JPS63310132A - Adhesive sheet for bonding of wafer - Google Patents

Abstract

PURPOSE:To uniformly stretch individual wafer chips bonded to an adhesive agent layer of an adhesive sheet in a face direction in order to separate the chips from one another at nearly equal intervals and to make a subsequent picking-up operation easy by a method wherein the rear of a substrate material formed on the surface of the adhesive agent layer is roughened. CONSTITUTION:When an expanding operation is executed after a semiconductor wafer A bonded to an adhesive agent layer 12 in an adhesive sheet 10 has been diced, a pressure jig 5 is pressed to the rear of a substrate material 11 in the adhesive sheet 10, Because the rear of the substrate material 11 is roughened, the pressure jig 5 is brought into contact with the rear of the roughened substrate material 11 in a point-contact manner; the friction is reduced sharply as compared with a conventional method; the substrate material 11 in the adhesive sheet 10 glides suitably on the surface of the pressure jig. By this setup, the adhesive sheet 10 is stretched uniformly; individual wafer chips A1-A5 bonded to the adhesive agent layer 12 in the adhesive agent 10 are separated from one another at nearly equal intervals; a subsequent picking-up process can be executed easily.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an adhesive sheet, and more particularly to an adhesive sheet for adhering a wafer used when cutting and separating a semiconductor wafer into small pieces.

Technical Background and Problems Semiconductor wafers such as silicon and gallium arsenide are manufactured in a large diameter state, and after this wafer is cut and separated into small element pieces (dicing), it is transferred to the next process, the mounting process. ing. At this time, the semiconductor wafer is previously attached to an adhesive sheet and subjected to the following steps: dicing, cleaning, drying, expanding, picking up, and mounting.

In such a semiconductor wafer extracting process, as shown in FIG. Fix it with tools 4, 4, press the back side of the base material 2 side of this adhesive sheet 1 with a pressing jig 5,
Stretch the adhesive sheet 1 in the surface direction and attach each wafer chip A.
It was necessary to separate the distance between wafer chips A1 to A5 approximately evenly to make the subsequent pick-up process easier.In the pick-up process, each wafer chip A1 to A5 was picked up one by one using air tweezers or the like. , at that time,
If the distance between each of the wafer chips A1 to A5 is unrestricted or not sufficiently spaced apart, the picking up operation becomes complicated, which is undesirable.

However, when the expanding process shown in FIG. 7 is performed using the conventional adhesive sheet 1, an excessive frictional force is generated between the base material 2 of the adhesive sheet 1 and the pressing jig 5, and the adhesive sheet 1 is damaged. When stretched in the plane direction, it is stretched non-uniformly, resulting in uneven or insufficient spacing between 1 and A5 on each wafer chip, which may complicate the pick-up process. .

In particular, when the pick-up process is performed using a pyramidal collet 6 as shown in Fig. 8 (which is often used in the pick-up process because it does not damage the wafer chip surface), the distance between each wafer chip is narrow. Since the tip of the pyramidal collet 6 comes into contact with an adjacent wafer chip, there is a possibility that it may become impossible to pick up the target wafer chip.

Purpose of the Invention The present invention was designed to eliminate such inconveniences, and includes a method for expanding a wafer pasting sheet used for cutting and separating semiconductor wafers.
To provide a pressure-sensitive adhesive sheet for wafer attachment, which is uniformly stretched in the surface direction so that each wafer chip attached to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet is separated from each other substantially equally, thereby facilitating subsequent pick-up work. With the goal.

1 Skin View I In order to achieve the above object, the adhesive sheet according to the present invention is a wafer adhesive sheet comprising an adhesive layer to which a semiconductor wafer is attached, and a base material on which this adhesive layer is formed. The pressure-sensitive adhesive sheet is characterized in that the surface of the base material is roughened.

In the adhesive sheet for attaching wafers according to the present invention, when expanding the semiconductor wafer attached to the adhesive layer of the adhesive sheet after dicing, the pressing jig is used to move the pressing jig to the base material of the adhesive sheet. However, since the back side of this base material has been roughened, the contact between the pressing jig and the roughened back side of the base material is point contact, compared to conventional methods. Friction is significantly reduced. Therefore, when pressing the back side of the base material with the pressing jig and stretching the adhesive sheet in the surface direction, the base material in the adhesive sheet slides conveniently on the surface of the pressing jig, and the adhesive sheet is stretched uniformly. It will be.

Therefore, the wafer chips attached to the adhesive layer of this adhesive sheet are spaced approximately evenly apart from each other, facilitating the subsequent pick-up process.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Fig. 1 is a cross-sectional view of a pressure-sensitive adhesive sheet for wafer attachment showing an embodiment of the present invention, Figs. 2 and 3 are cross-sectional views of main parts showing the state of use of the pressure-sensitive adhesive sheet, and Fig. 4 is a manufacturing process of the pressure-sensitive adhesive sheet. FIG.

As shown in FIGS. 1 and 2, the adhesive sheet 10 for attaching wafers according to an embodiment of the present invention consists of a base material 11 and an adhesive layer 12 applied to the surface of the base material 11. In order to protect this adhesive layer 12, a releasable sheet 13 is temporarily attached to the surface of the adhesive layer 12, as shown in FIG.

In the present invention, the back surface of the base material 11 is roughened. A large number of small irregularities 15 are formed. The surface roughening treatment for forming such unevenness 15 is performed, for example, in the fourth step.
As shown in the figure, an embossing roll 20 and a metal roll 21
The base material 11 on which the adhesive layer 12 is not yet formed is sent out from the die 22 between the two, and the back surface of the base material 11 is passed through the embossing roll 20 side so as to be pressed against the embossing roll 20 side for embossing. Further, a large number of small irregularities 15 may be formed on the back surface of the base material 11 by other surface roughening treatments such as sandblasting, etching, and electrical discharge machining.

The shape of the adhesive sheet 10 can be any shape such as a tape shape or a label shape. Examples of the material for the base material 11 include polyethylene or polyethylene copolymers such as ethylene-vinyl acetate copolymers, ethylene-methacrylic acid copolymers, polypropylene, polybutylene, ionomers, polybutadiene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene terephthalate. Methylpentene, polyurethane, polyvinyl chloride or polyvinyl chloride copolymer, or rubber-based materials are used. Particularly preferably, materials with good extensibility and restorability are used.
Flexible films such as ethylene-methacrylic acid copolymer, polyvinyl chloride, ionomer, ethylene-vinyl acetate copolymer, and rubber are preferable.

As will be described later, the adhesive sheet of this example is irradiated with radiation such as EB or U. Although it does not have to be a transparent material, it is necessary to use a transparent material when it is used with U■ pre-irradiation.

An adhesive layer 12 is provided on the base material 11 as described above, and in this example, the adhesive layer 12 is formed of lv containing an adhesive and a radiation polymerizable compound. There is.

As the adhesive 12, a wide variety of conventionally known adhesives can be used, but acrylic adhesives are preferred, and specifically, those selected from homopolymers and copolymers containing acrylic acid ester as the main constituent monomer unit. These include copolymers with acrylic polymers and other functional monomers, and mixtures of these polymers. For example, monomer acrylic esters include ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, glycidyl methacrylate, 2-hydroxyethyl methacrylate, and the above-mentioned methacrylic acids. Those in place of acrylic acid can also be preferably used.

In order to increase the compatibility with the oligomers described below, (
A hexamer such as meth)acrylic acid, acrylonitrile, and vinyl acetate may be copolymerized.

The molecular weight of the acrylic polymer obtained by polymerizing these monomers is 2.0XIO" to 10.0X10, preferably 4.0X10" to 8.0X105.

In addition, as radiation polymerizable compounds, for example, JP-A-60
-196.956 Publication and JP-A-60-223,1
Low molecular weight compounds having at least two or more photopolymerizable carbon-carbon double bonds in the molecule that can be formed into a three-dimensional network by light irradiation, as disclosed in Japanese Patent Application No. 39, are widely used. Methylolpropane triacrylate, tetramethylolmethanetetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1,4-butylene glycol diacrylate, 1.6 -hexanediol diacrylate, polyethylene glycol diacrylate,
Commercially available oligoester acrylates and the like are used.

Further, as the radiation polymerizable compound, in addition to the above-mentioned acrylate compounds, urethane acrylate oligomers can also be used. The urethane acrylate oligomer is a polyol compound such as a polyester type or polyether type, and a polyvalent isocyanate compound such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate. , 1,4-xylylene diisocyanate, diphenylmethane 4,4-diisocyanate, etc., to a terminal isocyanate urethane prepolymer obtained by reacting a (meth)acrylate having a hydroxyl group, such as 2-hydroxyethyl (meth)acrylate. , 2-hydroxypropyl (meth)acrylate, polyethylene glycol (meth)acrylate, etc. This urethane acrylate oligomer is a radiation polymerizable compound having at least one carbon-carbon double bond.

As such urethane acrylate oligomer,
In particular, the molecular weight is 3,000 to 10,000, preferably 4,000.
It is preferable to use one having a molecular weight of 8,000 to 8,000, because even if the surface of the semiconductor wafer is rough, the adhesive will not adhere to the chip surface when the wafer chip is picked up. In addition, when using a urethane acrylate oligomer together with a radiation polymerizable compound, JP-A-60-196.956
Compared to the case of using a low molecular weight compound having at least two photopolymerizable carbon-carbon double bonds in the molecule as disclosed in the above publication, an extremely superior pressure-sensitive adhesive sheet can be obtained. That is, the adhesive strength of the adhesive sheet before irradiation with radiation is sufficiently large, and the adhesive strength decreases sufficiently after irradiation with radiation, so that when a wafer chip is picked up, there is almost no adhesive left on the chip surface.

The blending ratio of the acrylic adhesive and urethane acrylate oligomer in the adhesive is 50 to 9 parts by weight of the urethane acrylate oligomer to 100 parts by weight of the acrylic adhesive.
It is preferable to use the upper end of the range of 0.00 parts by weight. In this case, the adhesive sheet obtained has a high initial adhesive strength, but the adhesive strength decreases significantly after radiation irradiation, and wafer chips can be easily picked up from the adhesive sheet.

Furthermore, if necessary, the adhesive layer 12 may contain, in addition to the above-mentioned adhesive and radiation polymerizable compound, a compound that is colored by radiation irradiation. By including a compound in the adhesive 12 that is colored by such radiation irradiation, the adhesive sheet is colored after being irradiated with radiation, thereby increasing the detection accuracy when detecting the wafer depth with an optical sensor. ,
No malfunction occurs when picking up the wafer depth. Furthermore, it is possible to immediately determine by visual inspection whether or not the adhesive sheet has been irradiated with radiation.

A compound that is colored by radiation irradiation is a compound that is colorless or pale colored before radiation irradiation, but becomes colored by radiation irradiation, and a preferred specific example of this compound is a leuco dye. As the leuco dye, conventional triphenylmethane-based, fluoran-based, phenothiazine-based, auramine-based, and spiropyran-based dyes are preferably used. Specifically, 3-[N-(p-tolylamino)]-7-anirite fluorane, 3-[N-(p-
tolyl)-N-methylamino]-7-anirithufluorane, 3-[N-(p-tolyl)-N-ethylamino 1
-7-anirite fluorane, 3-diethylamino -6
-Methyl-7-anilinofluorane, crystal violet lactone, 4.4',4'"-trisdimethylaminotriphenylmethanol, 4.4',4"-trisdimethylaminotriphenylmethane, and the like.

Color developers that are preferably used with these leuco dyes include electron acceptors such as conventionally used initial polymers of phenol-formalin resin, aromatic carboxylic acid derivatives, and activated clay. In some cases, various known coloring agents may be used in combination.

Such a compound that is colored by radiation irradiation may be dissolved in an organic solvent or the like and then contained in the adhesive layer, or may be made into a fine powder and contained in the adhesive layer. This compound is desirably used in the adhesive layer in an amount of 0.01 to 10% by weight, preferably 0.5 to 5% by weight. If the compound is used in an amount exceeding 10% by weight, the radiation applied to the adhesive sheet will be absorbed too much by the compound, resulting in insufficient curing of the adhesive layer, which is undesirable. If it is used in an amount less than .01% by weight, the adhesive sheet may not be sufficiently colored during radiation irradiation, and malfunctions may easily occur when picking up wafer chips, which is not preferable.

In some cases, the adhesive layer 12 may contain a light-scattering inorganic compound powder in addition to the above-mentioned adhesive and radiation polymerizable compound.

By including such a light-scattering inorganic compound powder in the adhesive layer 12, even if the surface of an adherend such as a semiconductor wafer turns gray or black for some reason, the adhesive sheet can be irradiated with radiation such as ultraviolet rays. Then,
Even in gray or black areas, the adhesive strength is sufficiently reduced, so that when picking up wafer chips, the adhesive will not stick to the wafer depth surface.
Moreover, the effect of having sufficient adhesive strength before irradiation with radiation can be obtained.

This light-scattering inorganic compound is a compound that can diffusely reflect radiation such as ultraviolet (UV) or electron beam (EB) when irradiated with it, and
Specific examples include silica powder, alumina powder, silica alumina powder, and mica powder. The light-scattering inorganic compound is preferably one that almost completely reflects the radiation as described above, but it is of course possible to use one that absorbs radiation to some extent.

It is preferable that the light-scattering inorganic compound is in the form of a powder, and the particle size thereof is preferably about 1 to 100 μm, preferably about 1 to 20 μm. This light-scattering inorganic compound is desirably used in the adhesive layer in an amount of 0.1 to 10% by weight, preferably 1 to 4% by weight. If the compound is used in an amount exceeding 10% by weight in the adhesive layer, it is not preferable because the adhesive force of the adhesive layer may decrease.
．． If it is less than 11% by weight, if the semiconductor wafer surface turns gray or black, even if that part is irradiated with radiation, the adhesive strength will not be sufficiently reduced and adhesive will remain on the wafer surface when picked up, which is undesirable. .

The adhesive sheet obtained by adding a light-scattering inorganic compound powder to the adhesive layer can be used even when the surface of a semiconductor wafer has turned gray or black for some reason. It is thought that the reason why the adhesive force is sufficiently reduced even in this part when the part is irradiated with radiation is as follows.

That is, the adhesive sheet 10 has an adhesive layer 12, but when this adhesive layer 12 is irradiated with radiation, the radiation-polymerizable compound contained in the adhesive layer 12 hardens and its adhesive strength decreases. It turns out. However, gray or black areas may appear on the semiconductor wafer surface for some reason. In such a case, if the adhesive layer 12 is irradiated with radiation, the radiation will pass through the adhesive layer 12 and reach the wafer surface, but if there is a gray or blackened area on the wafer surface, the radiation will not be transmitted to this area. absorbed,
There will be no more reflection. For this reason, the radiation that should originally be used for curing the adhesive layer 12 is absorbed by the gray or blackened areas, resulting in insufficient curing of the adhesive layer 12 and the adhesive strength not decreasing sufficiently. Become. Therefore, it is considered that the adhesive adheres to the chip surface when the wafer chip is picked up.

However, when a light-scattering inorganic compound powder is added to the adhesive layer 12, the irradiated radiation collides with the compound and changes its direction before reaching the wafer surface. Therefore, even if there is a gray or black area on the wafer chip surface, the diffusely reflected radiation will penetrate into the area above this area, and therefore this gray or black area will also be absorbed. harden. Therefore, by adding light-scattering inorganic compound powder to the adhesive layer,
Even if there is a gray or black area on the semiconductor wafer surface for some reason, the adhesive layer will not be sufficiently cured in this area, so the adhesive will adhere to the chip surface when the wafer depth is picked up. Things will go away.

Further, by mixing an isocyanate curing agent into the above-mentioned pressure-sensitive adhesive, the initial adhesive strength can be set to an arbitrary value. Examples of such curing agents include polyvalent isocyanate compounds such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate,
1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4°-diisocyanate, diphenylmethane-2,4°-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexame Dilene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4°-
Diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate, etc. are used.

In the above adhesive, if used for irradiation, add U■
By incorporating an initiator, it is possible to reduce the polymerization curing time due to U2 irradiation and the amount of U2 irradiation.

Specific examples of such U initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, and diacetyl. , β-chloranthraquinone, and the like.

The method of using the adhesive sheet according to the present invention will be explained below.

A releasable sheet 13 is provided on the upper surface of the adhesive sheet 10 according to the present invention.
is provided, the sheet 13 is removed, and then the adhesive sheet 10 is placed with the adhesive layer 12 facing upward, and the upper surface of the adhesive layer 12 is coated as shown in FIG. A semiconductor wafer A to be diced is attached. Wafer A is subjected to various processes such as dicing, cleaning, and drying in this adhered state. At this time, since the wafer chips are sufficiently adhered and held to the adhesive sheet by the adhesive layer 12, the wafer chips do not fall off during each of the above steps.

Next, as shown in FIG. 3, an expanding process is performed. In the expanding step, both ends of the adhesive sheet 10 on which the diced wafer chips 8 to A5 are adhered to the adhesive layer 12 are fixed with fixtures 4, 4, and the sides of the base material 11 of the adhesive sheet 10 are pressed and cured. Press with tool 5,
Stretch the adhesive sheet 10 in the plane direction. During this expanding process, the pressing jig 5 is attached to the adhesive sheet 10.
However, since the back surface of the base material 11 has been roughened, contact between the pressing jig 5 and the roughened surface of the base material 11 is difficult. This results in point contact, significantly reducing friction compared to conventional methods. Therefore, when pressing the back side of the base material 11 with the pressing jig 5 and stretching the adhesive sheet 10 in the surface direction, the base material 11 of the adhesive sheet 10 conveniently slides on the surface of the pressing jig 5, causing the adhesive Sheet 10 will be uniformly stretched. Therefore, the adhesive layer 1 in this adhesive sheet 10
The wafer chips attached to the wafer 2 are substantially evenly and sufficiently spaced apart from each other, and the quick pick-up process (particularly the pick-up process using a pyramidal collet) is facilitated.

Next, each wafer chip is picked up from the adhesive sheet and mounted on a predetermined base. At this time, ionizing radiation such as ultraviolet rays (tJV) or electron beams (EB) is applied before or during pickup. The adhesive layer 12 of the adhesive sheet 10 is irradiated, and the adhesive layer 1
The radiation polymerizable compound contained in 2 is polymerized and cured. When the radiation-polymerizable compound is polymerized and cured by irradiating the adhesive layer 12 with radiation in this manner, the adhesive force of the adhesive is greatly reduced, and only a small amount of adhesive force remains.

Note that it is preferable that the radiation irradiation to the adhesive sheet 10 be performed from the surface of the base material 11 on which the adhesive layer 12 is not provided. Therefore, as mentioned above, when using UV as radiation, the base material 11 needs to be light-transparent; however, when using 7TEB as radiation, the base material 11 does not necessarily have to be light-transparent. do not have.

After irradiating the adhesive layer 12 in the portions where the wafer chips A1 to A5 are provided with radiation to reduce the adhesive force of the adhesive layer 12, the adhesive sheet 10 is placed at a pick-up station (not shown). As shown in FIG. Chip A1
. . . is reliably picked up by, for example, a pyramidal collet 6, and mounted on a predetermined base. In this way, wafer chip A1. A2...
When the wafer chip is picked up, no adhesive adheres to the surface of the wafer chip, and the wafer chip can be easily picked up, resulting in good quality chips without contamination.

Particularly in the present invention, since sufficient and even intervals can be maintained between the chips attached to the adhesive layer 12 in the expanding step, it becomes easy to confirm the position of each chip using a sensor. Moreover, the pyramidal collet 6, which is often used for pickup, ensures that the wafer chip A7...
It becomes possible to pick up...

Note that the radiation irradiation can also be performed at a pickup station. It is not always necessary to irradiate the entire surface of the wafer A to which the wafer A is attached at once, and the irradiation may be performed in several parts. A
After irradiating each wafer chip with a radiation irradiation tube that irradiates only the corresponding back surface to reduce the adhesive strength of the adhesive in that part, the wafer chip is removed using the push-up needle rod 26. A1. It is also possible to pick up items in sequence by pushing up A2... FIG. 6 shows a modification of the above-mentioned radiation irradiation method. In this case, the push-up needle rod 26 is made hollow, and a radiation generator 8!27 is provided in the hollow part to perform radiation irradiation and pickup. In this way, the device can be simplified and the pick-up operation time can be shortened.

Note that the present invention is not limited to the embodiments described above, and can be modified in various ways.

For example, in the above embodiments, the adhesive layer contains a radiation-polymerizable compound, but the invention is not limited to this, and the adhesive layer may be made of only an adhesive.

Next, the results of tests conducted to confirm the effects of the present invention will be explained.

In order to confirm how much the sliding property of the central part of the base material against a jig in the adhesive sheet according to the present invention is improved compared to the conventional adhesive sheet, the respective static friction coefficients μ were compared. Note that the static friction coefficient μ is defined by the following formula.

μ=F/N However, F is the tensile force of the weight, and N is the weight of the weight.

As for the test method, J. TAPPI
) Conducted in accordance with the paper pulp test method. in particular,
A 1Kg weight is placed on the film as the measurement material, a stainless steel plate is placed under the film, and the weight is pulled together with the film using a nylon thread at a speed of 10 m/min, and the tensile force applied to the nylon thread at this time. .

This was done by measuring (F). The results are shown in Table 1.

Note that an ethylene methacrylic acid copolymer film was used as the special polyolefin film.

In addition, as a soft vinyl chloride film, plasticizer 35p
We used those containing

The above experimental results show that even for films with a large static friction coefficient and poor slip properties, roughening treatment can significantly reduce the friction coefficient and improve the slip properties. It has become clear that it can be used as a base material in the adhesive sheet according to the invention.

As described in detail, the present invention provides an adhesive sheet for wafer attachment comprising an adhesive layer to which a semiconductor wafer is attached, and a base material on which the adhesive layer is formed.
Since the back surface of the base material has been roughened, the adhesive sheet can conveniently slide on the surface of the pressing jig during the expanding process of the adhesive sheet for wafer attachment, so that the adhesive sheet can be stretched uniformly. The wafer chips attached to the adhesive sheet are separated from each other substantially evenly, and the subsequent pick-up process becomes extremely easy, which is an excellent effect.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a pressure-sensitive adhesive sheet for wafer attachment showing an embodiment of the present invention, Figs. 2 and 3 are cross-sectional views of main parts showing the state of use of the pressure-sensitive adhesive sheet, and Fig. 4 is a manufacturing process of the pressure-sensitive adhesive sheet. Figures 5 and 6 are sectional views of the main parts when the pick-up process is performed using the same adhesive sheet, and Figure 7 is a cross-sectional view of the main parts when the conventional adhesive sheet is used for the expanding process. FIG. 8 is a cross-sectional view of main parts showing a pickup process according to a conventional example. 10... Adhesive sheet 11... Base material, 12... Adhesive layer, 15...
...Irregularities, A...Wafer, A1-A5...
wafer chip. Agent Patent Attorney Shunichi Suzuki Part 1 Figure n Figure 2 b Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure Procedures Manual November 26, 1986 1. Indication 1988 Patent Application No. 146.446 2 Name of the invention Adhesive sheet for wafer attachment 3 Relationship with the case of the person making the amendment Patent applicant name FSK Co., Ltd. 4, Agent (zip code 141) Tokyo 25-4, Higashigotanda-chome, parts-use district] Voluntary amendment 7, Contents of the amendment 1) In the first line of page 4 of the specification, the phrase “what was made,” was replaced with “what was made.” ,” is corrected. 2) In the third line of page 28 of the same book, the phrase "perspective view of main parts showing the manufacturing process" is amended to "explanatory drawing showing the surface roughening process."

Claims (1)

[Scope of Claims] 1) A pressure-sensitive adhesive sheet for wafer bonding comprising an pressure-sensitive adhesive layer to which a semiconductor wafer is attached and a base material on the surface of which the pressure-sensitive adhesive layer is formed, wherein the back surface of the base material is roughened. An adhesive sheet for pasting wafers characterized by being treated. 2) The pressure-sensitive adhesive sheet according to claim 1, wherein the pressure-sensitive adhesive layer contains a pressure-sensitive adhesive and a radiation-polymerizable compound.