JP7035347B2 - Semiconductor processing tape - Google Patents

Description

The present invention relates to a tape for semiconductor processing.

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

Patent Document 1 discloses a heat-resistant adhesive sheet for semiconductor manufacturing used for manufacturing a substrateless 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. do.

Japanese Unexamined Patent Publication No. 2011-129649

By the way, in recent years, while a wide variety of packages and their manufacturing processes have been developed, the performance required for adhesive tapes for temporarily fixing adherends such as chips, semiconductor wafers and substrates is also changing. For example, a process has been proposed in which an adhesive layer of an adhesive tape is exposed to a high temperature environment caused by heat treatment in a process of manufacturing a semiconductor device, and then a wafer is temporarily fixed to a substrate via the adhesive layer. However, according to the studies by the present inventors, in the conventional adhesive tape, the adhesive force of the adhesive layer is reduced due to the influence of heat, and as a result, for example, the wafer is peeled off from the substrate when the wafer temporarily fixed to the substrate is conveyed. This is the cause of problems in the next process.

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

The 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, and an adhesive layer. A release film provided on the surface is provided in this order, and the adhesive layer has a storage elastic modulus of 7 MPa or less at 80 ° C. after being cured at 170 ° C. for 1 hour.

The fact that the storage elastic modulus of the adhesive layer at 80 ° C. is 7 MPa or less means that the adhesive layer has sufficient flexibility even after the adhesive layer has undergone a thermal history at 170 ° C. for about 1 hour. means. Since the adhesive layer is flexible, excellent adhesion to the adherend can be realized. Specifically, it is preferable that the adhesive layer has a peel peeling force of 8 N / m or more with respect to the wafer after being cured at 170 ° C. for 1 hour. The "peel peeling force" as used herein means a peel peeling force measured at a peeling speed of 50 mm / min and a peeling angle of 90 °.

An application of the semiconductor processing tape according to the present invention includes temporary fixing of a wafer to a substrate. That is, in the semiconductor processing tape according to the present invention, in the manufacturing process of the semiconductor device, after the release film is peeled off, the substrate is temporarily fixed to the first surface of the adhesive layer, and after the base material layer and the adhesive layer are peeled off. 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 temporary fixing, none of the base material layer, the adhesive layer, the adhesive layer and the release film remains in the finally manufactured semiconductor device.

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

The adhesive layer preferably contains 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 adhesive force to the wafer is more stably exhibited.

INDUSTRIAL APPLICABILITY 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 heat-cured by heat treatment in the manufacturing process of a semiconductor device.

FIG. 1 is a cross-sectional view schematically showing an embodiment of the semiconductor processing tape of the present invention. 2 (a) to 2 (f) 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. 3 (a) to 3 (d) are cross-sectional views schematically showing a step of manufacturing a semiconductor device, which is a step following the step shown in FIG. 2 (f). FIG. 4 is a cross-sectional view schematically showing an example of a semiconductor device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. The present invention is not limited to the following embodiments. As used herein, the term (meth) acrylic means acrylic or methacrylic.

<Semiconductor processing tape>
FIG. 1 is a cross-sectional view schematically showing a semiconductor processing tape according to the present 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 of 7 MPa or less at 80 ° C. 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 the adhesive layer 3 can be applied to various steps in the manufacturing process of the semiconductor device, and is particularly preferably applicable to temporary fixing of members to each other.
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 of 7 MPa or less, preferably 5 MPa or less, and more preferably 3 MPa or less after being cured at 170 ° C. for 1 hour. preferable. When this value is 7 MPa or less, excellent adhesion to the adherend can be realized. From the viewpoint of achieving excellent adhesion more stably, the adhesive layer 3 preferably has a storage elastic modulus of 7 MPa or less at 120 ° C. after being cured at 170 ° C. for 1 hour, preferably 5 MPa or less. It is more preferably 3 MPa or less, and further preferably 3 MPa or less. The lower limit of the storage elastic modulus of the adhesive layer 3 after the thermal history at 80 ° C. and 120 ° C. is, for example, 1 MPa.

The storage elastic modulus of the adhesive layer 3 can be obtained as follows. The semiconductor processing tape 10 is cut to a predetermined size, and the base material layer 1 and the adhesive layer 2 are peeled off to prepare a sample composed of a laminate of the adhesive layer 3 and the release film 4. This is heated at 170 ° C. for 1 hour to cure. A sample is obtained by cutting the adhesive layer 3 after the curing treatment thus obtained 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 the measurement is performed from −50 ° C. to 300 ° C. under the conditions of a frequency of 10 Hz and a heating rate of 10 ° C./min.

After being cured at 170 ° C. for 1 hour, the peel peeling force of the adhesive layer 3 with respect to the wafer is preferably 8 N / m or more, more preferably 10 to 30 N / m, and more preferably 20 to 30 N. It is more preferably / m. When the peel peeling 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, still more preferably 1.6% or less. When this value is less than 2%, misalignment can be sufficiently suppressed even if heat is applied to the adhesive layer 3 in a state where the wafer or the substrate is temporarily fixed to the adhesive layer 3 in the manufacturing process of the semiconductor device. ..

The shrinkage rate of the adhesive layer 3 can be obtained as follows. The semiconductor processing tape 10 is cut into a predetermined size (for example, 100 mm × 100 mm), and the base material layer 1 and the adhesive layer 2 are peeled off from the sample to prepare a sample consisting 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 rate (%) = (sample area after curing) / (sample area before curing) x 100

The adhesive layer 3 preferably contains a thermoplastic resin, a thermosetting resin, a curing accelerator, and a filler. When the content of the thermoplastic resin in the adhesive layer 3 is 100 parts by mass, the preferable range of the content of these components 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 preferably 0.03 to 1 part by mass. More preferred. The content of the filler 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 preferable to have. The adhesive layer 3 satisfying these requirements can further stably 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 adhesive layer 2 are sufficiently adhered so as not to cause peeling during the processing process. The adhesive strength between the adhesive layer 3 and the adhesive layer 2 can be evaluated by the T-shaped peel strength of both. The T-shaped peel strength (peeling speed: 50 mm / min) of the adhesive layer 3 and the adhesive layer 2 is preferably 15 N / m or more, more preferably 16 to 100 N / m. The T-shaped peel strength is determined by the following method. A sample for measurement is prepared by bonding the adhesive layer 3 and the adhesive layer 2 with a laminator and then making a notch with a width of 25 mm. 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 adhesive layer 2, the base material layer 1, and the release film 4 constituting the semiconductor processing tape 10 will be described.

[Adhesive layer]
As described above, the adhesive layer 3 preferably contains 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 at least thermoplasticity in an uncured state and forming a crosslinked structure after heating can be used. As the thermoplastic resin, as a tape for semiconductor processing, a (meth) acrylic copolymer having a reactive group from the viewpoint of excellent shrinkage, heat resistance and peelability (hereinafter, “reactive group-containing (meth) acrylic” It may also be referred to as "polymer").
When the thermoplastic resin contains a reactive group-containing (meth) acrylic copolymer, the adhesive layer 3 may not contain a thermosetting resin. That is, an embodiment containing a reactive group-containing (meth) acrylic copolymer, a curing accelerator, and a filler may be used.
The thermoplastic resin may be used alone or in combination of two or more.

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 copolymerizing an acrylic acid ester as a main component and a monomer selected from (meth) acrylic acid ester and acrylonitrile.

Examples of the (meth) acrylic acid ester 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, and propyl methacrylate. Examples thereof include isopropyl acrylate, butyl methacrylate, isobutyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate and lauryl methacrylate.
As the (meth) acrylic acid ester copolymer, a copolymer containing butyl acrylate and acrylonitrile as a copolymerization component and a copolymer containing ethyl acrylate and acrylonitrile as a copolymerization component are preferable.

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 (meth) acrylic monomer having a reactive group and a monomer composition containing the above-mentioned 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, examples of the (meth) acrylic monomer having an epoxy group include glycidyl acrylate, 4-hydroxybutyl acrylate glycidyl ether, 3,4-epoxycyclohexylmethyl acrylate, glycidyl methacrylate, 4-hydroxybutyl methacrylate glycidyl ether, and 3,4-. Epoxycyclohexylmethylmethacrylate and the like can be mentioned. As the (meth) acrylic monomer having a reactive group, glycidyl acrylate and glycidyl methacrylate are preferable from the viewpoint of heat resistance.

The Tg of the thermoplastic resin is preferably −50 ° C. to 50 ° C. When the Tg of the thermoplastic resin is 50 ° C. or lower, it is easy to secure the flexibility of the adhesive layer 3. Further, if there are irregularities when the material is attached to the adherend, it becomes easy to follow the surface and has an appropriate adhesiveness. On the other hand, when the Tg of the thermoplastic resin is −50 ° C. or higher, it is easy to prevent the adhesive layer 3 from becoming too flexible, and excellent handleability, adhesiveness, and peelability can be achieved.

The Tg of the thermoplastic resin is an intermediate point glass transition temperature value obtained by differential scanning calorimetry (DSC). Specifically, the Tg of the thermoplastic resin is an intermediate calculated by a method based on JIS K 7121: 1987 by measuring the change in calorific value under the conditions of a heating rate of 10 ° C./min and a measurement temperature of -80 to 80 ° C. The point glass transition temperature.

The weight average molecular weight of the thermoplastic resin is preferably 100,000 or more and 2 million or less. When the weight average molecular weight is 100,000 or more, it becomes easy to secure heat resistance when used for temporary fixing. 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 stickability when used for temporary fixing. From the above viewpoint, the weight average molecular weight of the thermoplastic resin is more preferably 500,000 or more and 2 million or less, and further preferably 1 million or more and 2 million or less. The weight average molecular weight is a polystyrene-equivalent value using a calibration curve made of standard polystyrene by gel permeation chromatography (GPC).

When the (meth) acrylic copolymer having a reactive group contains glycidyl acrylate or glycidyl methacrylate as a copolymerization component, the total content thereof is 0.1 to 20% by mass based on the total amount of the copolymerization component. It is preferably present, more preferably 0.5 to 15% by mass, still 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, a commercially available product 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 epoxy resin, acrylic resin, silicone resin, phenol resin, thermosetting polyimide resin, polyurethane resin, melamine resin, and urea resin. These can be used alone or in combination of two or more.

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

Examples of the bisphenol A type epoxy resin include 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 Corporation), YD8125, YDF8170 (all manufactured by Toto Kasei Co., Ltd.) and the like can be mentioned.
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 Corporation), DEN-438 (manufactured by Dow Chemical Corporation), and the like. ..
Examples of the o-cresol novolak type epoxy resin include YDCN-700-10 (manufactured by Nippon Steel & Sumitomo Metal Corporation), EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1012, EOCN-1025, and EOCN-1027 (any of them). (Made by Nippon Kayaku Co., Ltd.), YDCN701, YDCN702, YDCN703, YDCN704 (all manufactured by Toto Kasei Co., Ltd.) and the like.
Examples of the polyfunctional epoxy resin include Epon 1031S (manufactured by Mitsubishi Chemical Corporation), Araldite 0163 (manufactured by BASF Japan), Denacol EX-611, EX-614, EX-614B, EX-622, EX-512, and EX-. 521, EX-421, EX-411, EX-321 (all manufactured by Nagase ChemteX Corporation) and the like can be mentioned.
As the 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 Corporation) and the like can be mentioned.
Examples of the heterocyclic-containing epoxy resin include Araldite PT810 (manufactured by BASF Japan Ltd.), ERL4234, ERL4299, ERL4221 and ERL4206 (all manufactured by Union Carbide). These epoxy resins can be used alone or in combination of two or more.

As the epoxy resin curing agent which is a part of the thermosetting resin component, a commonly used known resin can be used. Specifically, bisphenols and phenol novolak resins having two or more phenolic hydroxyl groups in one molecule, such as amines, polyamides, acid anhydrides, polysulfides, boron trifluoride, bisphenol A, bisphenol F, and bisphenol S. , Bisphenol A novolak resin, phenolic resin such as cresol novolak resin and the like. As the epoxy resin curing agent, phenolic resins such as phenol novolac resin, bisphenol A novolak resin, and cresol novolak resin are particularly preferable from the viewpoint of excellent electrolytic corrosion resistance during moisture absorption.
The epoxy curing agent may be used at the same time as the epoxy resin, or may be used alone.

Among the above phenol resin curing agents, Phenolite LF2882, Phenolite LF2822, Phenolite TD-2090, Phenolite TD-2149, Phenolite VH-4150, Phenolite VH4170 (all manufactured by DIC Co., Ltd., trade name), H-1 (manufactured by Meiwa Kasei Co., Ltd., trade name), Epicure MP402FPY, Epicure YL6065, Epicure YLH129B65, Millex XL, Millex XLC, Millex XLC-LL, Millex RN, Millex RS, Millex VR (all from Mitsubishi Chemical Co., Ltd.) ), It is preferable to use the trade name).

(Curing accelerator)
Examples of the curing accelerator 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 can be mentioned. These can be used alone or in combination of two or more.

When the adhesive layer 3 contains a (meth) acrylic copolymer having an epoxy group, it is preferable to contain a curing accelerator that promotes curing of the epoxy group contained in the acrylic copolymer. Examples of the curing accelerator that promotes the curing of the epoxy group include a phenol-based curing agent, an acid anhydride-based curing agent, an amine-based curing agent, an imidazole-based curing agent, an imidazoline-based curing agent, a triazine-based curing agent, and a phosphine-based curing agent. Can be mentioned. Among these, an imidazole-based curing agent, which can be expected to shorten the process time and improve workability, is preferable from the viewpoint of quick curing property, heat resistance and peelability. These compounds may be used alone or in combination of two or more.

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, and 0, with respect to 100 parts by mass of the thermoplastic resin. It is more preferably 2.025 to 3 parts by mass, and particularly preferably 0.025 to 0.05. When the content of the curing accelerator is within the above range, there is a tendency that the deterioration of the storage stability can be sufficiently suppressed while improving the curing property of the adhesive layer 3.

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

The inorganic filler preferably has an organic group on its surface. Since the surface of the inorganic filler is modified with an organic group, the dispersibility in an organic solvent when preparing a varnish for forming the adhesive layer 3 and the shrinkage of the adhesive layer 3 can be suppressed, and the elastic modulus can be improved. It becomes easy to improve and improve the 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 the inorganic filler and stirring at a temperature of 30 ° C. or higher. It is possible to confirm that the surface of the inorganic filler is modified by the organic group by UV measurement, IR measurement, XPS measurement and the like.

In the 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 Indicates 0 or an integer of 1 to 10, and R ¹¹ , R ¹² and R ¹³ each independently indicate an alkyl group having 1 to 10 carbon atoms.
Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an isopropyl group and an isobutyl group. ..
The alkyl group having 1 to 10 carbon atoms is preferably a methyl group, an ethyl group and 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 and an isocyanate group, and more preferably a glycidoxy group and a mercapto group. The s in the formula (B-1) is preferably 0 to 5, and more preferably 0 to 4 from the viewpoint of suppressing the film fluidity at the time of high heat and improving the heat resistance.

Examples of the silane coupling agent include trimethoxyphenylsilane, dimethyldimethoxyphenylsilane, triethoxyphenylsilane, dimethoxymethylphenylsilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, and N- (2). -Aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycid Xipropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-isoxapropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- Mercaptopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propaneamine, N, N'-bis (3- (tri) Examples thereof include methoxysilyl) propyl) ethylenediamine, polyoxyethylenepropyltrialkoxysilane, and polyethoxydimethylsiloxane.
Among these, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isoxapropyltriethoxysilane, and 3-mercaptopropyltrimethoxysilane are preferable, and trimethoxyphenylsilane and 3-glycidoxy are preferable. Propyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane are more preferred. The silane coupling agent may be used alone or in combination of two or more.

The content of the coupling agent is preferably 0.01 to 50 parts by mass and 0.05 to 20 parts by mass with respect to 100 parts by mass of the inorganic filler from the viewpoint of balancing heat resistance and storage stability. It is more preferably parts by mass, and further preferably 0.5 to 10 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. The lower limit of the content of the inorganic filler is not particularly limited, but is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and 8 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin. Is even more preferable. By setting the content of the inorganic filler in the above range, the shrinkage of the adhesive layer 3 can be suppressed, the elastic modulus can be improved, and the peelability can be easily improved.

(Organic filler)
An organic filler can be blended in the adhesive layer 3. Examples of the organic filler include carbon, rubber-based filler, silicone-based fine particles, polyamide fine particles, polyimide fine particles, and the like. The content of the organic filler is preferably 300 parts by mass or less, more preferably 200 parts by mass or less, and even more preferably 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. The lower limit of the content of the organic filler is not particularly limited, but is preferably 5 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin.

(Organic solvent)
The adhesive layer 3 may be further diluted with an organic solvent, if necessary. The organic solvent is not particularly limited, but can be determined in consideration of the volatility at the time of film formation and the like from the boiling point. Specifically, a solvent having a relatively low boiling point such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, and xylene is used to form a film during film formation. It is preferable from the viewpoint that curing does not proceed easily. Further, 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 and cyclohexanone. These solvents may be used alone or in combination of two or more.

[Adhesive layer]
As the adhesive layer 2, it is preferable that the adhesive layer 2 has an adhesive force at room temperature and has an adhesive force with respect to the adhesive layer 3. As the adhesive layer 2, both a pressure-sensitive type and a photocurable type (those that are cured by high energy rays such as ultraviolet rays or radiation) can be adopted, but the pressure-sensitive type has a surface of the adherend more than the photocurable type. It is preferable to use a pressure-sensitive type because it is easy to suppress roughening. Further, the adhesive layer 2 may be a photocurable type or a non-photocurable type (for example, one that is cured by heat).

When a photocurable pressure-sensitive adhesive is used, it is preferable that the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 2 contains an acrylic copolymer (acrylic resin), a cross-linking agent, and a photopolymerization initiator.
When a non-photocurable pressure-sensitive adhesive is used, it is selected from an epoxy group, an isocyanate group, an aziridine group and a melanin group as a cross-linking agent that reacts with the base resin and the functional group of the base resin by a cross-linking reaction in order 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 rubbers, polyimide resins and the like. From the viewpoint that the adhesive does not easily remain on the adhesive, the base resin preferably has a functional group capable of reacting with other additives, such as a hydroxyl group and a carboxyl group.
If the reaction rate is slow, a catalyst such as amine or tin can be used as appropriate. In order to adjust the adhesive properties, arbitrary components such as rosin-based and terpene resin-based tack fires and various surfactants may be appropriately contained to the extent that the effects of the present invention are not affected.

The thickness of the adhesive layer 2 is preferably 1 to 100 μm, more preferably 2 to 50 μm, and even more preferably 5 to 40 μm. If the thickness of the adhesive layer 2 is thinner than 1 μm, it becomes difficult to secure sufficient adhesive force with the adhesive layer and it may be difficult to process. On the other hand, if the thickness is thicker than 100 μm, it is uneconomical and characteristic. There is no advantage.

[Base layer]
As the base material layer 1, a known polymer sheet or tape can be used. Specific examples include polymers such as crystalline polypropylene, amorphous polypropylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, ultra-low-density polyethylene, low-density linear polyethylene, polybutene, and polymethylpentene, as well as ethylene-vinyl acetate. Polymers, ionomer resins, polyethylene- (meth) acrylic acid copolymers, ethylene- (meth) acrylic acid ester (random, alternating) copolymers, polyethylene-butene copolymers, polyethylene-hexene copolymers, polyurethanes, Polyethylene terephthalate, polyethylene naphthalate and other polyesters, polycarbonate, polyimide, polyether ether ketone, polyimide, polyetherimide, polyamide, all aromatic polyamide, polyphenylsulfide, aramid (paper), glass, glass cloth, fluororesin, poly Examples thereof include vinyl chloride, polyvinylidene chloride, cellulose-based resins, and silicone resins. A mixture of a plasticizer, silica, an anti-blocking material, a slip agent, an antistatic agent and the like 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 is selected. It is preferable that the layer as the main component is in contact with the adhesive layer. These resins are preferable from the viewpoints of properties such as Young's modulus, stress relaxation property, melting point, price, waste material recycling after use, and the like, and are also preferable from the viewpoint that the surface modification effect by ultraviolet rays can be easily obtained.

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, if necessary. As a method for producing such a base material, a base material layer having different layers may be made at one time by a multi-layer extrusion method, or tapes made by an inflation method or a single-layer extrusion method are bonded together using an adhesive. Or it may be obtained by a method such as bonding by heat welding. Further, in order to control the adhesion of the base material layer 1 to the adhesive layer 2, a surface roughening treatment such as a matte treatment or a corona treatment may be performed, if necessary.

[Release film]
The release film 4 is made of polyethylene terephthalate (PET), polyethylene, polypropylene or the like. The release film 4 may contain any filler. Further, the surface of the release film 4 may be subjected to a mold release treatment, a plasma treatment, or the like.

<Method of manufacturing semiconductor processing tape>
The semiconductor processing tape 10 can be manufactured, for example, by the method described below. That is, first, a varnished product obtained by dissolving the raw material resin composition of the adhesive layer 3 in a solvent such as an organic solvent on the release film 4 is subjected to a knife coating method, a roll coating method, a spray coating method, a gravure coating method, and the like. The adhesive layer 3 is formed by removing the solvent by coating by a bar coating method, a curtain coating method or the like. Then, a separately prepared laminate composed of the base material layer 1 and the adhesive layer 2 is laminated at room temperature to 60 ° C. As a result, the semiconductor processing tape 10 in which the adhesive layer 2, the adhesive layer 3 and the release film 4 are laminated in this order can be obtained on the base material layer 1.

<Use of semiconductor processing tape as temporary fixing tape>
In the semiconductor processing tape 10, after the release film 4 was peeled off in the manufacturing process of the semiconductor device, the substrate was temporarily fixed to the first surface F1 of the adhesive layer 3, and the base material layer 1 and the adhesive layer 2 were peeled off. Later, 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 that can withstand 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 and the like.

2 (a) to 2 (f) are cross-sectional views showing a process of 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 remains in the finally manufactured semiconductor device (FIG. 3 (FIG. 3). d) and FIG. 4).

First, the release film 4 of the semiconductor processing tape 10 is peeled off. A semiconductor processing tape 10A (after peeling the release film 4) is attached to the substrate S so that the first surface F1 of the adhesive layer 3 exposed thereby 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 the two together under these temperature conditions, 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 substrate S is for controlling the adhesiveness of the adhesive layer 3 in a state where the adhesive layer 3 is bonded. The adhesive layer 3 in a state of being bonded to the substrate S is a layer having a predetermined heat resistance as well as being controlled in adhesiveness by applying heat.

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

Subsequently, the semiconductor wafer W is attached 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 of the semiconductor wafer W opposite to the surface Ws is the circuit surface Wc. As a result, as shown in FIG. 2C, the laminate 30 in which the substrate S is bonded to the first surface F1 of the adhesive layer 3 and the semiconductor wafer W is bonded to the second surface F2 of the adhesive layer 3 is formed. can get. The temperature at which the adhesive layer 3 and the semiconductor wafer W are bonded to each other may be about 50 to 90 ° C. By adhering the adhesive layer 3 and the semiconductor wafer W under these temperature conditions, the adhesive force between the adhesive layer 3 and the semiconductor wafer W becomes 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 laminate 30 shown in FIG. 2C, the substrate S is peeled off. As a result, the laminated body 40 composed of the wafer W and the adhesive layer 3 shown in FIG. 2D is obtained. Subsequently, as shown in FIG. 2E, the semiconductor wafer W is mounted on the support substrate 50 having the dicing film 50a on the surface in a state where the circuit surface Wc of the semiconductor wafer W faces the support substrate 50. The dicing film 50a may be appropriately selected from conventional ones. Next, as shown in FIG. 2 (f), 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 plays a role of protecting 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 is pushed up from the support substrate 51 side by the needle 42. The layered semiconductor element 60 is sucked and picked up by the suction collet 44. The semiconductor element 60 with an adhesive layer has 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 expand, but by expanding, the pick-up property can be further improved. Further, the push-up amount by the needle 42 can be selected as needed. Further, from the viewpoint of ensuring sufficient pick-up performance even for ultra-thin wafers, 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. Then, 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, by peeling off the adhesive layer 3a that protected the upper surface of the semiconductor element Wa, the structure 80 shown in FIG. 3D can be obtained.

Subsequently, as shown in FIG. 4, it is preferable to electrically connect the semiconductor element Wa and the support substrate 70 by a wire bond 90, if necessary. Further, after connecting by wire bonding, the semiconductor element Wa may be resin-sealed as needed. The resin encapsulant 95 is formed on the surface 70a of the support substrate 70, while the solder balls 75 are formed on the surface of the support substrate 70 opposite to the surface 70a for electrical connection with the external substrate (motherboard). You may.

The present invention will be described with reference to examples. The present invention is not limited to the following examples.

(Making an adhesive film)
An acrylic copolymer was obtained by a solution polymerization method using the following main monomer and functional group monomer as the pressure-sensitive adhesive. That is, 2-ethylhexyl acrylate and methyl methacrylate were used as the main monomers, and hydroxyethyl acrylate and acrylic acid were used as the functional group monomers. The weight average molecular weight of the acrylic copolymer was 400,000, and the glass transition point was −38 ° C. A pressure-sensitive adhesive solution was prepared by blending 10 parts by mass of a polyfunctional isocyanate cross-linking agent (manufactured by Mitsubishi Chemical Corporation, trade name: Mytec NY730A-T) with 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 pressure-sensitive adhesive thickness at the time of drying was 10 μm. Further, a polyolefin base material (thickness 100 μm) made of polypropylene / vinyl acetate / polypropylene was laminated on the pressure-sensitive adhesive surface. As a result, an adhesive film composed of an adhesive layer and a polyolefin base material (base material layer) was obtained. This adhesive film was left at room temperature for 2 weeks for sufficient aging.

<Example 1>
(Preparation of adhesive varnish)
The following materials were mixed and vacuum degassed to obtain an adhesive varnish.
-Epoxy resin: HTR-860P-3 (trade name, manufactured by Nagase ChemteX Corporation, glycidyl group-containing acrylic rubber, molecular weight: 1 million, Tg: -7 ° C) 100 parts by mass-Heat-curing component: Millex XLC- LL (trade name, manufactured by Mitsui Chemicals, Inc., phenol aralkyl resin, hydroxyl weight equivalent 174) 17 parts by mass, thermosetting component: YDCN-700-10 (trade name, manufactured by Nippon Steel & Sumitomo Metal Corporation, o-cresol novolac 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: Aerodil R972 (trade name, Nippon Aerodil) Manufactured by Co., Ltd., silicon oxide, true spherical silica, average particle size of about 0.16 μm) 12 parts by mass ・ Additive (silane coupling agent): Appropriate amount ・ Solvent (cyclohexanone): Appropriate amount

(Manufacturing of tape for semiconductor processing)
The adhesive varnish was applied onto a surface release-treated polyethylene terephthalate (Teijin DuPont Film Co., Ltd., Teijin Tetron Film: A-31) having a thickness of 75 μm. As a result, an adhesive sheet having an adhesive layer formed on one surface of the resin film was obtained. By adhering this adhesive sheet and the above-mentioned adhesive film, a semiconductor processing tape was obtained. The adhesive sheet and the adhesive film were bonded so that the adhesive layer of the adhesive sheet and the adhesive layer of the adhesive film were in direct contact with each other. Since the adhesive layer is adhered to the adhesive layer, the adhesive layer formed of the polyethylene terephthalate can be reliably inverted toward the adhesive layer side.

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

(Comparative Example 1)
A semiconductor processing tape was obtained in the same manner as in Example 1 except that each material used for preparing the adhesive varnish had the composition shown in Comparative Example 1 in Table 1. In addition, "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 semiconductor processing tape was obtained in the same manner as in Example 1 except that each material used for preparing the adhesive varnish had the composition shown in Comparative Example 2 in 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 Co., Ltd., and "YDF-8170C" is Nippon Steel & Sumitomo Metal Corporation. Is a trade name of a thermosetting resin (bisphenol F type epoxy resin, epoxy equivalent 157) manufactured by Admatex Co., Ltd., and "SC-2050-HLG" is a trade name of a filler manufactured by Admatex Co., Ltd.

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

The semiconductor processing tapes according to Examples and Comparative Examples were evaluated by the following methods.
(1) Storage elastic modulus of the adhesive layer after the curing treatment The semiconductor processing tapes according to Examples and Comparative Examples were cut into sizes of 100 mm × 100 mm, respectively. The adhesive film (adhesive layer and base material layer) and the surface release-treated polyethylene terephthalate were peeled off from each sample to form only an adhesive layer, which was used as a sample for measurement. The measurement samples according to Examples and Comparative Examples were heated at 170 ° C. for 1 hour to be cured. The elastic modulus of the sample after the curing treatment was measured using a dynamic viscoelasticity measuring device DVE-V4 (trade name, manufactured by Rheology Co., Ltd.) under a tensile load, with a frequency of 10 Hz and a temperature rise rate of 10 ° C./min. The temperature was measured from −50 ° C. to 300 ° C. From the results, the storage elastic modulus at temperatures of 80 ° C. and 120 ° C. was determined. In Table 1, the sample having a storage elastic modulus of 7 MPa or less was designated as “A”, and the sample having a storage elastic modulus of more than 7 MPa was designated as “B”.

(2) 90 ° peel peeling force of the adhesive layer to the wafer (evaluation of adhesion to the wafer)
The cured sample used for the evaluation of the storage elastic modulus was cut into a width of 10 mm and used as a measurement sample. The measurement sample was attached to the surface of the silicon wafer. Then, an adhesive tape (auxiliary tape) was attached 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, the sample having a 90 ° peel peeling force value of 8 N / m or more was designated as “A”, and the sample having a value of less than 8 N / m was designated as “B”.

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

Claims (5)

Substrate layer and
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 and
A release film provided on the surface of the adhesive layer and
Is a semiconductor processing tape that is equipped with in this order.
After being cured at 170 ° C. for 1 hour, the adhesive layer has a storage elastic modulus at 80 ° C. of 1 MPa or more and 7 MPa or less, and a peel peeling force with respect to the wafer of 8 N / m or more and 30 N / m or less. ,
The adhesive layer contains a (meth) acrylic monomer having an epoxy group as a copolymerization component, and is a thermoplastic resin which is an epoxy group-containing (meth) acrylic copolymer having a weight average molecular weight of 500,000 or more and 2 million or less. Contains at least a thermosetting resin and a filler,
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 10 parts by mass or more and 37 parts by mass or less, and the filler in the adhesive layer. A tape for semiconductor processing having a content of 10 parts by mass or more and 100 parts by mass or less . The semiconductor processing tape according to claim 1, wherein the adhesive layer has a storage elastic modulus of 7 MPa or less at 120 ° C. after being cured at 170 ° C. for 1 hour. The adhesive layer further contains a curing accelerator and contains
According to claim 1 or 2, when the content of the thermoplastic resin in the adhesive layer is 100 parts by mass, the content of the curing accelerator in the adhesive layer is 0.01 parts by mass or more and 3 parts by mass or less. The described tape for semiconductor processing. The semiconductor processing according to any one of claims 1 to 3, wherein the base material layer, the adhesive layer, the adhesive layer, and the release film do not remain in the finally manufactured semiconductor device. Tape for. The semiconductor processing tape according to any one of claims 1 to 4, wherein the thermosetting resin contains an o-cresol novolak type epoxy resin and a phenol aralkyl resin.

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