chemical resistance, and smoothness.

[0068] The thickness of the sheet-like substrate is not particularly limited, but is preferably 5 to 200 μm, more preferably 25 to 75 μm, and especially preferably 50 to 75 μm. Being within this preferred range ensures that the irregularities of adhesive layer A do not affect adhesive layer B or the polishing pad, providing appropriate stiffness and improving workability during application. Being within this particularly preferred range further improves workability.

[0069] The sheet-like substrate in the present invention may be subjected to an easy-adhesion treatment to improve the adhesion between adhesive layer A and adhesive layer B. The easy-adhesion treatment can be performed using known methods such as a dry method involving corona discharge and a wet method involving coating with an anchor coating agent. When using an acrylic adhesive to form the adhesive layer, it is preferable to use one that has been treated for easy adhesion to improve adhesion. On the other hand, in the case of elastomer adhesives, if the material has been treated for easy adhesion by corona discharge, the adhesive layer tends to peel off the sheet-like substrate more easily. Therefore, it is preferable to apply the elastomer adhesive to a surface that has not been treated for easy adhesion.

[0070] The thickness of the adhesive sheet for fixing the polishing pad, which consists of adhesive layer A, a sheet-like substrate, and adhesive layer B, is preferably 80 to 300 μm, and more preferably 100 to 200 μm. A thickness of 80 μm or more allows for uniform processing without uneven force distribution during lamination when integrating with the polishing pad, while a thickness of 300 μm or less allows for the adhesive sheet to be manufactured in a roll shape, increasing productivity. A thickness within the more preferable range ensures that the force from the polishing plate is properly transmitted to the polishing pad during polishing, improving polishing accuracy.

[0071] <Usage form> An example of how the adhesive sheet for fixing polishing pads of the present invention can be used is described below. As shown in Figures 1-2 and 7-2, the adhesive sheet for fixing the polishing pad can be provided with a release sheet FA, where each side of the adhesive sheet for fixing the polishing pad is covered with release sheets FA and FB, respectively. Alternatively, as shown in Figure 1-3, the adhesive sheet for fixing the polishing pad can be provided with only the adhesive layer A side covered with release sheet FA. In the configuration shown in Figure 1-3, as shown in Figure 1-3', the adhesive sheet 2 for fixing the polishing pad with release sheet FA is wrapped around a cylindrical member called a core (also called a core material), and the surface of the adhesive layer B is covered with another side of the release sheet FA (the side not in contact with the adhesive layer A), thereby providing a roll-shaped adhesive sheet for fixing the polishing pad with release sheet FA.

[0072] As shown in Figures 1-4 and 7-3, the polishing pad is laminated onto the surface of the adhesive layer B of the adhesive sheet for fixing the polishing pad with a release sheet FA, thereby forming the polishing pad 3 with the release sheet FA and adhesive layer A. Next, as shown in Figures 1-4 and 7-4, the release sheet FA is peeled off to expose the adhesive layer A, and the polishing pad 3 with adhesive layer A is attached to the surface plate SP. Adhesive layer A of the adhesive sheet 0 for fixing the polishing pad is in contact with the surface plate, and adhesive layer B is in contact with the polishing pad.

[0073] A polishing pad, also known as a polishing cloth, polishing pad, or polishing PAD, is a component that comes into contact with the surface of the object to be polished and polishes it. Polishing pads come in two types: single-layer types made of a single material and multi-layer types made of multiple layers. The outermost surface material of a polishing pad can be made of urethane, non-woven fabric, or suede. In the case of multi-layer types, urethane foam, polyethylene foam, or polypropylene foam are used as cushioning materials in the inner layers. [Examples]

[0074] The present invention will be described more specifically below with reference to examples, but the present invention is not limited to the following examples. In the examples, "parts" means "parts by weight" and "%" means "percent by weight".

[0075] [Molecular weight] In the following examples, molecular weight is the weight-average molecular weight in polystyrene equivalent, measured by GPC (gel permeation chromatography). The measurement device used was a GPC-8020 (Tosoh Corporation), with tetrahydrofuran as the eluent, and three TSKgelSuperHM-M columns (Tosoh Corporation). The measurement was performed at a column temperature of 40°C, a flow rate of 0.6 mL / min, a sample concentration of 0.3%, and an injection volume of 10 μL.

[0076] [Non-volatile content] Non-volatile content refers to the value calculated by dividing the mass of the sample after heating by the mass of the sample before heating, when 1 g of the sample is heated at 170°C for 10 minutes. However, in the case of commercially available products, the value calculated according to the method specified by the manufacturer may be used.

[0077] (Adhesive) <Manufacturing of acrylic adhesive (P-1) solution> In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, and thermometer, 500 g of ethyl acetate was heated in a water bath while introducing nitrogen gas. Subsequently, a mixture of 360 g of BA (n-butyl acrylate), 120 g of 2-EHA (2-ethylhexyl acrylate), 10 g of AA (acrylic acid), 5 g of HEA (hydroxyethyl acrylate), and 0.5 g of AIBN (azobisisobutyronitrile) as an initiator was added dropwise to the ethyl acetate and reacted under reflux for 8 hours. After the reaction, 110 g of ethyl acetate was added to obtain a solution of acrylate resin p-1 with a weight-average molecular weight (Mw) of 510,000 (non-volatile content 45%). Furthermore, 100 parts of a solution of acrylate resin p-1 and 3 parts of an isocyanate-based curing agent (Mittec GP105A, manufactured by Mitsubishi Chemical Corporation: tolylene diisocyanate, trimethylolpropane adduct) were stirred and mixed, and methyl ethyl ketone was added as a solvent to prepare a solution of acrylic adhesive (P-1) (non-volatile content 45%).

[0078] <Manufacturing of acrylic adhesive (P-2) solution> In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, and thermometer, 500 g of ethyl acetate was heated in a water bath while introducing nitrogen gas. Subsequently, a mixture of 120 g of BA (n-butyl acrylate), 360 g of 2-EHA (2-ethylhexyl acrylate), 20 g of AA (acrylic acid), and 0.3 g of AIBN (azobisisobutyronitrile) as an initiator was added dropwise to the ethyl acetate and reacted under reflux for 8 hours. After the reaction, 110 g of ethyl acetate was added to obtain a solution of (meth)acrylate resin p-2 with a weight-average molecular weight (Mw) of 800,000 (non-volatile content 45%). Furthermore, 100 parts of the acrylate resin p-2 solution and 3 parts of the isocyanate-based curing agent (Mitsubishi Chemical Corporation (Mytec GP105A): tolylene diisocyanate, trimethylolpropane adduct) were stirred and mixed, and methyl ethyl ketone was added as a solvent to prepare a solution of acrylic adhesive (P-2) (non-volatile content 45%).

[0079] <Manufacturing of acrylic adhesive (P-3) solution> 100 parts of a solution of acrylate resin p-2 (45% non-volatile content), 10 parts of O-130P (manufactured by Adeka, epoxidized soybean oil), and 3 parts of an isocyanate-based curing agent (manufactured by Mitsubishi Chemical Corporation (Mytec GP105A): tolylene diisocyanate, trimethylolpropane adduct) were stirred and mixed, and methyl ethyl ketone was added as a solvent to prepare a solution of acrylic adhesive (P-3) (45% non-volatile content).

[0080] <Manufacturing of Elastomer Adhesive (P-4) Solution> In a four-necked flask equipped with a stirrer, thermometer, reflux condenser, dropping device, and nitrogen inlet tube, 100 parts of Quintac 3270 (manufactured by Zeon Corporation, styrene content 24% by weight, diblock content 67% by weight) as the elastomer, and appropriate amounts of methyl ethyl ketone and toluene as solvents were charged under a nitrogen atmosphere. The flask was then gradually heated and continued heating at an internal temperature of approximately 50°C for 3 hours. After heating, the mixture was cooled to an internal temperature of approximately 40°C or lower. 39 parts of YS Polystar T130 (manufactured by Yasuhara Chemical Co., Ltd., softening point 130±5°C, hydroxyl value 60 mg KOH / g) were added as tackifying resin, 10 parts of O-130P (manufactured by Adeka Co., Ltd., epoxidized soybean oil) were added, and 2 parts of Irganox 1010 (manufactured by BASF Japan, antioxidant) were added as an antioxidant. The mixture was diluted with methyl ethyl ketone and toluene, and stirring was continued until the tackifying resin dissolved. 1 part of an isocyanate-based curing agent (Mittec GP105A, manufactured by Mitsubishi Chemical Corporation: tolylene diisocyanate, trimethylolpropane adduct) was added to obtain a solution of elastomer adhesive (P-4) (non-volatile content 40%).

[0081] Release sheet <fa-1>Manufacturing A PET release sheet "RF2PETCS001-50" (thickness: 50 μm, one side silicone release treatment, Rc: 0.2 μm) manufactured by I'm Co., Ltd., measuring approximately 30 cm x 30 cm, was passed between a metal roll and a rubber roll with a PG7 pattern (sand texture) owned by Godo Resin Industry Co., Ltd., under the conditions of temperature: 220°C, pressure: 5 MPa, and speed: 3 m / min, thereby transferring the sand texture pattern to the release sheet FA-1. The Rc value measured using the above method with a laser microscope (Keyence VK-X100) was 6.1 μm. The thickness of the PET release sheet is the average value obtained by measuring five arbitrary points using a Lightmatic VL-50B thickness gauge (manufactured by Mitutoyo Corporation), with a Φ7.5 mm probe and a pressing pressure of 0.01 N.

[0082] Release sheet <fa-2> ~ <fa-6>Manufacturing Except for using metal rolls with PG16, PG12, PG14, PG18, and PG68 patterns owned by the same company as for release sheet FA-1, sand-textured release sheets FA-2 to FA-7 were obtained under the same processing conditions as for release sheet FA-1, except that metal rolls with PG7 patterns owned by the same company were used instead of metal rolls with PG7 patterns owned by the same company.

[0083] Release sheet <fa-7> ~ <fa-10>Manufacturing After obtaining release sheets FA-3, FA-4, FA-5, and FA-6, release sheets FA-7, FA-8, FA-9, and FA-10 were obtained by passing each release sheet between a smooth metal roll and a rubber roll under the conditions of temperature: 110°C, pressure: 3.0 MPa, and speed: 0.5 m / min.

[0084] Release sheet <fa-11>Manufacturing Instead of using the PG7 patterned metal roll owned by Gōdō Jushi Kōgyō Co., Ltd., a metal roll with a grid pattern (line width 200 μm, line height 26 μm, grid pattern of 1400 μm × 1400 μm) owned by the same company was used. Under the same processing conditions as for release sheet FA-1, "RF2PETCS001-50" was passed between the metal roll and the rubber roll at a temperature of 220°C, a pressure of 5 MPa, and a speed of 3 minutes / m to obtain the grid-patterned release sheet FA-11.

[0085] Release sheet <fa-12>Manufacturing Except for using a metal roll with a PG27 pattern owned by the same company as for release sheet FA-1, a sand-textured release sheet FA-12 was obtained under the same processing conditions as for release sheet FA-1.

[0086] Release sheet <fa-13>Manufacturing Instead of using a metal roll with a PG7 pattern owned by Gōdō Jushi Kōgyō Co., Ltd., a release sheet FA-13 was obtained by passing "RF2PETCS001-50" between a metal roll with a grid pattern (line width 200 μm, line height 26 μm, grid pattern of 1400 μm × 1400 μm) owned by the same company and a rubber roll, under the conditions of temperature: 200℃, pressure: 1.0 MPa, and speed: 15 m / min, thereby transferring the aforementioned sand-textured pattern.

[0087] The Rc values ​​for each of the release sheets FA-1 to FA-12 described in detail are as follows. Transferred FA-1 PG7 (sand pattern). Rc: 6.1μm Transferred FA-2 PG16 (sand pattern). Rc: 8.3μm Transferred FA-3 PG12 (sand pattern). Rc: 11.5μm Transferred FA-4 PG14 (sand pattern). Rc: 21.2μm Transferred FA-5 PG18 (sand texture). Rc: 33.1 μm Transferred FA-6 PG68 (sand pattern). Rc: 38.7μm • FA-7 release sheet FA-3 processed. Rc: 9.7μm • FA-8 release sheet FA-4 was processed. Rc: 16.3μm • FA-9 is processed from FA-5 release sheet. Rc: 28.7μm • FA-10 processed from FA-6 release sheet. Rc: 35.8μm • FA-11 grid pattern transfer. Rc: 25.4 μm Transferred FA-12 PG27 (sand pattern). Rc: 48.0 μm • FA-13 grid pattern transfer. Rc: 4.2 μm

[0088] <Release Sheet FB> • FB-1 RF2PETCS001-50, manufactured by I'm Co., Ltd., PET release sheet (thickness: 50 μm, one side silicone release treatment, Rc: 0.2 μm)

[0089] <Other release sheets> • Apply BYK's silicone treatment agent "BYK300" to the matte side and the gloss side of FH-21 matte grade polyester film (Unitika Corporation, Emblet "PTH-38") using a coil bar at a rate of 0.1g / m². 2 A film coated and prepared as a release surface. Rc: 1.5μm·FH-22 Matte grade polyester film (Unitika Corporation, Emblet "PTH-38") was coated with BYK's silicone treatment agent "BYK300" at a rate of 0.1g / m² using a coil bar on both the gloss side and the opposite matte side. 2 A film coated with the film and used as the release surface. Rc: 1.5 μm

[0090] <Sheet-like substrate F> • Sheet-type substrate F-1: PET25 Unitika PET film (thickness: 25μm) • Sheet-type substrate F-2: PET75, Unitika Corporation PET film (thickness: 75μm) • Sheet-type substrate F-3: PET5 Unitika Corporation PET film (thickness: 5μm)

[0091] <Example 1> Manufacturing of an adhesive sheet for fixing a polishing pad, and an adhesive sheet for fixing a polishing pad with a release sheet. A solution of adhesive P-1 was applied to the release surface of release sheet FA-1 to a thickness of 50 μm after drying using a doctor blade, and then dried in an 80°C oven to form adhesive layer A-1. Sheet-like substrate F-1 was then bonded to the surface of adhesive layer A-1 using a hand roller. Separately, a solution of adhesive P-2 was applied to the release surface of release sheet FB-1 to a thickness of 50 μm using a doctor blade after drying, and the adhesive layer B-1 was formed by drying in an 80°C oven. Next, by using a hand roller to bond the side of adhesive layer B-1 opposite to the side of adhesive layer A-1 to the side of adhesive layer B-1 opposite to the release sheet FB-1 via the sheet-like substrate F-1, an adhesive sheet for fixing polishing pads with a laminated structure of [adhesive layer A-1 / sheet-like substrate F-1 / adhesive layer B-1] was obtained, in which the release sheet FA-1 was attached to adhesive layer A-1 and the release sheet FB-1 was attached to adhesive layer B-1. The properties of the obtained adhesive sheet (Beck smoothness of the outer surface of the release sheet FA, average roughness Rc, cross-section level difference Rδc of the contour curve, and crustosis Rku) were determined according to the method described later. Furthermore, the performance of the obtained adhesive sheets (ease of application, air release properties, adhesive strength, alkali resistance, holding power, and polishing accuracy) was evaluated according to the method described later.

[0092] <Examples 2-11> An adhesive sheet for fixing a polishing pad with a release sheet was obtained in the same manner as in Example 1, except that the release sheets to which the adhesive P-1 solution was applied were FA-2 to FA-11, as shown in Table 1, instead of the release sheet FA-1.

[0093] <Examples 12-16> An adhesive sheet for fixing a polishing pad with a release sheet was obtained in the same manner as in Example 1, except that release sheet FA-5 or FA-3 was used instead of release sheet FA-1, and as shown in Table 1, the solution of adhesive P-4 was used instead of the solution of adhesive P-1, the thickness of adhesive layer A was changed, the sheet-like substrate was changed, and the type and thickness of adhesive layer B were changed.

[0094] <Comparative Examples 1-4> An adhesive sheet for fixing a polishing pad with a release sheet was obtained in the same manner as in Example 1, except that the release sheets to which the adhesive P-1 solution was applied were FH-21, FH-22, FA-12, and FA-13, as shown in Table 1, instead of the release sheet FA-1.

[0095] [Properties of adhesive sheets] <Beck smoothness> The release sheet FB covering the adhesive layer B was peeled off from the adhesive sheet for fixing the polishing pad with a release sheet prepared in the examples and comparative examples. The exposed adhesive layer B was then bonded to a 100 μm PET film (Rc: 0.2 μm) and cut to a size of 50 mm square. Next, two samples are stacked on top of each other, and a hole is formed in the center using a Thomson die to create a circular hole with a radius of 5 mm, which is then used as the sample for measurement. The Beck smoothness meter (manufactured by Kumagai Riki Kogyo Co., Ltd.) is used to place the sample on a glass plate such that the outer surface of the release sheet FA of the sample is in contact with the glass plate, and the hole in the sample is positioned directly above the central circular hole on the glass plate. A rubber press plate is placed on the top surface of the PET film at the top of the sample, and a pressure of 0.1 MPa is applied via a pressure plate. Suction is then applied from below the central circular hole in the glass component to reduce the pressure to -50.7 kPa. Once -50.7 kPa is reached, the pressure reduction is stopped, and the time taken for the pressure to change from -50.7 kPa to -48.0 kPa (condition 1) and the time taken for the pressure to change from -50.7 kPa to -29.3 kPa (condition 2) are measured five times each. The average value is calculated and then divided by 2, the number of layers stacked. If even one of the five measurements exceeds 1000 seconds, the measurement is stopped, and ">1000" is recorded in the table. Furthermore, if even one of the five measurements showed low smoothness and a measurement time of less than 0.1 seconds, or if the air inflow was too high and the vacuum level did not rise to -50.7 kPa, then "0" was recorded in the table.

[0096] <Rc、Rδc、Rku> A vapor-deposited film approximately 20 nm thick was formed on the surface of the sheet to be measured using Vacuum Devices Co., Ltd.'s "MSP15" under the conditions of target: Pt-Pd, operating time: 1 minute, so that the laser from a laser microscope (KEYENCE VK-X100) reflected off the outermost surface of the sheet. Measurements were taken using a laser microscope in accordance with JIS B 0601 (2013).

[0097] [Evaluation of adhesive sheets] <Ease of application (position adjustment)> The procedure will be explained according to Figure 8. As shown in Figure 8-1, the adhesive sheets for fixing polishing pads with release sheets prepared in the examples and comparative examples were cut to a size of 210 mm square, the release sheet FB was peeled off to expose the adhesive layer B, and it was bonded to a smooth glass plate (approximately 300 g) measuring 200 mm square with a thickness of 3 mm in a 23°C-50% RH atmosphere. The adhesive sheets that protruded from all four sides of the glass plate were removed with a cutter to create a sample (hereinafter referred to as the sample) with the configuration of [glass / adhesive sheet / release sheet FA] measuring 200 mm square for evaluating the workability of bonding. Note that in Figure 8, the laminated state of the adhesive sheets and the laminated state of the adhesive sheets and release sheet FA are omitted. As shown in Figure 8-2, two types of frame lines, 200mm square and 150mm square, are drawn on one side of a 300mm square glass plate approximately in the center using a 1mm thick oil-based marker, and this is used as the evaluation substrate (hereinafter referred to as the substrate). As shown in Figure 8-3, peel off the release sheet FA from the sample to expose the adhesive layer A, and place the 200mm square sample on the substrate so that at least 10mm of each side extends beyond two sides of the 200mm square outer frame drawn on the substrate. Note that the surface on which the sample is placed should be the opposite side from the side on which the two types of frames were drawn. Immediately after placement, the sample was peeled off the substrate, and as shown in Figure 8-4, its position was adjusted to align with the 200 mm square frame of the substrate. The time taken from placement to peeling and re-application was then measured. Five randomly selected individuals performed the task, each scoring as follows. The total score from all five individuals was then used to evaluate the ease of application. The ease of application was scored as follows: 3 points: I was able to easily align it with the frame lines in under 10 seconds. 2 points: Alignment was completed in over 10 seconds but less than 15 seconds. 1 point: Alignment was completed in over 15 seconds but less than 30 seconds. 0 points: You exceeded 30 seconds. The evaluation criteria for ease of application are as follows: S:13-15 points A:10-12 points B: 7-9 points C: 4-6 points D: 0-3 points

[0098] <Evaluation of air release properties> As shown in Figure 9-1, immediately after evaluating the bonding workability, a 500g balance weight with a diameter of 41mm and a height of 63mm was placed in the center of each of the five evaluation samples and left undisturbed for 180 seconds. Next, as shown in Figure 9-2, the weight was removed, and points were assigned based on the number of air pockets with a diameter of 5mm or more inside a 150mm square frame on the adherend side (the back surface of the 300mm square glass plate), and the presence or absence of air pockets with a diameter of 10mm or more. Furthermore, the air release ability was evaluated from the total score of the five samples. The scoring criteria for air leakage were determined as follows: 3 points: There are no air pockets with a diameter of 5mm or more within the frame. Two points: There are 1-2 air pockets with a diameter of 5mm or more within the frame, and no air pockets with a diameter of 10mm or more. 1. There are 3 to 5 air pockets with a diameter of 5mm or more within the frame, and no air pockets with a diameter of 10mm or more. 0 points: There are more than 5 air pockets with a diameter of 5mm or more within the frame, and there are air pockets with a diameter of 10mm or more. The evaluation criteria for air release performance are as follows: S:13-15 points A:10-12 points B: 7-9 points C: 4-6 points D: 0-3 points

[0099] [Preparation of adhesive samples for measuring adhesive performance] <Evaluation of initial adhesion of adhesive layer A> Under a 23°C-50%RH atmosphere, the release sheet FB was peeled off from the adhesive sheet used to fix the polishing pad with a release sheet attached. The exposed adhesive layer B was bonded to a 25μm PET film, cut to a size of 25mm wide x 100mm long, and used as a sample for adhesive strength evaluation. Subsequently, the release sheet FA was peeled off, and the exposed adhesive layer A was placed on a stainless steel plate. A 2kg roller was passed back and forth once to press adhesive layer A to the stainless steel plate. After being left for 24 hours, the adhesive strength of adhesive layer A (adhesion strength to SUS) was measured in accordance with the measurement method of JIS Z1528, under a 23°C-50%RH atmosphere, using a tensile testing machine with a peeling angle of 180 degrees and a peeling speed of 0.3m / min. The obtained measured values ​​are shown in Table 1.

[0100] <Evaluation of chemical resistance> The release sheet FA was peeled off the sample for adhesion strength evaluation, and the exposed adhesive layer A was placed on a stainless steel plate. A 2kg roller was passed back and forth once to press the adhesive layer A onto the stainless steel plate. Within 30 minutes, the sample was immersed in a pH 11.5 sodium hydroxide aqueous solution while still attached to the stainless steel plate, and left for 24 hours at 40°C. After that, the sample was removed from the sodium hydroxide aqueous solution, washed with water, and left for 1 hour at 23°C and 50%RH. The adhesive strength was measured using the same method as described above for <Initial Adhesion Measurement>, and this was defined as <Adhesion after Immersion>. The difference between the initial adhesive strength and the adhesive strength after immersion was then calculated. A smaller difference indicates superior chemical resistance. The criteria for evaluating chemical resistance are as follows: A: Difference in adhesive strength is 1.5N / 25mm or less - extremely good. B: Adhesion difference of 1.5N / 25mm or more, and less than 2.0N / 25mm: Good C: Adhesion difference of 2.0 N / 25 mm or more, and less than 3.0 N / 25 mm: Usable. D: If the difference in adhesive strength is 3.0N / 25mm or more, it cannot be used. In CMP (Chemical Polishing) processes, which use various chemical solutions depending on the material being polished, strong chemical resistance is required. S is the best, A is preferred, B is used for general purposes, C has limited applications, and D cannot be used.

[0101] <Evaluation of holding power> The release sheet FA was peeled off the sample used for adhesion strength evaluation. Only a 25mm wide x 25mm long area of ​​the exposed adhesive layer A was placed on a stainless steel plate and a 2kg roller was passed back and forth once to press the adhesive layer A onto the stainless steel plate. After pressing the adhesive layer A onto the stainless steel plate, it was left in an atmosphere of 23°C - 50%RH for 20 minutes. Subsequently, a 1kg weight was attached to the edge of the sample that was not attached to the stainless steel plate and set up so that a force was applied in a 180-degree direction in an atmosphere of 80°C. After 24 hours, the amount of displacement in mm of the attachment position was measured. In addition, if the sample completely detached from the substrate, the time until it fell was measured. The criteria for evaluating holding power are as follows: S: Displacement less than 0.1 mm A: 0.1 mm or more, less than 1.0 mm B: Displacement of 1.0 mm or more, and 5.0 mm or less. C: Falling after 180 minutes D: Falling in less than 180 minutes The smaller the displacement, the less likely slippage or peeling is to occur during polishing, and the stronger the polishing pad can be fixed, making it suitable for various polishing processes. S is the best, A is suitable for general use, B is suitable for general use, C has limited applications, and D cannot be used.

[0102] <Polishing precision> The release sheet FB was peeled off from the adhesive sheet used to fix the polishing pad with a release sheet, and the non-polishing surface of the polishing pad (CMP cloth manufactured by Musashino Electronics, Φ200mm, normal type) was placed on the exposed adhesive layer B. The pads were then bonded together under the conditions of roll temperature: 80℃, pressure: 0.1MPa, and speed: 1.0M / min to produce a polishing pad with an adhesive sheet. A Musashino Electronics MA-200 was used as the polishing device. The release sheet FA was peeled off from the prepared adhesive-backed polishing pad, and the exposed adhesive layer A was attached to an aluminum surface plate. Intermediate polishing was then performed under the following conditions. (conditions) Table rotation speed: 100 rpm Head rotation speed: 105 rpm Test piece to be polished: A 200mm wafer (75μm thick) with a polysilicon layer (500nm) deposited on its surface, cut into a 3cm square. Polishing pressure: 10.0 kPa Polishing time: 15 min Polishing solution: Colloidal silica polishing compound #80 manufactured by Musashino Electronics Co., Ltd. After polishing, the test specimens were washed with water and the water droplets were removed with compressed air. Then, the thickness of the polysilicon was measured at three arbitrary points (one at the center and two at points outside the center) using an Otsuka Electronics FE-300 film thickness gauge. The polishing accuracy was evaluated based on the difference between the maximum and minimum film thicknesses according to the following criteria. S: Less than 10nm A: 10nm or more, less than 20nm B: 20nm or more, less than 30nm C: 30nm or more, less than 50nm D: 50nm or more In CMP polishing, where precision is required, S is the best, A is preferred, B is used for general purposes, C has limited applications, and D cannot be used.

[0103] [Table 1] [Explanation of Symbols]

[0104] 0: Adhesive sheet for fixing the polishing pad 1: Adhesive sheet for fixing polishing pad with release sheet FA 2: Adhesive sheet for fixing polishing pad with release sheet FA and release sheet FB 3: Polishing pad with release sheet FA 4: Polishing pad with adhesive sheet for fixing the polishing pad in place A: Adhesive layer A FA: Release sheet covering the surface of adhesive layer A FA': Precursor of FA B: Adhesive layer B FB: Release sheet covering the surface of adhesive layer B F: Sheet-like substrate PP: Polishing pad R1: Metal roll R2: Rubber Roll SP: Surface plate E: Rubber retaining plate G: Glass surface H: Pressure plate PET: PET film < / fa-7> < / fa-2>

Claims

1. An adhesive sheet for fixing a polishing pad with a release sheet FA, comprising an adhesive layer A on one side of a sheet-like substrate, an adhesive layer B on the other side of the sheet-like substrate, and the surface of adhesive layer A that is not in contact with the sheet-like substrate in contact with a release sheet FA, The material of the aforementioned release sheet FA is a plastic film that does not contain paper. The outer surface of the release sheet FA that is not in contact with the adhesive layer A has irregularities, and in the Beck smoothness test, The smoothness of the outer surface of the release sheet FA, as determined by the following condition 1, is 0.1 to 30 seconds. The smoothness of the outer surface of the release sheet FA, as determined by condition 2 below, is 1 to 500 seconds. An adhesive sheet for fixing polishing pads, characterized by having a release sheet FA. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: The time it takes for the pressure to change from -50.7 kPa to -29.3 kPa.

2. The adhesive sheet for fixing a polishing pad with a release sheet FA according to claim 1, characterized in that the average height Rc of the surface irregularities on the outer surface of the release sheet FA is 12 to 42 μm.

3. The adhesive sheet for fixing a polishing pad with a release sheet FA according to claim 2, characterized in that the cutting level difference Rδc of the contour curve of the unevenness on the outer surface of the release sheet FA is 5 to 25 μm, and the kurtosis Rku is less than 3.

4. The adhesive sheet for fixing a polishing pad with the release sheet FA according to claim 3, characterized in that the shape of the convex portion on the outer surface of the release sheet FA is irregular and irregular in plan view.

5. The adhesive sheet for fixing a polishing pad with a release sheet FA according to claim 4, characterized in that the adhesive layer A is an acrylic adhesive layer.

6. The adhesive sheet for fixing the polishing pad with a release sheet FA as described in any one of claims 1 to 5, and the release sheet FB, The release sheet FB is in contact with the side of the adhesive layer B that is not in contact with the sheet-like substrate. The adhesive sheet for fixing a polishing pad, characterized in that the material of the release sheet FB is a plastic film that does not contain paper, and includes a release sheet FA and a release sheet FB.

7. An adhesive sheet for fixing a polishing pad with a release sheet FA according to any one of claims 1 to 5, wherein the sheet is wound in a roll shape and the length in the width direction of the wound body is 1000 mm or less.

8. An adhesive sheet for fixing a polishing pad, comprising a release sheet FA and a release sheet FB according to claim 6, wherein the sheet is wound in a roll shape and the length in the width direction of the wound body is 1000 mm or less.

9. An adhesive sheet for fixing a polishing pad, with release sheet FA and release sheet FB according to claim 6, wherein the length of the shorter side is 1000 mm or less.

10. A polishing pad with an adhesive layer comprising a polishing pad and an adhesive sheet for fixing the polishing pad with a release sheet FA as described in any one of claims 1 to 5, A polishing pad with a release sheet FA and adhesive layer A, in which the polishing pad and adhesive layer B are in contact.

11. A method for fixing a polishing pad to a surface plate via an adhesive sheet, characterized by peeling off the release sheet FA from the polishing pad with the release sheet FA and adhesive layer A as described in claim 10, and attaching the adhesive layer A to the surface plate.

12. A method for manufacturing an adhesive sheet for fixing a polishing pad, comprising a release sheet FA, an adhesive layer A, a sheet-like substrate, an adhesive layer B, and a release sheet FB, wherein the release sheet FA and the release sheet FB are attached. The process comprises the following steps (1) to (4): (1) A step of applying adhesive a to the surface of a release sheet FA having an average height Rc of surface irregularities Rc of 12 to 42 μm to form an adhesive layer A. (2) A step of overlapping a sheet-like substrate onto the surface of the adhesive layer A that is not in contact with the release sheet FA. (3) A step of applying adhesive b to the peeled surface of the release sheet FB to form an adhesive layer B. (4) A step of overlapping the surface of the adhesive layer B that is not in contact with the release sheet FB onto the surface of the sheet-like substrate that is not in contact with the adhesive layer A. The outer surface of the release sheet FA that is not in contact with the adhesive layer A has irregularities, and in the Beck smoothness test, The smoothness of the outer surface of the release sheet FA, as determined by the following condition 1, is 0.1 to 30 seconds. The smoothness of the outer surface of the release sheet FA, as determined by condition 2 below, is 1 to 500 seconds. A method for manufacturing adhesive sheets for fixing polishing pads, with release sheets FA and FB. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: The time it takes for the pressure to change from -50.7 kPa to -29.3 kPa.

13. A method for manufacturing an adhesive sheet for fixing an abrasive pad, comprising a release sheet FA, an adhesive layer A, a sheet-like substrate, an adhesive layer B, and a release sheet FB, wherein the release sheet FA and FB are attached. The process comprises the following steps (5) to (8): (5) A step of applying adhesive a to one side of a sheet-like substrate to form an adhesive layer A. (6) A step of overlapping the surface of a release sheet FA, which has an average height Rc of surface irregularities Rc of 12 to 42 μm, onto the surface of the adhesive layer A that is not in contact with the sheet-like substrate. (7) A step of applying adhesive b to the peeled surface of the release sheet FB to form an adhesive layer B. (8) A step of overlapping the surface of the adhesive layer B that is not in contact with the release sheet FB onto the surface of the sheet-like substrate that is not in contact with the adhesive layer A. The outer surface of the release sheet FA that is not in contact with the adhesive layer A has irregularities, and in the Beck smoothness test, The smoothness of the outer surface of the release sheet FA, as determined by the following condition 1, is 0.1 to 30 seconds. The smoothness of the outer surface of the release sheet FA, as determined by condition 2 below, is 1 to 500 seconds. A method for manufacturing adhesive sheets for fixing polishing pads, with release sheets FA and FB. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: The time it takes for the pressure to change from -50.7 kPa to -29.3 kPa.

14. A method for manufacturing an adhesive sheet for fixing an abrasive pad, comprising a release sheet FA, an adhesive layer A, a sheet-like substrate, an adhesive layer B, and a release sheet FB, the method comprising the following steps (9) to (12): (9) A step of applying adhesive b to the peeled surface of the release sheet FB to form an adhesive layer B. (10) A step of overlapping a sheet-like substrate onto the surface of the adhesive layer B that is not in contact with the release sheet FB. (11) A step of applying adhesive a to the surface of a release sheet FA having an average height Rc of surface irregularities Rc of 12 to 42 μm to form an adhesive layer A. (12) A step of overlapping the surface of the adhesive layer A that is not in contact with the release sheet FA onto the surface of the sheet-like substrate that is not in contact with the adhesive layer B. The outer surface of the release sheet FA that is not in contact with the adhesive layer A has irregularities, and in the Beck smoothness test, The smoothness of the outer surface of the release sheet FA, as determined by the following condition 1, is 0.1 to 30 seconds. The smoothness of the outer surface of the release sheet FA, as determined by condition 2 below, is 1 to 500 seconds. A method for manufacturing adhesive sheets for fixing polishing pads, with release sheets FA and FB. Condition 1: Time taken for the pressure to change from -50.7 kPa to -48.0 kPa. Condition 2: The time it takes for the pressure to change from -50.7 kPa to -29.3 kPa.

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