JP2018203974A - Tape for semiconductor processing - Google Patents

Abstract

A semiconductor processing tape including an adhesive layer having sufficient adhesion to a wafer even after being thermally cured by heat treatment in a manufacturing process of a semiconductor device. A semiconductor processing tape according to the present invention comprises a base material layer, an adhesive layer provided on the surface of the base material layer, and a thermosetting adhesive layer provided on the surface of the adhesive layer. The release film provided on the surface of the adhesive layer is provided in this order, and the adhesive layer has a storage elastic modulus at 80 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour. [Selection] Figure 1

Description

  The present invention relates to a semiconductor processing tape.

In recent years, there is an increasing demand for downsizing, weight reduction, and high functionality of electronic devices. In response to these demands, semiconductor devices constituting electronic devices are required to be downsized, thinned, and mounted with high density.
A semiconductor device is manufactured through a sealing process for sealing a semiconductor chip fixed to a substrate, glass, or a temporary fixing material with a resin, a dicing process for separating the sealed semiconductor chip as needed, and the like. . In the manufacturing process, a wafer polishing step may be performed.
These steps are often carried out with the chip or substrate covered with a protective tape. The protective tape is usually attached to a surface to be protected before a specific processing step, and is peeled off after the processing step.

  Patent Document 1 discloses a heat-resistant adhesive sheet for semiconductor manufacturing used for manufacturing a substrate-less semiconductor package that does not use a metal lead frame, an adhesive used for the sheet, and a method for manufacturing a semiconductor device using the sheet. To do.

JP 2011-129649 A

  By the way, in recent years, various kinds of packages and their manufacturing processes have been developed, and the performance required for adhesive tapes for temporarily fixing adherends such as chips, semiconductor wafers, and substrates is also changing. For example, a process for temporarily fixing a wafer to a substrate through an adhesive layer after the adhesive layer of the adhesive tape is exposed to a high temperature environment resulting from heat treatment in the manufacturing process of the semiconductor device has been proposed. However, according to the study by the present inventors, the adhesive force of the conventional adhesive tape decreases due to the influence of heat, so that, for example, the wafer is peeled off from the substrate during transport of the wafer temporarily fixed to the substrate. This causes a problem in the next process.

  The present invention has been made in view of the above problems, and provides a semiconductor processing tape provided with an adhesive layer having sufficient adhesion to a wafer even after heat curing by heat treatment in the manufacturing process of a semiconductor device. The purpose is to provide.

  A tape for semiconductor processing according to the present invention comprises: a base material layer; an adhesive layer provided on the surface of the base material layer; a thermosetting adhesive layer provided on the surface of the adhesive layer; A release film provided on the surface is provided in this order, and the adhesive layer has a storage elastic modulus at 80 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour.

  That the storage elastic modulus at 80 ° C. of the adhesive layer is 7 MPa or less means that the adhesive layer has sufficient flexibility even after the adhesive layer receives a heat history of about 1 hour at 170 ° C. means. Since the adhesive layer is flexible, excellent adhesion to the adherend can be realized. Specifically, the adhesive layer preferably has a peel peel strength of 8 N / m or more after being cured at 170 ° C. for 1 hour. As used herein, “peel peel strength” means peel peel force measured at a peel speed of 50 mm / min and a peel angle of 90 °.

  As an application of the semiconductor processing tape according to the present invention, there is a temporary fixing of a wafer to a substrate. That is, the semiconductor processing tape according to the present invention temporarily fixes the substrate to the first surface of the adhesive layer after peeling the release film and peels the base material layer and the adhesive layer in the manufacturing process of the semiconductor device. It can be used to temporarily fix the wafer to the second surface of the adhesive layer. As described above, when the semiconductor processing tape is used for temporarily fixing, none of the base material layer, the adhesive layer, the adhesive layer, and the release film remain in the finally manufactured semiconductor device.

  The adhesive layer preferably has a storage elastic modulus at 120 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour. When the adhesive layer satisfies this requirement, the adhesion to the wafer is more stably exhibited.

  The adhesive layer preferably includes at least a thermoplastic resin and a thermosetting resin. In this case, when the content of the thermoplastic resin in the adhesive layer is 100 parts by mass, the content of the thermosetting resin in the adhesive layer is preferably 1 part by mass or more and less than 30 parts by mass. When the adhesive layer satisfies this requirement, the adhesion to the wafer is more stably exhibited.

  According to the present invention, there is provided a semiconductor processing tape provided with an adhesive layer having sufficient adhesion to a wafer even after being thermally cured by heat treatment in the process of manufacturing a semiconductor device.

FIG. 1 is a cross-sectional view schematically showing one embodiment of a semiconductor processing tape of the present invention. 2A to 2F are cross-sectional views schematically showing a process of manufacturing a semiconductor device using the semiconductor processing tape shown in FIG. 1 as a temporary fixing tape. 3A to 3D are cross-sectional views schematically showing a process for manufacturing a semiconductor device, following the process shown in FIG. FIG. 4 is a cross-sectional view schematically showing an example of a semiconductor device.

  Embodiments of the present invention will be described below with reference to the drawings as appropriate. In addition, this invention is not limited to the following embodiment. In this specification, (meth) acryl means acryl or methacryl.

<Tape for semiconductor processing>
FIG. 1 is a cross-sectional view schematically showing a semiconductor processing tape according to this embodiment. In the semiconductor processing tape 10 shown in the figure, a base material layer 1, an adhesive layer 2, a thermosetting adhesive layer 3, and a release film 4 are laminated in this order. The adhesive layer 3 of the semiconductor processing tape 10 has a storage elastic modulus at 80 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour. The adhesive layer 3 has excellent adhesion to the adherend after receiving the heat history as described above. The semiconductor processing tape 10 provided with such an adhesive layer 3 can be applied to various processes in the manufacturing process of a semiconductor device, and can be suitably applied particularly to temporary fixing of members.
The width of the semiconductor processing tape 10 is, for example, 200 to 400 mm, and may be 10 to 200 mm or 400 to 600 mm.

  As described above, the adhesive layer 3 has a storage elastic modulus at 80 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour, preferably 5 MPa or less, more preferably 3 MPa or less. preferable. When this value is 7 MPa or less, excellent adhesion to the adherend can be realized. From the viewpoint of more stably achieving excellent adhesion, the adhesive layer 3 preferably has a storage elastic modulus at 120 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour, and 5 MPa or less. It is more preferable that it is 3 MPa or less. In addition, both the lower limits of the storage elastic modulus in 80 degreeC and 120 degreeC of the contact bonding layer 3 after the said heat history are 1 Mpa, for example.

  The storage elastic modulus of the adhesive layer 3 can be obtained as follows. The semiconductor processing tape 10 is cut into a predetermined size, and then the base material layer 1 and the adhesive layer 2 are peeled off to prepare a sample made of a laminate of the adhesive layer 3 and the release film 4. This is heated at 170 ° C. for 1 hour to be cured. A sample is obtained by cutting the adhesive layer 3 thus obtained after the curing treatment into a predetermined size (for example, 4 mm × 30 mm). The elastic modulus of this sample is measured using a dynamic viscoelasticity measuring device (). That is, a tensile load is applied to the sample, and measurement is performed from −50 ° C. to 300 ° C. under conditions of a frequency of 10 Hz and a temperature rising rate of 10 ° C./min.

  After the curing treatment at 170 ° C. for 1 hour, the peel strength of the adhesive layer 3 to the wafer is preferably 8 N / m or more, more preferably 10 to 30 N / m, and more preferably 20 to 30 N. More preferably, it is / m. When the peel peel force is 8 N / m or more, sufficient adhesion to the wafer can be ensured.

  After the curing treatment at 170 ° C. for 1 hour, the shrinkage rate of the adhesive layer 3 is preferably less than 2%, more preferably 1.8% or less, and further preferably 1.6% or less. When this value is less than 2%, even when heat is applied to the adhesive layer 3 while the wafer or the substrate is temporarily fixed to the adhesive layer 3 in the manufacturing process of the semiconductor device, the displacement can be sufficiently suppressed. .

The shrinkage rate of the adhesive layer 3 can be determined as follows. The semiconductor processing tape 10 is cut into a predetermined size (for example, 100 mm × 100 mm), and a base material layer 1 and an adhesive layer 2 are peeled off from this to prepare a sample composed of a laminate of the adhesive layer 3 and the release film 4. . This is heated at 130 ° C. for 1 hour to be cured, and the size of the adhesive layer 3 after the curing treatment is measured. The shrinkage rate is calculated by substituting the sample area before thermosetting and the sample area after thermosetting into the following equation.
Shrinkage (%) = (Sample area after curing) / (Sample area before curing) × 100

  The adhesive layer 3 preferably includes a thermoplastic resin, a thermosetting resin, a curing accelerator, and a filler. The preferable range of the content of these components when the content of the thermoplastic resin in the adhesive layer 3 is 100 parts by mass is as follows. That is, the content of the thermosetting resin in the adhesive layer 3 is preferably 1 part by mass or more and less than 30 parts by mass, more preferably 5 to 29 parts by mass, and further preferably 10 to 28 parts by mass. preferable. The content of the curing accelerator in the adhesive layer 3 is preferably 0.01 to 3 parts by mass, more preferably 0.02 to 2 parts by mass, and 0.03 to 1 part by mass. Further preferred. The filler content in the adhesive layer 3 is preferably 1 to 330 parts by mass, more preferably 1 to 300 parts by mass, further preferably 5 to 200 parts by mass, and 10 to 100 parts by mass. It is particularly preferred. The adhesive layer 3 satisfying these requirements can further improve the adhesion, heat resistance and peelability required in various processing steps in the manufacturing process of the semiconductor device.

  It is preferable that the adhesive layer 3 and the pressure-sensitive adhesive layer 2 are sufficiently in contact with each other so that peeling does not occur during the processing step. The adhesive force between the adhesive layer 3 and the adhesive layer 2 can be evaluated by the T-peel strength of both. 15 N / m or more is preferable and, as for the T-shaped peeling strength (peeling speed: 50 mm / min) of the contact bonding layer 3 and the adhesion layer 2, 16-100 N / m is more preferable. The T-shaped peel strength is determined by the following method. After bonding the adhesive layer 3 and the adhesive layer 2 with a laminator, a measurement sample is prepared by making a 25 mm wide cut. At this time, when a UV irradiation type adhesive is used, light UV irradiation is appropriately performed. The peeling speed is measured at 50 mm / min.

  Hereinafter, the adhesive layer 3, the pressure-sensitive adhesive layer 2, the base material layer 1, and the release film 4 that constitute the semiconductor processing tape 10 will be described.

[Adhesive layer]
As described above, the adhesive layer 3 preferably includes a thermoplastic resin, a thermosetting resin, a curing accelerator, and a filler.

(Thermoplastic resin)
As the thermoplastic resin, a resin having thermoplasticity, or a resin having thermoplasticity at least in an uncured state and forming a crosslinked structure after heating can be used. As a thermoplastic resin, a (meth) acrylic copolymer having a reactive group (hereinafter referred to as “reactive group-containing (meth) acrylic copolymer) as a semiconductor processing tape from the viewpoint of excellent shrinkage, heat resistance and peelability. In some cases, it is also referred to as “polymer”.
When the reactive group-containing (meth) acrylic copolymer is included as the thermoplastic resin, the adhesive layer 3 may not include the thermosetting resin. That is, the aspect containing a reactive group containing (meth) acrylic copolymer, a hardening accelerator, and a filler may be sufficient.
A thermoplastic resin can be used individually by 1 type or in combination of 2 or more types.

  Examples of the (meth) acrylic copolymer include (meth) acrylic acid ester copolymers such as acrylic glass and acrylic rubber, and acrylic rubber is preferable. The acrylic rubber is preferably formed by copolymerization of a monomer mainly composed of an acrylic ester and selected from (meth) acrylic ester and acrylonitrile.

(Meth) acrylic acid esters include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, Examples include isopropyl acrylate, butyl methacrylate, isobutyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, and lauryl methacrylate.
The (meth) acrylic acid ester copolymer is preferably a copolymer containing butyl acrylate and acrylonitrile as a copolymer component, and a copolymer containing ethyl acrylate and acrylonitrile as a copolymer component.

  The reactive group-containing (meth) acrylic copolymer is preferably a reactive group-containing (meth) acrylic copolymer containing a (meth) acrylic monomer having a reactive group as a copolymerization component. Such a reactive group-containing (meth) acrylic copolymer can be obtained by copolymerizing a monomer composition containing a (meth) acrylic monomer having a reactive group and the above monomer. .

  As the reactive group, an epoxy group, a carboxyl group, an acryloyl group, a methacryloyl group, a hydroxyl group, and an episulfide group are preferable from the viewpoint of improving heat resistance, and an epoxy group and a carboxyl group are more preferable from the viewpoint of crosslinkability.

  In the present embodiment, the reactive group-containing (meth) acrylic copolymer is preferably an epoxy group-containing (meth) acrylic copolymer containing a (meth) acrylic monomer having an epoxy group as a copolymerization component. In this case, as the (meth) acrylic monomer having an epoxy group, glycidyl acrylate, 4-hydroxybutyl acrylate glycidyl ether, 3,4-epoxycyclohexylmethyl acrylate, glycidyl methacrylate, 4-hydroxybutyl methacrylate glycidyl ether, 3,4- Examples include epoxy cyclohexyl methyl methacrylate. The (meth) acrylic monomer having a reactive group is preferably glycidyl acrylate or glycidyl methacrylate from the viewpoint of heat resistance.

  The Tg of the thermoplastic resin is preferably -50 ° C to 50 ° C. It is easy to ensure the softness | flexibility of the contact bonding layer 3 as Tg of a thermoplastic resin is 50 degrees C or less. In addition, when unevenness is present when pasting on the adherend, it becomes easy to follow and has appropriate adhesiveness. On the other hand, when the Tg of the thermoplastic resin is −50 ° C. or higher, it is easy to suppress the flexibility of the adhesive layer 3 from becoming too high, and excellent handleability, adhesiveness, and peelability can be achieved.

  Tg of a thermoplastic resin is a midpoint glass transition temperature value obtained by differential scanning calorimetry (DSC). Specifically, the Tg of the thermoplastic resin is an intermediate value calculated by a method according to JIS K 7121: 1987 by measuring a change in calorie under conditions of a temperature rising rate of 10 ° C./min and a measurement temperature of −80 to 80 ° C. It is the point glass transition temperature.

  The weight average molecular weight of the thermoplastic resin is preferably 100,000 or more and 2,000,000 or less. When the weight average molecular weight is 100,000 or more, it is easy to ensure heat resistance when used for temporary fixation. On the other hand, when the weight average molecular weight is 2 million or less, it is easy to suppress a decrease in flow and a decrease in pastability when used for temporary fixation. From the viewpoint described above, the weight average molecular weight of the thermoplastic resin is more preferably 500,000 to 2,000,000, and further preferably 1,000,000 to 2,000,000. In addition, a weight average molecular weight is a polystyrene conversion value using the calibration curve by a standard polystyrene by the gel permeation chromatography method (GPC).

  When the (meth) acrylic copolymer having a reactive group contains glycidyl acrylate or glycidyl methacrylate as a copolymer component, these contents are in total, 0.1 to 20% by mass based on the total amount of the copolymer component Preferably, it is 0.5 to 15% by mass, and more preferably 1.0 to 10% by mass. When the content is within the above range, the flexibility, adhesiveness, and peelability of the adhesive layer 3 can be achieved at a higher level.

  As the (meth) acrylic copolymer having a reactive group as described above, one obtained by a polymerization method such as pearl polymerization or solution polymerization may be used. Alternatively, commercially available products such as HTR-860P-3CSP (trade name, manufactured by Nagase ChemteX Corporation) may be used.

(Thermosetting resin)
As the thermosetting resin, any resin that can be cured by heat can be used without particular limitation. Examples of the thermosetting resin include an epoxy resin, an acrylic resin, a silicone resin, a phenol resin, a thermosetting polyimide resin, a polyurethane resin, a melamine resin, and a urea resin. These can be used individually by 1 type or in combination of 2 or more types.

  The epoxy resin is not particularly limited as long as it is cured and has a heat resistance. As the epoxy resin, a bifunctional epoxy resin such as a bisphenol A type epoxy, a novolac type epoxy resin such as a phenol novolac type epoxy resin, a cresol novolak type epoxy resin, or the like can be used. As the epoxy resin, conventionally known ones such as a polyfunctional epoxy resin, a glycidylamine type epoxy resin, a heterocyclic ring-containing epoxy resin, and an alicyclic epoxy resin can be used.

As the bisphenol A type epoxy resin, Epicoat 807, Epicoat 815, Epicoat 825, Epicoat 827, Epicoat 828, Epicoat 834, Epicoat 1001, Epicoat 1004, Epicoat 1007, Epicoat 1009 (all manufactured by Mitsubishi Chemical Corporation), DER- 330, DER-301, DER-361 (all manufactured by Dow Chemical Company), YD8125, YDF8170 (all manufactured by Tohto Kasei Co., Ltd.) and the like.
Examples of the phenol novolac type epoxy resin include Epicoat 152, Epicoat 154 (all manufactured by Mitsubishi Chemical Corporation), EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), DEN-438 (manufactured by Dow Chemical Company), and the like. .
As the o-cresol novolac type epoxy resin, YDCN-700-10 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1012, EOCN-1025, EOCN-1027 (any Are also available from Nippon Kayaku Co., Ltd.), YDCN701, YDCN702, YDCN703, YDCN704 (all manufactured by Tohto Kasei Co., Ltd.).
As the polyfunctional epoxy resin, Epon 1031S (manufactured by Mitsubishi Chemical Corporation), Araldite 0163 (manufactured by BASF Japan), Denacol EX-611, EX-614, EX-614B, EX-622, EX-512, EX- 521, EX-421, EX-411, EX-321 (all manufactured by Nagase ChemteX Corporation).
As an amine type epoxy resin, Epicoat 604 (manufactured by Mitsubishi Chemical Corporation), YH-434 (manufactured by Toto Kasei Co., Ltd.), TETRAD-X, TETRAD-C (all manufactured by Mitsubishi Gas Chemical Co., Ltd.), ELM -120 (manufactured by Sumitomo Chemical Co., Ltd.).
Examples of the heterocyclic ring-containing epoxy resin include Araldite PT810 (manufactured by BASF Japan), ERL4234, ERL4299, ERL4221, and ERL4206 (all manufactured by Union Carbide). These epoxy resins can be used individually by 1 type or in combination of 2 or more types.

As the epoxy resin curing agent that is a part of the thermosetting resin component, a commonly used known resin can be used. Specifically, bisphenols having at least two phenolic hydroxyl groups in one molecule such as amines, polyamides, acid anhydrides, polysulfides, boron trifluoride, bisphenol A, bisphenol F, and bisphenol S, phenol novolac resins And phenol resins such as bisphenol A novolac resin and cresol novolac resin. As the epoxy resin curing agent, phenol resins such as phenol novolak resin, bisphenol A novolak resin, and cresol novolak resin are particularly preferable from the viewpoint of excellent electric corrosion resistance during moisture absorption.
In addition, an epoxy hardening | curing agent may be used simultaneously with an epoxy resin, and may be used independently.

  Among the phenol resin curing agents, Phenolite LF2882, Phenolite LF2822, Phenolite TD-2090, Phenolite TD-2149, Phenolite VH-4150, Phenolite VH4170 (both manufactured by DIC Corporation, trade name), H-1 (Maywa Kasei Co., Ltd., trade name), EpiCure MP402FPY, EpiCure YL6065, EpiCure YLH129B65, Mirex XL, Mirex XLC, Mirex XLC-LL, Mirex RN, Mirex RS, Mirex VR (all Mitsubishi Chemical Corporation ), Product name).

(Curing accelerator)
Curing accelerators include imidazoles, dicyandiamide derivatives, dicarboxylic acid dihydrazide, triphenylphosphine, tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole-tetraphenylborate, 1,8-diazabicyclo [5,4, 0] undecene-7-tetraphenylborate and the like. These can be used individually by 1 type or in combination of 2 or more types.

  When the contact bonding layer 3 contains the (meth) acrylic copolymer which has an epoxy group, it is preferable to contain the hardening accelerator which accelerates | stimulates hardening of the epoxy group contained in the said acrylic copolymer. Curing accelerators that accelerate the curing of epoxy groups include phenolic curing agents, acid anhydride curing agents, amine curing agents, imidazole curing agents, imidazoline curing agents, triazine curing agents, and phosphine curing agents. Can be mentioned. Among these, from the viewpoint of fast curability, heat resistance, and peelability, an imidazole-based curing agent that can be expected to shorten process time and improve workability is preferable. These compounds can be used individually by 1 type or in combination of 2 or more types.

  The content of the curing accelerator in the adhesive layer 3 is preferably 0.02 to 20 parts by mass, more preferably 0.025 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic resin. More preferably, it is 0.025-3 mass parts, and it is especially preferable that it is 0.025-0.05. When the content of the curing accelerator is within the above range, the storage stability tends to be sufficiently suppressed while improving the curability of the adhesive layer 3.

(Inorganic filler)
In the adhesive layer 3, an inorganic filler can be blended. Examples of the inorganic filler include metal fillers such as silver powder, gold powder, and copper powder, and nonmetallic inorganic fillers such as silica, alumina, boron nitride, titania, glass, iron oxide, and ceramic. The inorganic filler can be selected according to the desired function.

  The inorganic filler preferably has an organic group on the surface. Since the surface of the inorganic filler is modified with an organic group, the dispersibility in an organic solvent when preparing the varnish for forming the adhesive layer 3 and the shrinkage of the adhesive layer 3 can be suppressed, and the elastic modulus can be reduced. It becomes easy to improve and improve peelability.

  The inorganic filler having an organic group on the surface can be obtained, for example, by mixing a silane coupling agent represented by the following formula (B-1) and an inorganic filler and stirring at a temperature of 30 ° C. or higher. It can be confirmed by UV measurement, IR measurement, XPS measurement or the like that the surface of the inorganic filler is modified with an organic group.

In formula (B-1), X represents an organic group selected from the group consisting of a phenyl group, a glycidoxy group, an acryloyl group, a methacryloyl group, a mercapto group, an amino group, a vinyl group, an isocyanate group, and a methacryloxy group, and s Represents an integer of 0 or 1 to 10, and R ¹¹ , R ¹² and R ¹³ each independently represents an alkyl group having 1 to 10 carbon atoms.
Examples of the alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, isopropyl group and isobutyl group. .
The alkyl group having 1 to 10 carbon atoms is preferably a methyl group, an ethyl group or a pentyl group from the viewpoint of easy availability. From the viewpoint of heat resistance, X is preferably an amino group, a glycidoxy group, a mercapto group, or an isocyanate group, and more preferably a glycidoxy group or a mercapto group. S in formula (B-1) is preferably 0 to 5, and more preferably 0 to 4 from the viewpoint of suppressing film fluidity during high heat and improving heat resistance.

Examples of the silane coupling agent include trimethoxyphenylsilane, dimethyldimethoxyphenylsilane, triethoxyphenylsilane, dimethoxymethylphenylsilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2 -Aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycid Xylpropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-meta Liloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N, N′-bis (3- (trimethoxysilyl) propyl) ethylenediamine, polyoxyethylenepropyltrialkoxysilane, polyethoxydimethylsiloxane and the like can be mentioned.
Among these, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, and 3-mercaptopropyltrimethoxysilane are preferable, and trimethoxyphenylsilane, 3-glycidoxy Propyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane are more preferable. A silane coupling agent can be used individually by 1 type or in combination of 2 or more types.

  The content of the coupling agent is preferably 0.01 to 50 parts by mass with respect to 100 parts by mass of the inorganic filler, from the viewpoint of achieving a balance between heat resistance and storage stability. More preferably, it is 0.5 parts by mass from the viewpoint of improving heat resistance.

  The content of the inorganic filler in the adhesive layer 3 is preferably 330 parts by mass or less, more preferably 180 parts by mass or less, and further preferably 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. preferable. Although there is no restriction | limiting in particular in content of an inorganic filler, It is preferable that it is 1 mass part or more with respect to 100 mass parts of thermoplastic resins, It is more preferable that it is 5 mass parts or more, It is 8 mass parts or more. More preferably. By making content of an inorganic filler into the said range, the shrinkage | contraction property of the contact bonding layer 3 is suppressed, it becomes easy to improve an elasticity modulus and to improve peelability.

(Organic filler)
An organic filler can be blended in the adhesive layer 3. Examples of the organic filler include carbon, rubber filler, silicone fine particles, polyamide fine particles, and polyimide fine particles. The content of the organic filler is preferably 300 parts by mass or less, more preferably 200 parts by mass or less, and still more preferably 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. Although the minimum of content of an organic filler does not have a restriction | limiting in particular, It is preferable that it is 5 mass parts or more with respect to 100 mass parts of thermoplastic resins.

(Organic solvent)
The adhesive layer 3 may be further diluted with an organic solvent as necessary. The organic solvent is not particularly limited, but can be determined in consideration of the volatility during film formation from the boiling point. Specifically, a relatively low boiling point solvent such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, xylene, It is preferable from the viewpoint that curing is difficult to proceed. For the purpose of improving the film forming property, it is preferable to use a solvent having a relatively high boiling point such as dimethylacetamide, dimethylformamide, N-methylpyrrolidone, cyclohexanone. These solvents can be used singly or in combination of two or more.

[Adhesive layer]
As the pressure-sensitive adhesive layer 2, those having a pressure-sensitive adhesive force at room temperature and having an adhesive force to the adhesive layer 3 are preferable. As the pressure-sensitive adhesive layer 2, both a pressure-sensitive type and a photo-curing type (which is cured by high energy rays such as ultraviolet rays or radiation) can be used, but the pressure-sensitive type has a surface of an adherend that is lighter than the photo-curing type. It is preferable to adopt a pressure-sensitive type in that it is easy to suppress roughening. The pressure-sensitive adhesive layer 2 may be a photo-curing type or a non-photo-curing type (for example, one that is cured by heat).

When using a photocurable pressure-sensitive adhesive, the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 2 preferably contains an acrylic copolymer (acrylic resin), a crosslinking agent, and a photopolymerization initiator.
When using a non-photo-curing adhesive, the epoxy resin, isocyanate group, aziridine group, and melanin group are selected as the crosslinking agent that reacts with the base resin and the functional group of the base resin through a crosslinking reaction to adjust the adhesive strength. It is preferable to have at least one kind of functional group. These cross-linking agents may be used alone or in combination of two or more.
Examples of the base resin include acrylic resin, various synthetic rubbers, natural rubber, and polyimide resin. From the viewpoint of preventing the adhesive from being left behind, the base resin preferably has a functional group capable of reacting with other additives such as a hydroxyl group and a carboxyl group.
Moreover, when reaction rate is slow, catalysts, such as an amine or tin, can be used suitably. In order to adjust the adhesive properties, optional components such as rosin-based and terpene resin-based tackifiers, various surfactants and the like may be appropriately contained so as not to affect the effects of the present invention.

  The thickness of the pressure-sensitive adhesive layer 2 is preferably 1 to 100 μm, more preferably 2 to 50 μm, and further preferably 5 to 40 μm. If the thickness of the pressure-sensitive adhesive layer 2 is less than 1 μm, it may be difficult to secure a sufficient adhesive force with the adhesive layer, which may make it difficult to process. There is no advantage.

[Base material layer]
As the base material layer 1, a known polymer sheet or tape can be used. Specific examples include crystalline polypropylene, amorphous polypropylene, high density polyethylene, medium density polyethylene, low density polyethylene, very low density polyethylene, low density linear polyethylene, polybutene, polymethyl pentene, and other polyolefins, ethylene-vinyl acetate. Polymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, polyurethane, Polyester such as polyethylene terephthalate and polyethylene naphthalate, polycarbonate, polyimide, polyetheretherketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide, polyphenylsulfide, aramid (paper), gallium Scan, glass cloth, fluorine resin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, and silicone resin. A mixture in which a plasticizer, silica, an antiblocking material, a slip agent, an antistatic agent and the like are mixed can also be used.

  Among the above, at least one selected from polypropylene, polyethylene-polypropylene random copolymer, polyethylene-polypropylene block copolymer, ethylene-vinyl acetate copolymer, ionomer resin, and ethylene- (meth) acrylic acid copolymer. The layer as the main component is preferably in contact with the adhesive layer. These resins are preferable from the viewpoints of characteristics such as Young's modulus, stress relaxation, melting point, etc., cost, and recycling of used materials after use, and also from the viewpoint of easily obtaining the surface modification effect by ultraviolet rays.

  The base material layer 1 may be a single layer, but may have a multilayer structure in which layers made of different materials are laminated as necessary. As a method for producing such a base material, a base material layer having different layers may be formed at a time by a multilayer extrusion method, or a tape made by an inflation method or a single layer extrusion method is bonded using an adhesive. Or may be obtained by a technique such as bonding by heat welding. Moreover, in order to control the adhesiveness with the adhesion layer 2 to the base material layer 1, you may perform surface roughening processes, such as a mat | matte process and a corona treatment, as needed.

[Peeling film]
The release film 4 is formed of polyethylene terephthalate (PET), polyethylene, polypropylene, or the like. The release film 4 may contain an arbitrary filler. In addition, the surface of the release film 4 may be subjected to release treatment or plasma treatment.

<Method for producing semiconductor processing tape>
The semiconductor processing tape 10 can be produced, for example, by the method described below. That is, first, a material obtained by dissolving the raw resin composition of the adhesive layer 3 in a solvent such as an organic solvent on the release film 4 to form a varnish, a knife coating method, a roll coating method, a spray coating method, a gravure coating method, Coating is performed by a bar coating method, a curtain coating method, or the like, and the solvent is removed to form the adhesive layer 3. Then, the laminated body which consists of the base material layer 1 and the adhesion layer 2 produced separately is laminated | stacked at normal temperature-60 degreeC. Thereby, the tape 10 for semiconductor processing by which the adhesion layer 2, the contact bonding layer 3, and the peeling film 4 were laminated | stacked in this order on the base material layer 1 can be obtained.

<Use of semiconductor processing tape as temporary fixing tape>
The semiconductor processing tape 10 peels the base layer 1 and the adhesive layer 2 while temporarily fixing the substrate to the first surface F1 of the adhesive layer 3 after peeling the release film 4 in the manufacturing process of the semiconductor device. Thereafter, it can be used to temporarily fix the wafer to the second surface F2 of the adhesive layer 3. The substrate is not particularly limited as long as it can support the adhesive layer 3 and has heat resistance capable of withstanding the above temperature, and examples thereof include a silicon substrate, a glass substrate, and a quartz substrate. Examples of the wafer include a semiconductor wafer.

  2A to 2F are cross-sectional views showing a process for manufacturing a semiconductor device using the semiconductor processing tape 10 as a temporary fixing tape. When the semiconductor processing tape 10 is used as a temporary fixing tape, none of the base material layer 1, the adhesive layer 2, the adhesive layer 3 and the release film 4 remain in the finally manufactured semiconductor device (FIG. 3 ( d) and FIG. 4).

  First, the release film 4 of the semiconductor processing tape 10 is peeled off. The semiconductor processing tape 10A (after the release film 4 is peeled off) is applied to the substrate S so that the exposed first surface F1 of the adhesive layer 3 and the surface of the substrate S are in contact with each other (FIG. 2A). ). The temperature at this time may be about 50 to 90 ° C. By bonding them together under this temperature condition, the adhesive force between the adhesive layer 3 and the substrate S can be made larger than the adhesive force between the adhesive layer 3 and the adhesive layer 2. That is, the board | substrate S is for controlling the adhesiveness of the contact bonding layer 3 in the state in which the contact bonding layer 3 was bonded together. In addition, the adhesive layer 3 in a state of being bonded to the substrate S is a layer having predetermined heat resistance as well as being controlled by applying heat.

  By peeling the base material layer 1 and the pressure-sensitive adhesive layer 2 from the state shown in FIG. 2A, a laminate 20 composed of the substrate S and the adhesive layer 3 is obtained as shown in FIG. 2B. By applying heat to the laminate 20, specifically, for example, by applying a curing process to the adhesive layer 3 at 170 ° C. for about 1 hour, the adhesive force of the adhesive layer 3 is further controlled. be able to. After such curing treatment, the adhesive layer 3 has excellent adhesion to the wafer W because the storage elastic modulus at 80 ° C. of the adhesive layer 3 is 7 MPa or less.

  Subsequently, the semiconductor wafer W is bonded to the adhesive layer 3 so that the surface Ws of the semiconductor wafer W is in contact with the second surface F2 of the adhesive layer 3 after the curing treatment as described above. The surface opposite to the surface Ws of the semiconductor wafer W is the circuit surface Wc. Thereby, as shown in FIG. 2C, the stacked body 30 in which the substrate S is bonded to the first surface F <b> 1 of the adhesive layer 3 and the semiconductor wafer W is bonded to the second surface F <b> 2 of the adhesive layer 3. can get. What is necessary is just to make the temperature at the time of bonding the contact bonding layer 3 and the semiconductor wafer W into about 50-90 degreeC. By bonding the adhesive layer 3 and the semiconductor wafer W under this temperature condition, the adhesive force between the adhesive layer 3 and the semiconductor wafer W is larger than the adhesive force between the adhesive layer 3 and the substrate S. can do.

  After performing necessary processing (for example, microbump bonding) on the semiconductor wafer W in the stacked body 30 shown in FIG. 2C, the substrate S is peeled off. Thereby, the laminated body 40 which consists of the wafer W and the contact bonding layer 3 which are shown by FIG.2 (d) is obtained. 2E, the semiconductor wafer W is mounted on the support substrate 50 having the dicing film 50a on the surface with the circuit surface Wc of the semiconductor wafer W facing the support substrate 50. As shown in FIG. The dicing film 50a may be appropriately selected from conventional ones. Next, as shown in FIG. 2F, the adhesive layer 3, the semiconductor wafer W, and the dicing film 50a are diced. At this time, the support substrate 50 may be diced halfway. At this time, the adhesive layer 3 serves to protect the semiconductor wafer W.

  Next, as shown in FIG. 3A, by expanding the support substrate 50, the semiconductor elements Wa obtained by cutting are separated from each other, and the adhesion pushed up by the needle 42 from the support substrate 51 side. The layered semiconductor element 60 is sucked and picked up by the suction collet 44. The semiconductor element 60 with an adhesive layer includes a semiconductor element Wa and an adhesive layer 3a. The semiconductor element Wa is obtained by dividing the semiconductor wafer W, and the adhesive layer 3a is obtained by dividing the adhesive layer 3. In the pick-up process, it is not always necessary to perform expansion, but the pick-up property can be further improved by expanding. Further, the push-up amount by the needle 42 can be selected as necessary. Furthermore, from the viewpoint of ensuring sufficient pickup performance even for an ultra-thin wafer, for example, a two-stage or three-stage pickup method may be performed. Further, the semiconductor element 60 may be picked up by a method other than the suction collet 44.

  As shown in FIG. 3B, a plurality of bumps Wb are formed on the circuit surface Wc of the semiconductor element Wa. Thereafter, as shown in FIG. 3C, the semiconductor element 60 with an adhesive layer is bonded to the support substrate 70 for mounting the semiconductor element by thermocompression bonding. Then, the structure 80 shown in FIG. 3D is obtained by peeling off the adhesive layer 3a that has protected the upper surface of the semiconductor element Wa.

  Subsequently, as shown in FIG. 4, it is preferable to electrically connect the semiconductor element Wa and the support substrate 70 by wire bonds 90 as necessary. Furthermore, after connecting by wire bonding, the semiconductor element Wa may be resin-sealed as necessary. A resin sealing material 95 is formed on the surface 70a of the support substrate 70, and a solder ball 75 is formed on the surface opposite to the surface 70a of the support substrate 70 for electrical connection with an external substrate (motherboard). May be.

  The present invention will be described based on examples. The present invention is not limited to the following examples.

(Preparation of adhesive film)
An acrylic copolymer was obtained by a solution polymerization method using the following main monomer and functional group monomer as an adhesive. That is, 2-ethylhexyl acrylate and methyl methacrylate were used as main monomers, and hydroxyethyl acrylate and acrylic acid were used as functional group monomers. The acrylic copolymer had a weight average molecular weight of 400,000 and a glass transition point of -38 ° C. A pressure-sensitive adhesive solution was prepared by blending 10 parts by mass of a polyfunctional isocyanate crosslinking agent (trade name: Mytec NY730A-T, manufactured by Mitsubishi Chemical Corporation) with respect to 100 parts by mass of this acrylic copolymer. A pressure-sensitive adhesive solution was applied and dried on a surface release-treated polyethylene terephthalate (thickness: 25 μm) so that the thickness of the pressure-sensitive adhesive during drying was 10 μm. Further, a polyolefin substrate (thickness: 100 μm) made of polypropylene / vinyl acetate / polypropylene was laminated on the pressure-sensitive adhesive surface. Thereby, the adhesive film which consists of an adhesion layer and a polyolefin base material (base material layer) was obtained. The pressure-sensitive adhesive film was allowed to stand at room temperature for 2 weeks and sufficiently aged.

<Example 1>
(Preparation of adhesive varnish)
The following materials were mixed and vacuum degassed to obtain an adhesive varnish.
Thermoplastic resin: HTR-860P-3 (trade name, manufactured by Nagase ChemteX Corp., glycidyl group-containing acrylic rubber, molecular weight: 1,000,000, Tg: -7 ° C.) 100 parts by mass Thermosetting component: Millex XLC- LL (trade name, manufactured by Mitsui Chemicals, Phenol aralkyl resin, hydroxyl group equivalent 174) 17 parts by mass, thermosetting component: YDCN-700-10 (trade name, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., o-cresol novolak type) Epoxy resin, epoxy equivalent 210) 20 parts by mass / curing accelerator: 2PZ-CN (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd., imidazole compound) 0.04 parts by mass / inorganic filler: Aerosil R972 (trade name, Nippon Aerosil) Co., Ltd., silicon oxide, spherical silica, average particle size of about 0.16 μm) 12 parts by mass, additive (silane coupling agent): appropriate amount Agent (cyclohexanone): appropriate amount

(Preparation of tape for semiconductor processing)
The adhesive varnish was applied on a 75 μm-thick surface release-treated polyethylene terephthalate (Teijin DuPont Films, Teijin Tetron Film: A-31). As a result, an adhesive sheet having an adhesive layer formed on one surface of the resin film was obtained. The adhesive sheet and the adhesive film were bonded together to obtain a semiconductor processing tape. In addition, the adhesive sheet and the adhesive film were bonded together so that the adhesive layer of the adhesive sheet and the adhesive layer of the adhesive film were in direct contact. Since the adhesive layer sticks to the adhesive layer, the adhesive layer formed on the polyethylene terephthalate can be reliably reversed to the adhesive layer side.

(Example 2)
A tape for semiconductor processing was obtained in the same manner as in Example 1 except that each material used for preparing the adhesive varnish was formulated as shown in Example 2 of Table 1.

(Comparative Example 1)
A tape for semiconductor processing was obtained in the same manner as in Example 1 except that each material used for the preparation of the adhesive varnish was formulated as shown in Comparative Example 1 of Table 1. “EXA-830CRP” in Table 1 is a trade name of a thermosetting resin (bisphenol F type epoxy resin, epoxy equivalent 170) manufactured by DIC Corporation.

(Comparative Example 2)
A tape for semiconductor processing was obtained in the same manner as in Example 1 except that each material used for preparing the adhesive varnish was blended as shown in Comparative Example 2 of Table 1. In Table 1, “LF-4871” is a trade name of a thermosetting resin (bisphenol A type epoxy resin, epoxy equivalent 118) manufactured by DIC Corporation, and “YDF-8170C” is Nippon Steel & Sumikin Chemical Co., Ltd. This is a product name of a thermosetting resin (bisphenol F type epoxy resin, epoxy equivalent 157), and “SC-2050-HLG” is a product name of a filler manufactured by Admatechs Co., Ltd.

(Comparative Example 3)
A tape for semiconductor processing was obtained in the same manner as in Example 1, except that each material used for preparing the adhesive varnish was blended as shown in Comparative Example 3 of Table 1.

The tape for semiconductor processing which concerns on an Example and a comparative example was evaluated with the following method.
(1) Storage elastic modulus of adhesive layer after curing treatment Semiconductor processing tapes according to Examples and Comparative Examples were each cut into a size of 100 mm × 100 mm. The adhesive film (adhesive layer and substrate layer) and the surface release-treated polyethylene terephthalate were peeled off from each sample to form only the adhesive layer, which was used as a measurement sample. The measurement samples according to Examples and Comparative Examples were cured by heating at 170 ° C. for 1 hour. Using the dynamic viscoelasticity measuring device DVE-V4 (trade name, manufactured by Rheology Co., Ltd.), the tensile modulus was applied to the elastic modulus of the sample after the curing treatment, and the conditions were a frequency of 10 Hz and a heating rate of 10 ° C./min. Measured from -50 ° C to 300 ° C. From the results, the storage elastic modulus at temperatures of 80 ° C. and 120 ° C. was obtained. In Table 1, a sample having a storage modulus value of 7 MPa or less was designated as “A”, and a sample that was greater than 7 MPa was designated as “B”.

(2) 90 ° peel peeling force of adhesive layer to wafer (Evaluation of adhesion strength to wafer)
A sample obtained by cutting the cured sample used for evaluation of the storage elastic modulus into a width of 10 mm was used as a measurement sample. A measurement sample was attached to the surface of a silicon wafer. Thereafter, an adhesive tape (auxiliary tape) was applied to the measurement sample, and the measurement sample was peeled off from the wafer at an angle of 90 ° at 50 mm / min. In Table 1, a sample having a 90 ° peel peel value of 8 N / m or more was designated as “A”, and a sample that was less than 8 N / m was designated as “B”.

DESCRIPTION OF SYMBOLS 1 ... Base material layer, 2 ... Adhesive layer, 3 ... Adhesive layer, 4 ... Release film, 10 ... Semiconductor processing tape, S ... Substrate, W ... Semiconductor wafer.

Claims (5)

A base material layer;
An adhesive layer provided on the surface of the base material layer;
A thermosetting adhesive layer provided on the surface of the adhesive layer;
A release film provided on the surface of the adhesive layer;
A semiconductor processing tape comprising:
The adhesive layer is a semiconductor processing tape having a storage elastic modulus at 80 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour.   2. The semiconductor processing tape according to claim 1, wherein the adhesive layer has a storage elastic modulus at 120 ° C. of 7 MPa or less after being cured at 170 ° C. for 1 hour.   3. The semiconductor processing tape according to claim 1, wherein the adhesive layer has a peel peeling force of 8 N / m or more on the wafer after being cured at 170 ° C. for 1 hour.   The semiconductor processing according to any one of claims 1 to 3, wherein none of the base material layer, the adhesive layer, the adhesive layer, and the release film is left in a finally manufactured semiconductor device. Tape. The adhesive layer includes at least a thermoplastic resin and a thermosetting resin,
The content of the thermosetting resin in the adhesive layer when the content of the thermoplastic resin in the adhesive layer is 100 parts by mass is 1 part by mass or more and less than 30 parts by mass. The tape for semiconductor processing as described in any one.

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