JP5408571B2 - Wafer processing tape and manufacturing method thereof - Google Patents

Description

  The present invention relates to a wafer processing tape and a method for manufacturing the same. In particular, the present invention relates to a wafer processing tape having an adhesive film and an adhesive layer provided on the adhesive film, and a method for producing the same.

  In recent years, in order to fix a semiconductor wafer when the semiconductor wafer is cut and separated (diced) into individual chips, a wafer processing tape in which an adhesive layer is provided on a base film has been developed. In addition, an adhesive layer is further laminated on the adhesive layer in order to bond the cut semiconductor chip to a lead frame, a package substrate, etc., or to stack and bond the semiconductor chips together in a stacked package. A wafer processing tape (dicing die bonding film) having a structure has also been developed (see, for example, Patent Document 1).

  As such a wafer processing tape (dicing die bonding film), a tape that has been pre-cut processed in consideration of workability such as attachment to a semiconductor wafer and attachment to a ring frame during dicing. Yes (see, for example, Patent Document 2).

  The manufacturing process of the wafer processing tape (dicing die bonding film) subjected to the pre-cut processing is a first cut of a predetermined shape (for example, a circle) in the adhesive layer of the adhesive film composed of the release film and the adhesive layer. An unnecessary adhesive layer portion outside the first cut is peeled off from the release film, and an adhesive film having a predetermined shape on the release film, an adhesive layer and a base A primary pre-cutting step in which an adhesive film made of a material film is bonded so that the adhesive layer and the adhesive layer are in contact with each other, and a predetermined shape (for example, a circle) of a first shape surrounding the adhesive film around the shape of the adhesive layer Make two cuts, peel off the unnecessary adhesive film part outside the second cut from the adhesive film (release film), wind it up, and place it on the adhesive film (release film). And adhesive film of the secondary pre-cut processing for forming a step shape, and a.

  In the production of the wafer processing tape as described above, a production method (first method) for producing a wafer processing tape by successively performing the above-described two steps (primary precut processing step and secondary precut processing step). Production method) or by making a first cut of a predetermined shape (for example, a circle) in the adhesive layer, and peeling off the unnecessary adhesive layer portion outside the first cut from the release film. Adhesion with a primary pre-cutting process in which an adhesive film having an adhesive layer of a predetermined shape formed thereon, an adhesive film composed of an adhesive layer and a base film are bonded together so that the adhesive layer and the adhesive layer are in contact with each other A production method for producing a wafer processing tape by winding a film into a roll, and then recognizing and aligning the position of the adhesive layer and performing a secondary pre-cut processing step ( 2 of the manufacturing method) there is.

  In addition, semiconductor devices are becoming finer and thinner in response to higher speed, lower power consumption, and smaller size of semiconductor devices. Accordingly, the number of stacked semiconductor chips has been increased, and a wafer processing tape used for manufacturing a semiconductor device has a thinner (less than 10 μm) adhesive layer than conventional wafer processing tapes. The demand for tape is increasing.

  In the above-described demand, when performing the secondary precut processing, the first manufacturing method described above can be applied to the adhesive film at a predetermined interval without recognizing the position of the primary precut processing adhesive layer. In contrast to making the second cut, in the second manufacturing method described above, after recognizing the position of the adhesive layer subjected to the primary precut process, the second cut is made in the adhesive film in accordance with the position of the adhesive layer. Therefore, in the conventional wafer processing tape in which the base film, the pressure-sensitive adhesive layer, and the adhesive layer are laminated in this order as proposed in Patent Document 1 and Patent Document 2, the adhesive layer is made thin. In the second manufacturing method described above, the outer peripheral portion of the primary pre-cut adhesive layer is recognized by an optical sensor (for example, a transmissive sensor or a reflective sensor). A problem that the lowering of the label recognition of that can not be had occurred. Therefore, when performing pre-cut processing (secondary pre-cut processing) of an adhesive film composed of a base film and an adhesive layer, for example, the productivity may be reduced such that the pre-cut blade does not operate or the adhesive layer There has been a problem in that the accuracy of inspection is reduced such that the presence or absence of the shape and the shape inspection cannot be performed.

  In order to solve such a problem of sensor recognizability degradation, an optical sensor is used as a primary pre-cut by using an adhesive layer containing a pigment that absorbs or reflects light within a wavelength range in which the optical sensor reacts. An adhesive sheet (adhesive film) for recognizing the outer peripheral portion of the processed adhesive layer has also been developed (see, for example, Patent Document 3).

JP 2005-303275 A JP 2006-111727 A JP 2009-059917 A

  However, in the adhesive film proposed in Patent Document 3 and the wafer processing tape using this adhesive film, since the adhesive layer contains a pigment, the adhesiveness of the adhesive layer is lowered, and the adhesive film and the adhesive film are bonded. There has been a new problem that the reliability of the wafer processing tape using the film is lowered.

  Therefore, the present invention has been made to solve the above-described problems, and the sensor recognizability is good even when the adhesive layer is thin (10 μm or less, particularly 5 μm or less). An object of the present invention is to provide a wafer processing tape having good productivity and inspection accuracy and a method for manufacturing the same.

  As a result of intensive studies on the above problems, the inventors of the present invention have released a mold release film, an adhesive layer, and a wafer processing tape in which an adhesive film has been laminated in this order when the adhesive layer is first precut. The notch part formed on the surface of the film is located at a position corresponding to the position where the notch part is located in the laminated part where the release film and the adhesive film are laminated, at a position where there is no notch part and the transmittance A of 600 to 700 nm wavelength. By forming the corresponding portion so that the transmittance difference C (= A−B) with the transmittance B of 600 to 700 nm wavelength is 0.1% or more, the adhesive layer is thin (less than 10 μm, Even in the case of 5 μm or less in particular, the present inventors have found that the sensor recognizability, productivity, and inspection accuracy are good and completed the present invention.

  That is, the wafer processing tape according to the first aspect of the present invention includes a long release film, one or more adhesive layers having a predetermined planar shape provided on the release film, One or more pressure-sensitive adhesive films each covering an adhesive layer and provided so as to be in contact with the release film around the adhesive layer, the release film, The surface of the release film on which the adhesive layer is laminated is formed with an annular cut along the outer periphery of the adhesive layer, and the release film and the adhesive film are laminated. In the laminated portion, transmission between the transmittance A of 600 to 700 nm wavelength of the laminated portion corresponding to the position where the cut portion is present and the transmittance B of 600 to 700 nm wavelength of the laminated portion corresponding to the position where the cut portion is not present. rate C (= A-B), characterized in that at least 0.1%.

  The wafer processing tape according to the second aspect of the present invention is the wafer processing tape according to the first aspect of the present invention, wherein the transmittance difference C is 0.6 to 1.3%. .

  The wafer processing tape according to the third aspect of the present invention is characterized in that the transmittance A is 75 to 95% in the wafer processing tape according to the first or second aspect of the present invention.

  A wafer processing tape according to a fourth aspect of the present invention is the wafer processing tape according to any one of the first to third aspects of the present invention, and surrounds the outside of the adhesive film on the release film. It is provided with the peripheral part which consists of the said adhesive film and was provided.

  In the method for producing a wafer processing tape according to the first aspect of the present invention, (a) a plurality of adhesive layers having a predetermined planar shape are provided on a long release film, and the release film and Laminating an adhesive film on the adhesive film in which the adhesive layer is laminated in this order, covering the adhesive layer, and contacting the release film around the adhesive layer; and (B) In the laminate composed of the adhesive film and the pressure-sensitive adhesive film formed by the step (a), the laminate portion composed of the release film and the pressure-sensitive adhesive film is moved from the surface of the pressure-sensitive adhesive film. Forming a plurality of annular second notches surrounding each of the adhesive layers until reaching the release film, a method for producing a wafer processing tape comprising the step (a) (C) when providing a plurality of the adhesive layers having a predetermined planar shape on the release film, the annular first cut portion along the outer periphery of the adhesive layer A step of forming the film on a film, wherein the step (b) includes a step of 600 to 700 nm of the laminated portion corresponding to a position where the cut portion is present in the laminated portion in which the release film and the adhesive film are laminated. Based on the transmittance A of the wavelength and the transmittance difference C (= A−B) between the laminated film and the transmittance B of the wavelength of 600 to 700 nm corresponding to the position where the release film and the cut portion do not exist. One notch is recognized, and an annular second notch surrounding the adhesive layer is formed based on the recognized first notch.

  The method for producing a wafer processing tape according to the second aspect of the present invention is the method for producing a wafer processing tape according to the first aspect of the present invention, wherein the step (c) is such that the transmittance difference C is 0. The first cut portion is formed so as to be 1% or more.

  The method for manufacturing a wafer processing tape according to a third aspect of the present invention is the method for manufacturing a wafer processing tape according to the first aspect of the present invention, wherein the step (c) is such that the transmittance difference C is 0. The first cut portion is formed so as to be 6 to 1.3%.

  A wafer processing tape manufacturing method according to a fourth aspect of the present invention is the wafer processing tape manufacturing method according to any one of the first to third aspects of the present invention, in place of the step (b). (D) In the laminate composed of the adhesive film and the pressure-sensitive adhesive film formed in the step (a), the pressure-sensitive adhesive film is formed on the laminated portion including the release film and the pressure-sensitive adhesive film. Forming a plurality of annular second notches surrounding each adhesive layer from the surface to the release film, and forming a third notch outside the second notches It is characterized by comprising a forming step.

  According to the wafer processing tape of the present invention, the sensor recognizability can be improved even when the adhesive layer is thin (10 μm or less, particularly 5 μm or less). Therefore, in the semiconductor device manufacturing process, the use of the wafer processing tape of the present invention reduces the productivity of the semiconductor device even when the adhesive layer is thin (less than 10 μm, particularly less than 5 μm). And a decrease in inspection accuracy can be prevented.

(A) is a general-view figure of the wafer processing tape 10 which concerns on one Embodiment of this invention, (b) is the same top view, (c) is the same sectional drawing. It is a general-view figure of the tape for wafer processing 10a which is a modification of the tape for wafer processing which concerns on the 1st Embodiment of this invention. It is a general-view figure of the tape 10b for wafer processing which is a modification of the tape for wafer processing which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the tape 10 for wafer processing of FIG. FIG. 5 is a view subsequent to FIG. 4 for explaining a method of manufacturing the wafer processing tape 10 of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1A is a perspective view of a wafer processing tape 10 according to an embodiment of the present invention, FIG. 1B is a plan view thereof, and FIG. 1C is a sectional view thereof.

  As shown in FIGS. 1A, 1B, and 1C, the wafer processing tape 10 includes a long release film 11, an adhesive layer 12 (22), and an adhesive film 13 (23a, 23b). ). The wafer processing tape 10 constitutes a dicing die bonding film 20 composed of an adhesive layer 12 (22) and an adhesive film 13 (23a).

  The adhesive layer 12 is provided on the surface 11a of the release film 11, and has a label shape corresponding to the shape of the semiconductor wafer. Here, a circular shape will be described as an example of the label shape, but the label shape is not limited to the circular shape. Hereinafter, the label-shaped adhesive layer 12 is referred to as a label-shaped adhesive portion 22.

  In the release film 11, an annular first cut portion (hereinafter referred to as a first cut portion) 26 is formed on the surface 11 a along the outer periphery of the label-shaped adhesive portion 22.

  The adhesive film 13 includes a label part 23a and a peripheral part 23b. The label part 23 a covers the label-shaped adhesive part 22 and is provided so as to come into contact with the release film 11 around the label-shaped adhesive part 22. The label portion 23a has a substantially circular shape corresponding to the dicing ring frame. The peripheral portion 23b does not completely surround the outside of the label portion 23a, and is provided so that the exposed release film 11 between the label portion 23a and the peripheral portion 23b is continuous.

  In the wafer processing tape 10 shown in FIG. 1, the peripheral portion 23b is provided so that the exposed release film 11 between the label portion 23a and the peripheral portion 23b is continuous. As shown, the peripheral portion 23b is a wafer processing tape 10a provided so as to completely surround the outside of the label portion 23a and the exposed release film 11 surrounding the outer periphery of the label portion 23a to be discontinuous. May be. Moreover, as shown in FIG. 3, the peripheral part 23b may not exist, and the tape 10b for wafer processing by which the adhesive film 13 was comprised only by the label part 23a may be sufficient.

  Hereafter, each component of the tape 10 for wafer processing of this embodiment mentioned above is demonstrated in detail.

(Release film)
The release film 11 is used for the purpose of improving the handleability of the adhesive layer 12. In the release film 11, an annular first cut portion 26 is formed on the surface 11 a along the outer periphery of the label-shaped adhesive portion 22.

  Examples of the release film 11 include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polychloride chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, a polyethylene naphthalate film, and a polybutylene terephthalate film. , Polyurethane film, ethylene / vinyl acetate copolymer film, ionomer resin film, ethylene / (meth) acrylic acid copolymer film, ethylene / (meth) acrylic acid ester copolymer film, polystyrene film, polycarbonate film, polyimide film A fluororesin film or the like is used. These crosslinked films are also used. Furthermore, these laminated films may be sufficient.

The surface tension of the release film 11 is preferably 40 mN / m or less, and more preferably 35 mN / m or less. Such a release film 11 having a low surface tension can be obtained by appropriately selecting the material, and can also be obtained by applying a release treatment by applying a silicone resin or the like to the surface of the film. .
The film thickness of the release film 11 is usually 5 to 300 μm, preferably 10 to 200 μm, and particularly preferably about 20 to 150 μm.

The first cut portion 26 formed on the surface 11a of the release film 11 is a laminate portion 27b having the first cut portion 26 in the laminate portion where the release film 11 and the adhesive film 13 (23a) are laminated. The transmittance difference C (= A−B) between the transmittance A (%) at a wavelength of ˜700 nm and the transmittance B (%) at a wavelength of 600 to 700 nm of the laminated portion 27a without the first notch 26 is 0.1. % Or more. More preferably, the first cut portion 26 is formed such that the transmittance difference C is 0.6 to 1.3%.
This is because sufficient sensor recognizability cannot be obtained when the transmittance difference C is less than 0.1%.

  Further, it is more preferable that the transmittance A is 75 to 95%. This is because sufficient sensor recognition cannot be obtained when the transmittance A is less than 75% or more than 95%.

  As will be described later, in the adhesive film 13 in which the adhesive layer is provided on the base film, the transmittance B is determined by the type and thickness of the base film, and the transmittance difference C is determined by the depth of cut. Whether the depth is 0.1% or more depends on the type and thickness of the base film. More specifically, the transmittance of the base film is higher as it is more transparent in appearance, and the transmittance is lower as it is colored. Further, even with the release film 11 made of the same material, the adhesive film 13 having an adhesive applied to the embossed surface has a high transmittance, and the adhesive film 13 having an adhesive applied to the mirror surface has a low transmittance. Moreover, the transmittance | permeability is so low that a base film is thick. And in order to make the transmittance | permeability difference C 0.1% or more, it is necessary to cut deeply with respect to the release film 11, so that the transmittance | permeability B is high. Therefore, when the ratio of the depth of the 1st cut part 26 with respect to the total thickness of the release film 11 is set to D, it is good to form the 1st cut part 26 so that the ratio D may be 13 to 92%.

  Here, if the ratio D is less than 13%, the manufacturability becomes unstable. Moreover, it is because sufficient sensor recognizability cannot be obtained. It should be noted that the manufacturability is unstable when the adhesive layer 12 is primarily precut to form the label-shaped adhesive portion 22 and the primary precut is insufficient, and an unnecessary adhesive layer other than the label-shaped adhesive portion 22 is used. This means that when the portion 12 is rolled up, the wafer processing tape 10 may not be manufactured due to the winding up to the portion of the label-shaped adhesive portion 22.

  Further, when the ratio D is larger than 92%, good sensor recognizability can be obtained. However, the wafer processing tape 10 for manufacturing the wafer processing tape 10 after the primary precut or the semiconductor device is used. This is because the release film 11 is broken in the work process and various problems occur. For example, in each winding process (slit, secondary precut) of manufacturing the wafer processing tape 10 after the primary precut, due to a slit defect that must be reconditioned due to a width dimension shift, or due to breakage of the release film 11 In order to become a short product, a winding trouble that requires repeated splicing and reconditioning occurs. For example, when a breakage occurs in the bonding process between the semiconductor wafer and the dicing die bonding film 20 in the manufacture of the semiconductor device, the release film 11 is wound and bonded between the semiconductor wafer and the dicing die bonding film 20. Since the fully automatic device is stopped due to the failure, a reworking operation becomes necessary.

(Adhesive layer)
The adhesive layer 12 is attached to the back surface of the semiconductor chip when the semiconductor chip is picked up after the semiconductor wafer is bonded and diced, and is used as an adhesive for fixing the chip to the substrate or the lead frame. It is what is done.

  As the adhesive layer 12, polyimide resin, polyamide resin, polyetherimide resin, polyamideimide resin, polyester resin, polyester resin, polyesterimide resin, phenoxy resin, polysulfone resin, polyethersulfone resin, polyphenylene sulfide resin, polyetherketone Resins, chlorinated polypropylene resins, acrylic resins, polyurethane resins, epoxy resins, polyacrylamide resins, melamine resins, and the like, and mixtures thereof can be used.

  It is preferable to use an epoxy group-containing acrylic copolymer as the polymer. This epoxy group-containing acrylic copolymer contains 0.5 to 6% by mass of glycidyl acrylate or glycidyl methacrylate having an epoxy group. In order to obtain a high adhesive force with a semiconductor wafer, the content is preferably 0.5% by mass or more, and gelation can be suppressed if it is 6% by mass or less. The glass transition temperature (Tg) of the epoxy group-containing acrylic copolymer is preferably −10 ° C. or higher and 30 ° C. or lower.

  The amount of glycidyl acrylate or glycidyl methacrylate used as the functional group monomer is a copolymer ratio of 0.5 to 6% by mass, but the remainder is an alkyl having 1 to 8 carbon atoms such as methyl acrylate and methyl methacrylate. Mixtures of acrylates, alkyl methacrylates, and styrene and acrylonitrile can be used. Among these, ethyl (meth) acrylate and / or butyl (meth) acrylate are particularly preferable. The mixing ratio is preferably adjusted in consideration of the glass transition temperature (Tg) of the copolymer. There is no restriction | limiting in particular in a polymerization method, For example, pearl polymerization, solution polymerization, etc. are mentioned, A copolymer is obtained by these methods. Examples of such an epoxy group-containing acrylic copolymer include HTR-860P-3 (trade name, manufactured by Nagase ChemteX Corporation).

  The weight average molecular weight of the acrylic copolymer is preferably 50,000 or more, particularly preferably in the range of 200,000 to 1,000,000. If the molecular weight is too low, film formation will be insufficient, and if it is too high, compatibility with other components will deteriorate, resulting in hindering film formation.

  When an epoxy resin is used as the thermosetting component, for example, a phenolic resin can be used as the curing agent. As the phenolic resin, a condensate of phenols such as alkylphenol, polyhydric phenol, naphthol and aldehydes is used without particular limitation. The phenolic hydroxyl group contained in these phenolic resins can easily undergo an addition reaction with the epoxy group of the epoxy resin by heating to form a cured product having high impact resistance.

  Phenol resins include phenol novolak resin, o-cresol novolak resin, p-cresol novolak resin, t-butylphenol novolak resin, dicyclopentadiene cresol resin, polyparavinylphenol resin, bisphenol A type novolak resin, or modifications thereof. A thing etc. are used preferably.

  In addition, a thermally activated latent epoxy resin curing agent can also be used as the curing agent. This curing agent is a type of curing agent that does not react with the epoxy resin at room temperature but is activated by heating at a certain temperature or more and reacts with the epoxy resin.

  As an activation method, a method of generating active species (anions and cations) by a chemical reaction by heating, a dispersion that is stably dispersed in the epoxy resin near room temperature, is compatible with and dissolved in the epoxy resin at a high temperature, and a curing reaction is performed. There are a method for starting, a method for starting a curing reaction by elution at a high temperature with a molecular sieve encapsulated type curing agent, a method using a microcapsule, and the like.

  Examples of the thermally active latent epoxy resin curing agent include various onium salts, high melting point active hydrogen compounds such as dibasic acid dihydrazide compounds, dicyandiamide, amine adduct curing agents, and imidazole compounds.

  When an epoxy resin is used as the thermosetting component, a curing accelerator or the like can be used as an auxiliary agent. There is no restriction | limiting in particular as a hardening accelerator which can be used for this invention, For example, a tertiary amine, imidazoles, a quaternary ammonium salt etc. can be used. Examples of imidazoles preferably used in the present invention include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, and the like. These may be used alone or in combination of two or more. Imidazoles are commercially available from Shikoku Kasei Kogyo Co., Ltd. under the trade names 2E4MZ, 2PZ-CN, 2PZ-CNS, for example.

  Moreover, you may mix | blend a filler. Examples of the filler include silica such as crystalline silica and synthetic silica, and inorganic filler such as alumina and glass balloon. By adding an inorganic filler to the curable protective film forming layer 2, the hardness of the protective film after curing can be improved. Moreover, the thermal expansion coefficient of the protective film after curing can be brought close to the thermal expansion coefficient of the wafer, thereby reducing the warpage of the semiconductor wafer during processing. Synthetic silica is preferable as the filler, and in particular, synthetic silica of the type from which the α-ray source that causes malfunction of the semiconductor device is removed as much as possible is optimal. As the shape of the filler, any of a spherical shape, a needle shape, and an amorphous type can be used, but a spherical filler capable of closest packing is particularly preferable.

  Furthermore, in order to improve the interfacial bonding between different materials, a coupling agent can be blended. A silane coupling agent is preferable as the coupling agent. As the silane coupling agent, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β-aminoethyl-γ- Examples include aminopropyltrimethoxysilane. The blending amount of the coupling agent is preferably 0.1 to 10 parts by weight with respect to a total of 100 parts by weight of the composition forming each of the dispersed phase and the continuous phase, from the effects of addition, heat resistance and cost. .

As the varnishing solvent, it is preferable to use methyl ethyl ketone, acetone, methyl isobutyl ketone, 2-ethoxyethanol, toluene, butyl cellosolve, methanol, ethanol, 2-methoxyethanol or the like having a relatively low boiling point. Moreover, you may add a high boiling point solvent for the purpose of improving coating-film property. Examples of the high boiling point solvent include dimethylacetamide, dimethylformamide, methylpyrrolidone, cyclohexanone and the like.
The thickness of the adhesive layer 12 may be set as appropriate, but is preferably about 5 to 100 μm.

  In order to increase the breaking strength of the adhesive layer 12, it is effective to increase the polymer, decrease the filler, and decrease the epoxy resin (solid). Further, in order to reduce the peeling force of the adhesive layer 12 from the release film 11, it is effective to reduce the polymer and the epoxy resin (liquid).

(Adhesive film)
The adhesive film 13 is not particularly limited, and has a sufficient adhesive force so that the semiconductor wafer does not peel when dicing the semiconductor wafer. When the chip is picked up after dicing, it can be easily removed from the adhesive layer 12. Any material may be used as long as it exhibits low adhesive strength so that it can be peeled off. 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 12 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.

  The wafer processing tape 10 (10a, 10b) according to one embodiment of the present invention described above is formed by the first cut portion 26 even when the adhesive layer 12 is thin (less than 10 μm, particularly not more than 5 μm). The outer peripheral portion of the adhesive layer 12 (label-shaped adhesive portion 22) can be recognized by the sensor. That is, the wafer processing tape 10 (10a, 10b) according to one embodiment of the present invention described above has sensor recognizability even when the adhesive layer 12 is thin (10 μm or less, particularly 5 μm or less). Can be good. Therefore, in the manufacturing process of the semiconductor device, when the adhesive layer 12 is thin (10 μm or less, particularly 5 μm or less) by using the wafer processing tape 10 (10a, 10b) according to one embodiment of the present invention. Even when the adhesive film 13 is precut, for example, the productivity is prevented from being lowered, for example, the precut blade is not operated, and the presence or absence of the adhesive layer and the inspection accuracy from being unable to be inspected are prevented. be able to.

Next, the wafer processing tape according to one embodiment of the present invention for manufacturing the wafer processing tape 10 according to one embodiment of the present invention shown in FIGS. 1 (a), (b) and (c) is shown. A manufacturing method will be described.
4 and 5 are views for explaining a method for manufacturing a wafer processing tape according to an embodiment of the present invention for manufacturing the wafer processing tape 10 of the present invention.

  As shown in FIG. 4, first, the surface of the adhesive layer 12 is formed on the first laminate 25 in which the adhesive layer 12 is laminated on the long release film 11 using a precut blade (not shown). An annular first cut portion 26 from 12a to the release film 11 is formed (step 1: S1). Here, a punching process may be performed so as to form the first cut portion 26 using a mold instead of the precut blade.

  At this time, the first cut portion 26 is a laminated portion 27b having the first cut portion 26 in the laminated portion in which the release film 11 and the adhesive film 13 (23a) formed in Steps 3 to 5 described later are laminated. The transmittance difference C between the transmittance A having a wavelength of 600 to 700 nm and the transmittance B having a wavelength of 600 to 700 nm of the stacked portion 27a without the first cut portion 26 is 0.1% or more. Preferably, the first cut portion 26 is formed so that the transmittance difference C is 0.6 to 1.3%. Further, it is more preferable that the transmittance A is 75 to 95%.

  In order to set the transmittance difference C to 0.1% or more, when the ratio of the depth of the first cut portion 26 to the total thickness of the release film 11 is D, the ratio D is 13 to 92%. It is good to form so that it becomes. The transmittance B is determined by the type and thickness of the substrate film, and the transmittance difference C is determined by the depth of cut. How much the depth of cut is 0.1% or more depends on the type and thickness of the substrate film. It depends on the size. More specifically, the transmittance B of the base film is higher as it is more transparent in appearance, and the transmittance is lower as it is colored. Further, even with the release film 11 made of the same material, the adhesive film 13 having an adhesive applied to the embossed surface has a high transmittance, and the adhesive film 13 having an adhesive applied to the mirror surface has a low transmittance. Moreover, the transmittance | permeability is so low that a base film is thick. Therefore, in order to set the transmittance difference C to 0.1% or more, it is necessary to cut deeper into the release film 11 as the transmittance B is higher.

  Next, the unnecessary adhesive layer 12 outside the first cut portion 26 is removed by peeling from the release film 11, and only the label-shaped adhesive portion 22, which is the label-shaped adhesive layer 12, is placed on the release film 11. (Step 2: S2).

  Next, the 2nd laminated body 27 which laminated | stacked the adhesive film 13 is formed so that the whole surface of the label-shaped adhesion part 22 and the exposed release film 11 may be covered (step 3: S3).

  Next, as shown in FIG. 5, from the surface 13 a of the adhesive film 13, a pre-cut blade (not shown) is used for the laminated portion 27 c composed of the release film 11 and the adhesive film 13 of the second laminate 27. An annular second cut portion 28 surrounding the label-shaped adhesive portion 22 until reaching the release film 11, and a third cut portion 29 that does not completely surround the second cut portion 28 outside the second cut portion 28. (Step 4: S4).

  When the second cut portion 28 is formed, in the laminated portion 27c where the release film 11 and the adhesive film 13 are laminated, the wavelength of 600 to 700 nm of the laminated portion 27b corresponding to the position where the first cut portion 26 is located. Based on the transmittance difference C (= A−B) between the transmittance A and the transmittance B of 600 to 700 nm wavelength of the laminated portion 27a corresponding to the position where the first notch portion 26 is not present, the first notch portion 26 is recognized. Then, based on the recognized first cut portion 26, an annular second cut portion 28 surrounding the label-shaped adhesive portion 22 is formed.

  Here, a punching process may be performed so as to form the second cut portion 28 and the third cut portion 29 using a mold instead of the precut blade. Moreover, although the formation of the second cut portion 28 and the formation of the third cut portion 29 are performed simultaneously, they may be formed separately. At that time, either may be formed first. In the case where the peripheral portion 23b as shown in the wafer processing tape 10a (see FIG. 2) completely surrounds the outside of the label portion 23a, the third cut portion 29 is formed in an annular shape surrounding the second cut portion 28. It forms so that it may become a notch part. In the case where there is no peripheral portion 23b as shown in the wafer processing tape 10b (see FIG. 3), the third cut portion 29 is not formed, and only the second cut portion 28 is formed.

  Next, the unnecessary adhesive film 13 between the second cut portion 28 and the third cut portion 29 is peeled off from the release film 11 to be removed, thereby forming a label portion 23a and a peripheral portion 23b made of the adhesive film 13 ( Step 5: S5). Thus, the wafer processing tape 10 having the dicing die bonding film 20 including the label-shaped adhesive portion 22 and the label portion 23a, that is, the adhesive layer 12 and the adhesive film 13, is formed.

  When the wafer processing tape 10b (see FIG. 3) does not have the peripheral portion 23b, the unnecessary adhesive film 13 outside the second cut portion 28 is peeled off from the release film 11 and removed. Then, only the label portion 23a made of the adhesive film 13 is formed.

(Example)
Next, examples of the present invention will be described, but the present invention is not limited to these examples.
(Formation of adhesive layer)
50 parts by mass of a cresol novolac type epoxy resin (epoxy equivalent 197, molecular weight 1200, softening point 70 ° C.) as an epoxy resin, 1.5 parts by mass of γ-mercaptopropyltrimethoxysilane as a silane coupling agent, γ-ureidopropyltriethoxysilane Cyclohexanone was added to a composition consisting of 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 mass of adduct of hexamethylene diisocyanate as a curing agent Part, Curesol 2PZ (trade name, 2-phenylimidazole, manufactured by Shikoku Kasei Co., Ltd.) 2.5 parts by mass, stirred and mixed, vacuum degassed to obtain an adhesive.

  The above adhesive is applied onto a release film having a thickness of 38 μm and dried by heating at 110 ° C. for 1 minute to form a coating film in a B-stage state (curing intermediate state of thermosetting resin) having a thickness of 5 μm. An adhesive layer was formed on the release film and stored refrigerated.

(Formation of adhesive film)
In 400 g of toluene as a solvent, 128 g of n-butyl acrylate, 307 g of 2-ethylhexyl acrylate, 67 g of methyl methacrylate, 1.5 g of methacrylic acid, and a mixed solution of benzoyl peroxide as a polymerization initiator are appropriately adjusted in a dropping amount, and reacted. The temperature and the reaction time were adjusted to obtain a solution of the compound (1) having a functional group.

  Next, 2.5 g of 2-hydroxyethyl methacrylate synthesized separately from methacrylic acid and ethylene glycol as a compound (2) having a radiation curable carbon-carbon double bond and a functional group was added to this polymer solution, and hydroquinone as a polymerization inhibitor. Was added by appropriately adjusting the dropping amount, and the reaction temperature and reaction time were adjusted to obtain a solution of the compound (A) having a radiation curable carbon-carbon double bond. Subsequently, 100 parts by mass of the compound (A) in the compound (A) solution was added by 1 part by mass of Nippon Polyurethane Co., Ltd .: Coronate L as a polyisocyanate (B), and manufactured by Ciba Geigy of Japan: Iruga as a photopolymerization initiator. A radiation curable pressure-sensitive adhesive composition was prepared by adding 0.5 parts by mass of Cure 184 and 150 parts by mass of ethyl acetate as a solvent to the compound (A) solution and mixing them.

  Subsequently, the prepared pressure-sensitive adhesive layer composition was applied to a base film so that the dry film thickness was 20 μm, and dried at 110 ° C. for 3 minutes to prepare a pressure-sensitive adhesive film. In addition, 4 types of adhesive films 13A-13D from which a base film differs were produced as an adhesive film.

  The adhesive film 13A is an adhesive film that uses an ethylene-vinyl acetate copolymer base film having a thickness of 100 μm as the base film. The adhesive film 13B is an adhesive film using a high-density polyethylene film having a thickness of 110 μm as a base film. The adhesive film 13C is an adhesive film using a high-density polyethylene film having a thickness of 100 μm as a base film. The pressure-sensitive adhesive film 13D is a pressure-sensitive adhesive film using a base film composed of two layers of a high-density polyethylene layer having a thickness of 100 μm, a random copolymer polypropylene, and a styrene / butadiene copolymer layer. .

(Formation of wafer processing tape according to Examples 1 to 8)
The release film with a thickness of 38 μm on which the above-mentioned adhesive layer having a thickness of 5 μm, which has been refrigerated, is returned to room temperature, and the first cut portion is formed so as to reach the release film from the surface of the adhesive layer. Then, circular precut processing with a diameter of 220 mm was performed (primary precut processing). Then, the unnecessary part of the adhesive bond layer was removed, and the adhesive film was laminated at room temperature. Next, the second cut portion is formed so as to reach the release film on the adhesive film outside the bonded adhesive layer, and the diameter is concentric with the adhesive layer (shape matched to the wafer ring frame shape). A 290 mm circular precut process was attempted (secondary precut process). Thus, production of the wafer processing tapes according to Examples 1 to 8 was tried.

  In addition, when trying the secondary pre-cut process, in the laminated portion where the release film and the adhesive film are laminated, the laminated portion corresponding to the position where the first cut portion is located (FIG. 1 (c)) using an optical sensor. The transmittance A of 600 to 700 nm wavelength of the laminated portion 27b) and the transmittance B of 600 to 700 nm wavelength of the laminated portion (laminated portion 27a in FIG. 1C) corresponding to the position where there is no first cut portion. Based on the rate difference C, the first cut portion was recognized, and based on the recognized first cut portion, a circular precut process with a diameter of 290 mm was attempted concentrically with the adhesive layer. The optical sensor is not particularly limited as long as it can detect light in the wavelength range of 290 to 850 nm.

(Formation of wafer processing tape according to Comparative Examples 1 to 3)
The wafer processing tapes according to Comparative Examples 1 to 3 were manufactured in the same manner as the wafer processing tapes according to Examples 1 to 8 described above. Moreover, the recognition method at the time of trying secondary precut processing is the same as the recognition method at the time of trying secondary precut processing in the tapes for wafer processing according to Examples 1 to 8 described above.

  Sensor recognizability was evaluated about the produced tapes for wafer processing concerning Examples 1-8 and Comparative Examples 1-3. The results of sensor recognizability evaluation for the wafer processing tapes according to Examples 1 to 8 are shown in Table 1, and the results of sensor recognizability evaluation for the wafer processing tapes according to Comparative Examples 1 to 3 are shown in Table 2. Indicated.

The tape for wafer processing which concerns on Examples 1-5 uses the above-mentioned adhesive film 13A as an adhesive film, and the depth of the 1st notch part formed in the release film in the case of a primary precut process is used for a precut blade. This is a wafer processing tape whose transmittance is adjusted by changing the indentation pressure (clearance).
In the tapes for wafer processing according to Examples 6 and 7, the transmittance was adjusted by using the above-mentioned adhesive film 13C as an adhesive film in Example 6, and using the above-mentioned adhesive film 13D as an adhesive film in Example 7. This is a wafer processing tape.
The tape for wafer processing according to Example 8 uses the above-mentioned adhesive film 13B as an adhesive film, and further presses the depth of the first cut portion formed in the release film at the time of the primary precut processing into the precut blade. This is a wafer processing tape whose transmittance is adjusted by changing the pressure (clearance) and processing it shallowly.

The tape for wafer processing according to Comparative Example 1 uses the above-mentioned adhesive film 13D as an adhesive film, and further presses the depth of the first cut portion formed in the release film at the time of the primary precut processing into the precut blade. This is a wafer processing tape whose transmittance is adjusted by changing the pressure (clearance) and processing it shallowly.
The tape for wafer processing according to Comparative Example 2 uses the above-mentioned adhesive film 13A as an adhesive film, and determines the depth of the first cut portion formed in the release film during the primary precut processing by the pressing pressure of the precut blade. This is a wafer processing tape whose transmittance is adjusted by changing (clearance).
The tape for wafer processing according to Comparative Example 3 uses the above-mentioned adhesive film 13B as an adhesive film, and further presses the depth of the first cut portion formed in the release film at the time of the primary precut processing into the precut blade. This is a wafer processing tape whose transmittance is adjusted by processing deeper by changing the pressure (clearance).

<Measurement of transmittance>
Using a spectrophotometer UV3101PC manufactured by Shimadzu Corporation, in a laminated part in which a release film and an adhesive film are laminated, the transmittance A (%) of the laminated part with the first cut part and the lamination without the first cut part 2 The transmittance B (%) of the part was measured for the wafer processing tapes according to Examples 1 to 8 and Comparative Examples 1 to 3. In addition, the measured transmittance | permeability is a transmittance | permeability of 600-700 nm wavelength.

<Measurement of the ratio D (%) of the depth of the first cut portion to the total thickness of the release film>
Cut out the first cut part attached to the release film by the primary pre-cut to an appropriate size, fill it with an epoxy resin, etc., and polish the specimen embedded in the solidified resin. Then, the depth of the first cut portion was measured and observed using an optical microscope or the like. Thereafter, the ratio D was calculated from the measured depth of the first cut portion and the total thickness of the release film.

<Evaluation of sensor recognition>
When producing the wafer processing tapes of Examples 1 to 8 and Comparative Examples 1 to 3, the optical sensor is used to perform the recognition operation as described above (in the case of the wafer processing tapes of Examples 1 to 8, the first In the case of the wafer processing tapes of Comparative Examples 1 to 3 by recognizing the cut portion, the operation of recognizing the laminated portion in which the release film, the adhesive layer, and the adhesive film are laminated) The wafer processing tapes of Comparative Examples 1 to 3 were each performed 50 times, the ratio of the number of times the secondary precut blade was rotated and the second cut portion was formed at a predetermined position was examined, and sensor recognition was evaluated. It was. Here, in Table 1, the number of times of recognition indicates the number of times that the secondary pre-cut blade has rotated and the second cut portion can be formed at a predetermined position, and the success rate is the ratio of the number of times of recognition during 50 recognition operations. (%).

  As shown in Table 1, the wafer processing tapes of Examples 1 to 8 were able to form the second cut portion in the secondary pre-cut processing 45 to 50 times in 50 recognition operations. That is, the success rate was 90 to 100%. In particular, the wafer processing tapes of Examples 2 to 4 had a success rate of 100%.

  On the other hand, as shown in Table 2, with the wafer processing tape of Comparative Example 1, it was possible to form the second cut in the secondary pre-cut processing step only 5 times out of 50 recognition operations. That is, the success rate was 10%. In the wafer processing tape of Comparative Example 2, the release film was broken during the production of the wafer processing tape, and the wafer processing tape could not be manufactured. Therefore, the transmittance A, the transmittance difference C, and the sensor recognizability cannot be measured. In the wafer processing tape of Comparative Example 3, the second cut in the secondary precut processing step could be formed only 5 times during the 50 recognition operations. That is, the success rate was 10%.

  From the above results, even in the case where the thickness of the adhesive layer is 5 μm, in the laminated portion where the release film and the adhesive film are laminated, the laminated portion corresponding to the position of the first cut portion (FIG. 1 ( The transmittance A of 600 to 700 nm wavelength of the laminated portion 27b) of c) and the transmittance B of 600 to 700 nm wavelength of the laminated portion (the laminated portion 27a of FIG. 1C) corresponding to the position where there is no first cut portion. It was found that the wafer processing tape 10 according to Examples 1 to 8 formed so that the transmittance difference C was 0.1% or more had good label recognizability and precut workability. In particular, it was found that the wafer processing tape 10 according to Examples 2 to 4 formed so that the transmittance difference C was 0.6 to 1.3% had good label recognizability and precut processability. .

DESCRIPTION OF SYMBOLS 10, 10a, 10b: Wafer processing tape 11: Release film 12: Adhesive layer 13: Adhesive film 20: Dicing die bonding film 22: Label shape adhesion part 23a: Label part 23b: Peripheral part 25: 1st laminated body 26: 1st cut part 27: 2nd laminated body 28: 2nd cut part 29: 3rd cut part

Claims (7)

A long release film,
One or more adhesive layers having a predetermined planar shape provided on the release film;
One or more pressure-sensitive adhesive films each covering the adhesive layer and provided so as to contact the release film around the adhesive layer;
A wafer processing tape comprising:
In the release film, an annular cut portion along the outer periphery of the adhesive layer is formed on the surface of the release film on which the adhesive layer is laminated,
In the laminated part where the release film and the adhesive film are laminated, it corresponds to the transmittance A (%) of the laminated part corresponding to the position with the cut part and the position without the cut part. A wafer processing tape, wherein a transmittance difference C (= A−B) between the laminated portion and the transmittance B (%) at a wavelength of 600 to 700 nm is 0.1 or more . 2. The wafer processing tape according to claim 1, wherein the transmittance difference C is 0.6 to 1.3 .   The wafer processing tape according to claim 1, wherein the transmittance A is 75 to 95%.   4. The wafer processing according to claim 1, further comprising a peripheral portion made of the adhesive film provided on the release film so as to surround the outside of the adhesive film. 5. Tape. (A) A plurality of adhesive layers having a predetermined planar shape are provided on a long release film, and the adhesive film is laminated on the adhesive film in which the release film and the adhesive layer are laminated in this order. A step of laminating an adhesive film so as to cover the agent layer and to contact the release film around the adhesive layer;
(B) In the laminate composed of the adhesive film and the pressure-sensitive adhesive film formed by the step (a), the laminate portion composed of the release film and the pressure-sensitive adhesive film is moved from the surface of the pressure-sensitive adhesive film. Forming a plurality of annular second notches surrounding each of the adhesive layers until reaching the release film;
A method for producing a wafer processing tape comprising:
Before the step (a),
(C) When providing the plurality of adhesive layers having a predetermined planar shape on the release film, an annular first cut portion along the outer periphery of the adhesive layer is provided on the release film. Comprising the step of forming
In the step (b), in the laminated portion where the release film and the adhesive film are laminated, a transmittance A (%) of a wavelength of 600 to 700 nm of the laminated portion corresponding to a position where the cut portion is present Based on the transmittance difference C (= A−B) between the release film and the transmittance B (%) at a wavelength of 600 to 700 nm of the laminated portion corresponding to the position where the cut portion is not present, the first cut. Recognizing a portion, and forming an annular second cut portion surrounding the adhesive layer based on the recognized first cut portion ,
In the step (c), the first cut portion is formed so that the transmittance difference C is 0.1 or more . The said process (c) forms the said 1st notch part so that the said transmittance | permeability difference C may be 0.6-1.3 , The manufacture of the tape for wafer processing of Claim 5 characterized by the above-mentioned. Method. Instead of the step (b), (d) in the laminate composed of the adhesive film and the adhesive film formed by the step (a), the release film and the adhesive film, A plurality of annular second notches surrounding each adhesive layer from the surface of the adhesive film to the release film are formed in the laminated portion, and the outside of the second notches The method for producing a wafer processing tape according to claim 5, further comprising a step of forming a third cut portion .

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