JP2016157859A - Wafer processing tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer processing tape capable of sufficiently suppressing generation of transfer marks onto an adhesive layer.SOLUTION: The wafer processing tape comprises: a release film; the adhesive layer which is provided on a surface of the release film and has a predetermined planar shape; and a viscous film including a label part that is provided in contact with the release film around the adhesive layer and has a predetermined planar shape, and a peripheral part which is provided to surround the outside of the label part. The adhesive layer includes an adhesive layer surface and an adhesive layer side edge that extends from the adhesive layer surface to the release film. The adhesive layer side edge is formed in such a manner that an angle between the adhesive layer surface and the adhesive layer side edge becomes abuse, that the adhesive layer side edge is inclined relatively to the release film and that an angle to the release film becomes 4.0 degrees or more and 84 degrees of less. Otherwise, the adhesive layer includes an adhesive layer surface and an adhesive layer side edge that extends from the adhesive layer surface to the release film while being smoothly curved.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wafer processing tape manufactured by precut processing, and more particularly to a wafer processing tape having a dicing die bonding film having two functions of a dicing tape and a die bonding film.

  Recently, a dicing tape for fixing a semiconductor wafer when the semiconductor wafer is cut and separated into individual chips (dicing) and a semiconductor chip that has been cut are bonded to a lead frame, a package substrate, or the like, or stacked. As a package, a dicing die bonding tape having two functions of a die bonding film (also referred to as a die attach film) for laminating and adhering semiconductor chips has been developed.

  Some dicing / die bonding tapes have been pre-cut in consideration of workability such as attachment to a wafer and attachment to a ring frame during dicing.

  Examples of the precut processed dicing die bonding film are shown in FIGS. FIGS. 4, 5A, and 5B are a schematic view, a plan view, and a cross-sectional view, respectively, of a wafer processing tape 30 provided with a dicing die bonding film 35. FIG. The wafer processing tape 30 includes a release film 31, an adhesive layer 32, and an adhesive film 33. The adhesive layer 32 is processed into a circle corresponding to the shape of the wafer, and has a circular label shape. The adhesive film 33 is obtained by removing the peripheral area of the circular portion corresponding to the shape of the ring frame for dicing. As shown in the drawing, the adhesive film 33 includes a circular label portion 33a and a peripheral portion 33b surrounding the outside. Have. The adhesive layer 32 and the circular label portion 33a of the pressure-sensitive adhesive film 33 are laminated with their centers aligned, and the circular label portion 33a of the pressure-sensitive adhesive film 33 covers the adhesive layer 32 and is released from the periphery thereof. It is in contact with the film 31. The dicing / die bonding film 35 is configured by a laminated structure including the adhesive layer 32 and the circular label portion 33 a of the adhesive film 33.

  When dicing the wafer, the release film 31 is peeled from the laminated adhesive layer 32 and the adhesive film 33, and the back surface of the semiconductor wafer W is pasted on the adhesive layer 32, as shown in FIG. The dicing ring frame R is adhesively fixed to the outer peripheral portion of the circular label portion 33 a of the adhesive film 33. In this state, the semiconductor wafer W is diced, and then the semiconductor chip is picked up. At this time, the semiconductor chip is picked up with the adhesive layer 32 attached to the back surface. The adhesive layer 32 attached to the back surface of the semiconductor chip then functions as a die bonding film when the semiconductor chip is bonded to a lead frame, a package substrate, or another semiconductor chip.

  By the way, as shown in FIGS. 4 and 5, the wafer processing tape 30 as described above is thicker in the portion where the adhesive layer 32 and the circular label portion 33a of the adhesive film 33 are laminated than the other portions. . In general, the angle between the surface of the adhesive layer 32 and the adhesive layer side edge 32a extending from the surface of the adhesive layer 32 to the release film 31 is formed at a right angle. For this reason, when wound as a product in a roll shape, the step between the laminated portion of the adhesive layer 32 and the circular label portion 33a of the pressure-sensitive adhesive film 33 and the peripheral portion 33a of the pressure-sensitive adhesive film 33 is overlapped, and a flexible adhesive A phenomenon in which a step is transferred to the surface of the layer 32, that is, a transfer mark (also referred to as a label mark, wrinkle, or winding mark) as shown in FIG. 7 occurs. When the transfer mark is generated, there is a risk that a defect may occur during the processing of the wafer due to poor adhesion between the adhesive layer and the semiconductor wafer.

  On the other hand, as a semiconductor device mounting method, flip chip mounting in which a semiconductor element is mounted on a circuit board by a face-down bonding method has been performed. Recently, it has been proposed to use a wafer processing tape for this flip chip mounting. Yes. In this case, since the adhesive layer is embedded in the bump electrode of the semiconductor element and the wiring step on the surface of the circuit board, a certain thickness is required. As the adhesive layer becomes thicker, the transfer marks resulting from the overlap of the steps become prominent.

  In order to suppress the occurrence of the transfer marks, it is conceivable to reduce the film winding pressure. However, in this method, the winding of the product occurs, for example, the film is difficult to set on the tape mounter. There is a risk of hindrance during actual use.

  Therefore, in order to suppress the occurrence of the label mark as described above, a film equal to or more than the total film thickness of the adhesive layer and the pressure-sensitive adhesive film on the outside of the adhesive layer and the pressure-sensitive adhesive film on the release substrate. An adhesive sheet provided with a support layer having a thickness is disclosed (for example, see Patent Document 1). The adhesive sheet of Patent Document 1 is provided with a support layer, so that the winding pressure applied to the adhesive sheet is dispersed or collected in the support layer to suppress the generation of transfer marks.

  Furthermore, in order to suppress the occurrence of label marks as described above, a pressure-sensitive adhesive film having an acute angle between the side edge of the label-like pressure-sensitive adhesive film or the peripheral edge of the pressure-sensitive adhesive film and the release film is disclosed. (For example, refer to Patent Document 2).

JP 2007-2173 A JP 2010-177401 A

  However, in the adhesive sheet of Patent Document 1, the adhesive layer and the pressure-sensitive adhesive film on the release substrate, the part other than the adhesive layer and the pressure-sensitive adhesive film required when manufacturing a semiconductor device, etc. Since the support layer is formed, the width of the support layer is limited, the width of the support layer is narrow relative to the outer diameter of the adhesive layer and the pressure-sensitive adhesive film, and the effect of suppressing the label mark is not sufficient. It was. Also, since the support layer is generally not sticky and does not adhere well to the release substrate (PET film), it floats from the release substrate at the narrowest part of the support layer, and is diced to the wafer. When the bonding film is bonded, the above-described floating portion is caught by the apparatus, causing a problem that the wafer is damaged.

  Although it is conceivable to increase the width of the support layer, the entire width of the wafer processing tape also increases, making it difficult to use existing equipment. In addition, since the support layer is a part that is finally discarded, increasing the width of the support layer leads to an increase in material cost.

  Moreover, although the adhesive film of the said patent document 2 can suppress the label trace derived from the label side edge part, it was not able to suppress the level | step difference trace derived from the level | step difference by the adhesive layer being thick.

  Accordingly, an object of the present invention is to provide a transfer mark on an adhesive layer when a wafer processing tape having a dicing die bonding film having an adhesive layer and an adhesive film is wound on a release film in a roll shape. An object of the present invention is to provide a wafer processing tape having a dicing die bonding film that can sufficiently suppress the occurrence of the above.

  In order to solve the above problems, a wafer processing tape according to the present invention comprises a release film, an adhesive layer having a predetermined planar shape provided on the surface of the release film, and the adhesive layer. A label portion having a predetermined planar shape that covers the adhesive layer and is in contact with the release film, and a peripheral portion that surrounds the label portion. A wafer processing tape including an adhesive film, wherein the adhesive layer has an adhesive layer surface and an adhesive layer side edge extending from the adhesive layer surface to the release film, and the bonding The agent layer side edge is formed such that the angle between the adhesive layer surface and the adhesive layer side edge is an obtuse angle and is inclined with respect to the release film, and the release film The angle with respect to 4.0 degrees or more and 84 degrees or less Characterized in that it is made.

  In the semiconductor processing tape, it is preferable that the adhesive layer side edge is formed at an angle of 45 degrees to 80 degrees with respect to the release film.

  In order to solve the above problems, a wafer processing tape according to the present invention includes a release film, an adhesive layer having a predetermined planar shape provided on the surface of the release film, and the adhesive. A label portion having a predetermined planar shape so as to cover the layer and come into contact with the release film around the adhesive layer, and a peripheral portion provided so as to surround the outside of the label portion A tape for processing a wafer including an adhesive film, wherein the adhesive layer has an adhesive layer surface and an adhesive layer side edge extending from the adhesive layer surface to the release film, The adhesive layer has an adhesive layer surface and an adhesive layer side edge portion that extends from the adhesive layer surface to the release film so as to be smoothly curved.

  According to the tape for wafer processing of the present invention, when the tape for wafer processing having an adhesive layer and an adhesive film is wound on a release film in a roll shape, the generation of transfer marks in the adhesive layer is sufficient. Can be suppressed.

(A) is a top view of the tape for wafer processing which concerns on 1st Embodiment, (B) is an AA sectional view. It is the L section enlarged view of FIG. (A) is the L section enlarged view in the tape for wafer processing which concerns on 2nd Embodiment, (B) is the modification. It is a schematic diagram of the conventional wafer processing tape. (A) is a top view of the conventional tape for wafer processing, (b) is BB sectional drawing. It is sectional drawing which shows the state by which the dicing die-bonding film and the ring frame for dicing were bonded together. It is a schematic diagram for demonstrating the malfunction of the conventional tape for wafer processing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a view for explaining a wafer processing tape according to the first embodiment. FIG. 1A is a plan view of the wafer processing tape according to the first embodiment, and FIG. It is AA sectional view taken on the line of FIG. FIG. 2 is a view for explaining an edge portion of the adhesive layer, and is an enlarged view of a portion L in FIG.
3A and 3B are views for explaining the edge portion of the adhesive layer side of the wafer processing tape according to the second embodiment. FIG. 3A is an enlarged view of the L portion, and FIG. It is.

<First Embodiment>
As shown in FIGS. 1 and 2, the wafer processing tape 10 according to the first embodiment includes a release film 11, an adhesive layer 12, and an adhesive film 13. The adhesive layer 12 is processed into a circle corresponding to the shape of the wafer, and has a circular label shape. The adhesive film 13 is obtained by removing the peripheral region of the circular portion corresponding to the shape of the ring frame for dicing. As shown in the drawing, the adhesive film 13 includes a circular label portion 13a and a peripheral portion 13b surrounding the outside. Have. The adhesive layer 12 and the circular label portion 13a of the pressure-sensitive adhesive film 13 are laminated with their centers aligned, and the circular label portion 13a of the pressure-sensitive adhesive film 13 covers the adhesive layer 12 and is released from the periphery thereof. It is in contact with the film 11. The dicing / die bonding film 15 is constituted by a laminated structure including the adhesive layer 12 and the circular label portion 13a of the adhesive film 13.

(Adhesive layer side edge)
And as the L section of the sectional view of the wafer processing tape (FIG. 1B) shows, the adhesive layer 12 is formed with an edge portion that is inclined with respect to the release film 11. Specifically, as illustrated in FIG. 2, the adhesive layer 12 includes an adhesive layer surface 12 a and an adhesive layer side edge 12 b extending from the adhesive layer surface 12 a to the release film 11. Here, the angle between the adhesive layer side edge 12 b and the adhesive layer surface 12 a is formed to be an obtuse angle, and the adhesive layer side edge 12 b is inclined with respect to the release film 11. Is formed.

  Therefore, according to the wafer processing tape 10 according to the first embodiment, the adhesive layer side edge 12b has an obtuse angle between the adhesive layer surface 12a and the adhesive layer side edge 12b. Since it is formed so as to be inclined with respect to the release film 11, when the wafer processing tape 10 is wound up in a roll shape, it is caused by a step in the label portion 13a caused by the presence of the adhesive layer 12. The pressure applied to the adhesive layer 12 can be dispersed. Therefore, when the wafer processing tape 10 is wound into a roll, the generation of transfer marks on the adhesive layer 12 can be sufficiently suppressed.

(Angle between the adhesive layer side edge and the release film)
With respect to the angle X between the adhesive layer side edge 12b and the release film 11, the adhesive layer side edge 12b is set to the release film 11 so that X is 4.0 degrees or more and 84 degrees or less. It is preferable to form.

  The smaller the angle X between the adhesive layer side edge 12b and the release film 11, the smaller the occurrence of transfer marks on the adhesive layer 12 when the wafer processing tape 10 is wound into a roll. There is an effect. However, if the angle X is too small, the thickness of the adhesive layer 12 in the region bonded to the wafer becomes thin. Therefore, when the wafer is bonded to the adhesive layer 12 and diced, the depth of cut changes depending on the position, so that dicing at a uniform depth becomes difficult.

  When the angle X is less than 4.0 degrees with respect to the wafer processing tape in which the thickness d of the adhesive layer 12 shown in FIG. 2 is 0.01 mm to 0.200 mm, uniform dicing becomes difficult. Is 4.0 degrees or more, the thickness of the adhesive layer 12 attached to the wafer is substantially constant, and uniform dicing can be performed.

  As a method of forming the adhesive layer side edge portion 12b, when punching the adhesive layer 12 into a circular shape of a predetermined size, a blade having a predetermined angle is used as a blade used for punching, and this blade is used as an adhesive. A method of forming the adhesive layer side edge portion 12b by pressing from the vertical direction against the layer surface 12a is preferably exemplified. Here, when the angle of the blade tip exceeds 45 degrees with respect to the vertical direction (pressing direction), it becomes difficult to insert the blade into the adhesive layer. (Direction) should be less than 45 degrees. Since the angle X between the adhesive layer side edge portion 12b punched with a blade having a tip end angle of less than 45 degrees and the release film 11 is 45 degrees or more, the adhesive layer side edge portion 12b And the release film 11 is preferably at an angle X of 45 degrees or more.

  The adhesive layer side edge portion 12b having an angle X of less than 45 degrees was punched using a blade having a tip portion angle of less than 45 degrees to form an adhesive layer side edge portion 12b having an angle X of 45 degrees or more. Then, the side edge part of the adhesive bond layer 12 can be produced by polishing or heat deformation.

  On the other hand, when the angle X exceeds 84 degrees, it approximates the angle (= 90 degrees) between the adhesive layer side edge 32a of the conventional wafer processing tape 30 and the release film 31, and the wafer processing tape is Since generation of transfer marks on the adhesive layer caused by winding in a roll cannot be suppressed, the angle X is preferably 84 degrees or less, and more preferably the angle X is 80 degrees or less. .

  Hereinafter, each component of the wafer processing tape according to the present embodiment will be described in detail.

(Release film)
As the release film 11 used for the wafer processing tape 10, a known film such as a polyethylene terephthalate (PET) type, a polyethylene type, or a film subjected to a release treatment can be used. The thickness of the release film is not particularly limited and may be appropriately set, but is preferably 25 to 50 μm.

(Adhesive layer)
The adhesive layer 12 is an adhesive for fixing a chip to a substrate or a lead frame by peeling off the adhesive film 13 and adhering to the chip when picking up the chip after the semiconductor wafer or the like is bonded and diced. It is used as Accordingly, the adhesive layer 12 has releasability capable of being peeled off from the adhesive film 13 while being attached to the separated semiconductor when picking up the chip, and further when die bonding is performed. In order to bond and fix the chip to the substrate or the lead frame, it must have sufficient bonding reliability.

  The adhesive layer 12 is obtained by forming a film of an adhesive in advance. For example, a known polyimide resin, polyamide resin, polyetherimide resin, polyamideimide resin, polyester resin, polyester resin, or polyesterimide used for the adhesive is used. Resin, phenoxy resin, polysulfone resin, polyethersulfone resin, polyphenylene sulfide resin, polyether ketone resin, chlorinated polypropylene resin, acrylic resin, polyurethane resin, epoxy resin, polyacrylamide resin, melamine resin, etc. Can do. Moreover, in order to reinforce the adhesive force with respect to a chip | tip or a lead frame, it is desirable to add a silane coupling agent or a titanium coupling agent to the said material and its mixture as an additive.

  The thickness of the adhesive layer 12 is not particularly limited, but is usually preferably about 5 to 200 μm. The adhesive layer 12 may be laminated on the entire surface of the pressure-sensitive adhesive film, but it is common to laminate an adhesive film that has been cut (pre-cut) into a shape corresponding to a wafer to be bonded in advance. When the adhesive film corresponding to the wafer is laminated, as shown in FIG. 6, the adhesive layer 12 is provided on the portion where the wafer W is bonded, and the adhesive layer is provided on the portion where the ring frame R for dicing is bonded. 12 and only the circular label portion 13a of the adhesive film 13 exists. In general, since the adhesive layer 12 is difficult to peel off from the adherend, the ring frame R can be bonded to the adhesive film 13 by using the pre-cut adhesive layer 12, and the ring is peeled off when the film is peeled off after use. The effect that the adhesive residue to the frame R hardly occurs is obtained.

(Adhesive film)
The adhesive film 13 has a sufficient adhesive strength so that the wafer does not peel when dicing the wafer, and has a low adhesive strength so that it can be easily peeled off from the adhesive layer 12 when picking up the chip after dicing. Is. For example, what provided the adhesive layer in the base film can be used conveniently.

  The base film of the adhesive film 13 can be used without particular limitation as long as it is a conventionally known base film. However, when a radiation curable material is used as the adhesive layer described later, the radiation transparency is used. It is preferable to use one having

  For example, as the material, polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic Α-olefin homopolymer or copolymer such as acid methyl copolymer, ethylene-acrylic acid copolymer, ionomer or a mixture thereof, polyurethane, styrene-ethylene-butene or pentene copolymer, polyamide-polyol Listed are thermoplastic elastomers such as copolymers, and mixtures thereof. Further, the base film may be a mixture of two or more materials selected from these groups, or may be a single layer or a multilayer. The thickness of the base film is not particularly limited and may be set as appropriate, but is preferably 50 to 200 μm.

  The resin used for the pressure-sensitive adhesive layer of the pressure-sensitive adhesive film 13 is not particularly limited, and a known chlorinated polypropylene resin, acrylic resin, polyester resin, polyurethane resin, epoxy resin, or the like used for the pressure-sensitive adhesive is used. can do.

  It is preferable to prepare a pressure-sensitive adhesive by appropriately mixing an acrylic pressure-sensitive adhesive, a radiation polymerizable compound, a photopolymerization initiator, a curing agent and the like with the resin of the pressure-sensitive adhesive layer. The thickness of the pressure-sensitive adhesive layer is not particularly limited and may be appropriately set, but is preferably 5 to 30 μm.

  A radiation-polymerizable compound can be blended in the pressure-sensitive adhesive layer to facilitate peeling from the adhesive layer by radiation curing. As the radiation polymerizable compound, for example, a low molecular weight compound having at least two photopolymerizable carbon-carbon double bonds in a molecule that can be three-dimensionally reticulated by light irradiation is used.

  Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene glycol diacrylate, 1,6 hexanediol diacrylate Acrylate, polyethylene glycol diacrylate, oligoester acrylate, and the like are applicable.

  In addition to the above acrylate compounds, urethane acrylate oligomers can also be used. The urethane acrylate oligomer includes a polyol compound such as a polyester type or a polyether type, and a polyvalent isocyanate compound (for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diene). A terminal isocyanate urethane prepolymer obtained by reacting isocyanate, 1,4-xylylene diisocyanate, diphenylmethane 4,4-diisocyanate, etc.) with an acrylate or methacrylate having a hydroxyl group (for example, 2-hydroxyethyl) Acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, polyethylene glycol acrylate, polyethylene glycol methacrylate, etc.) Obtained by the reaction. The pressure-sensitive adhesive layer may be a mixture of two or more selected from the above resins.

  When using a photopolymerization initiator, for example, isopropyl benzoin ether, isobutyl benzoin ether, benzophenone, Michler's ketone, chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, benzyldimethyl ketal, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethylphenyl Propane or the like can be used. The blending amount of these photopolymerization initiators is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the acrylic copolymer.

Second Embodiment
The wafer processing tape according to the second embodiment is a modification of the wafer processing tape according to the first embodiment having an edge portion in which the adhesive layer 12 is inclined with respect to the release film 11. As shown in FIG. 3A, the adhesive layer 22 has an adhesive layer side edge 25 that smoothly curves and extends from the adhesive layer surface 24 to the release film 21 with respect to the release film 21. The angle between the adhesive layer side edge 25 and the release film 21 is 90 degrees.

  FIG. 3B is a modification of the wafer processing tape according to the second embodiment. Similar to the wafer processing tape according to the second embodiment, it has an adhesive layer side edge 25 ′ extending in an arc shape from the adhesive layer surface 24 ′ to the release film 21. In the modification, it is formed so as to be very small at less than 90 degrees between the adhesive layer side edge portion 25 ′ and the release film 21.

  The arc shape of the adhesive layer side edge portions 25 and 25 ′ is such that the side edge portion of the adhesive layer that has been pre-cut into a rectangular shape in cross section like the conventional adhesive layer 32 is subjected to polishing or heat deformation. It can produce by applying.

  Therefore, according to the wafer processing tape 20 and its modification 20 ′ according to the second embodiment, the adhesive layer side edges 25, 25 ′ are smoothly formed on the release film 21 from the adhesive layer surfaces 24, 24 ′. Since the wafer processing tapes 20 and 20 'are wound in a roll shape, the pressure applied to the adhesive layer 22 due to the step in the label portion 23a caused by the presence of the adhesive layer 22 when the wafer processing tapes 20 and 20' are rolled up. Can be dispersed. Therefore, when the wafer processing tapes 20 and 20 ′ are wound up in a roll shape, generation of transfer marks on the adhesive layer 22 can be sufficiently suppressed.

  Next, examples of the present invention will be described, but the present invention is not limited to these examples.

A wafer processing tape was prepared as follows. First, after preparing the support base material (base film) and the pressure-sensitive adhesive composition 1, the pressure-sensitive adhesive composition was applied on the support base material so that the thickness after drying was 20 μm, at 110 ° C. An adhesive film was prepared by drying for 3 minutes. Next, an adhesive composition was prepared, and the adhesive composition was applied to a release film composed of a polyethylene-terephthalate film subjected to a release treatment so that the thickness after drying was 20 μm. It was made to dry for minutes and the adhesive film was created on the release film.
Then, the angle X between the adhesive layer side edge and the release film was changed within a certain range, and the adhesive film was cut into a circular label shape to form an adhesive layer. Further, after the adhesive film was cut into the shape shown in FIG. 4, the adhesive layer was bonded to the adhesive layer side of the adhesive film, and wafer processing tapes according to Examples and Comparative Examples were prepared. . The created wafer processing tape has a tape width of 290 mm, an adhesive layer diameter of 220 mm, a label portion diameter of 270 mm, and the center of the adhesive layer and label portion on the center line of the wafer processing tape. It formed so that it might overlap. Below, the preparation methods of a support base material, an adhesive composition, and an adhesive composition are shown.

(Preparation of support substrate)
Resin beads made of commercially available low density polyethylene (Novatec LL, manufactured by Nippon Polyethylene Co., Ltd.) were melted at 140 ° C. and formed into a long film having a thickness of 100 μm using an extruder.

(Preparation of adhesive composition)
First, the compound (0) having a radiation curable carbon-carbon double bond and a functional group is composed of 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate and methyl methacrylate, and has a mass average molecular weight of 700,000 and a glass transition temperature of -64 ° C. A copolymer compound having a radiation-curable carbon-carbon double bond content of 0.9 meq / g was prepared. To 100 parts by mass of this compound (0), 3 parts by mass of a polyisocyanate compound coronate L (manufactured by Nippon Polyurethane Co., Ltd., trade name) is added as a curing agent, and Irgacure 184 (manufactured by Ciba Geigy Japan) as a photopolymerization initiator (Trade name) By adding 5 parts by mass, a radiation-curable pressure-sensitive adhesive composition was obtained.

(Preparation of adhesive composition)
50 parts by weight of a cresol novolak type epoxy resin (epoxy equivalent 197, molecular weight 1200, softening point 70 ° C.) as an epoxy resin, 1.5 parts by weight of γ-mercaptopropyltrimethoxysilane as a silane coupling agent, γ-ureidopropyltriethoxysilane Cyclohexanone was added to a composition comprising 3 parts by mass and 30 parts by mass of silica filler having an average particle size of 16 nm, and the mixture was stirred and mixed, and further kneaded for 90 minutes using a bead mill.
To this, 100 parts by mass of acrylic resin (mass average molecular weight: 800,000, glass transition temperature: -17 ° C.), 5 parts by mass of dipentaerythritol hexaacrylate as a hexafunctional acrylate monomer, 0.5 adduct of hexamethylene diisocyanate as a curing agent Part by mass, 2.5 parts by mass of Curesol 2PZ (trade name, 2-phenylimidazole, manufactured by Shikoku Kasei Co., Ltd.) were added, stirred and mixed, and vacuum degassed to obtain an adhesive composition.

Example 1
The wafer processing tape has an angle X of 45 degrees between the adhesive layer side edge 12b and the release film 11.

(Example 2)
The wafer processing tape has an angle X between the adhesive layer side edge 12b and the release film 11 of 80 degrees.

(Example 3)
The wafer processing tape has an angle X of 84 degrees between the adhesive layer side edge 12b and the release film 11.

Example 4
The wafer processing tape has an angle X between the adhesive layer side edge portion 12b and the release film 11 of 90 degrees, and the adhesive layer 22 is released from the adhesive layer surface 24 with respect to the release film 21. This is a wafer processing tape having an adhesive layer side edge portion 25 that smoothly curves and extends on the film 21.

(Comparative Example 1)
The wafer processing tape has an angle X between the adhesive layer side edge 12b and the release film 11 of 90 degrees.

(Comparative Example 2)
The wafer processing tape has an angle X between the adhesive layer side edge portion 12b and the release film 11 of 85 degrees.

The inhibition of transfer marks was evaluated by the following evaluation method.
(Evaluation method of transfer mark suppression)
Using a winding core with an outer diameter of 76.2 mm, 300 wafer processing tapes with a width of 290 mm were wound at a constant tension of 15 N to prepare a roll body. And the roll body was refrigerated and stored in the environment of 5 degreeC for 30 days. Thereafter, the adhesive layer was visually observed to determine the presence or absence of wrinkles (transfer marks).

  Table 1 shows the evaluation results. In the table, ◯ indicates that no wrinkles were generated, x indicates that wrinkles were generated, and Δ indicates that wrinkles were not so large that air was drawn in at the time of wafer bonding.

  In Example 1 and Example 2, which are wafer processing tapes having an angle X between the adhesive layer side edge and the release film of 45 degrees or more and 80 degrees or less, generation of wrinkles was not confirmed. Further, in Example 3, which is a wafer processing tape having an angle X between the adhesive layer side edge and the release film of 84 degrees, although wrinkles were confirmed, air was blown during wafer bonding. It was not wrinkled enough to get involved. On the other hand, wrinkles occurred in Comparative Example 1 and Comparative Example 2, which were wafer processing tapes having an angle X between the adhesive layer side edge and the release film of 85 degrees or more.

  As mentioned above, according to the tape for wafer processing which concerns on this invention, with respect to a release film, an adhesive film side edge part becomes an obtuse angle between the adhesive layer surface and an adhesive layer side edge part. Therefore, when the wafer processing tape is wound into a roll, the generation of transfer marks on the adhesive layer can be sufficiently suppressed.

10, 20, 20 ′: Wafer processing tape 11: Release film 12, 22: Adhesive layer 13: Adhesive film 13a: Circular label portion 13b: Peripheral portions 12a, 24, 24 ′: Adhesive layer surfaces 12b, 25 25 ′: Adhesive layer side edge 15: Dicing die bonding film

Claims (3)

A release film,
An adhesive layer having a predetermined planar shape provided on the surface of the release film;
A label portion having a predetermined planar shape that covers the adhesive layer and is in contact with the release film around the adhesive layer, and is provided so as to surround an outer side of the label portion. A wafer processing tape including an adhesive film having a peripheral portion,
The adhesive layer has an adhesive layer surface and an adhesive layer side edge extending from the adhesive layer surface to the release film,
The adhesive layer side edge is formed such that an angle between the adhesive layer surface and the adhesive layer side edge is an obtuse angle and is inclined with respect to the release film, and the release layer A wafer processing tape having an angle with respect to a mold film of 4.0 degrees or more and 84 degrees or less.   2. The upper processing tape according to claim 1, wherein the adhesive layer side edge is formed with an angle of 45 degrees or more and 80 degrees or less with respect to the release film. A release film,
An adhesive layer having a predetermined planar shape provided on the surface of the release film;
A label portion having a predetermined planar shape that covers the adhesive layer and is in contact with the release film around the adhesive layer, and is provided so as to surround an outer side of the label portion. A wafer processing tape including an adhesive film having a peripheral portion,
The adhesive layer has an adhesive layer surface and an adhesive layer side edge extending from the adhesive layer surface to the release film,
The tape for wafer processing, wherein the adhesive layer has an adhesive layer surface and an adhesive layer side edge extending smoothly curved from the adhesive layer surface to the release film.

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