JP2012164890A - Adhesive sheet for semiconductor, semiconductor wafer using the same, semiconductor device and semiconductor device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive sheet for a semiconductor; which has a function as a dicing tape such as a retention capacity of a semiconductor in a dicing process and adhesion to a wafer ring in transportation or expansion; which is capable of easy pickup; which represents excellent thermal fluidity and connection reliability when a semiconductor element and a support member or semiconductor elements are bonded; and which can be easily separated from the wafer ring after use.SOLUTION: An adhesive sheet of the present invention comprises: a base material (b) having a storage elastic modulus at 25°C of 50-1000 MPa; and an adhesive layer (a) including at least a thermoplastic resin and a thermosetting resin, having a thickness of not greater than 40 μm and laminated on the base material (b). A peel strength between the adhesive layer (a) and the base material (b) is 30-200 mN/cm.

Description

  The present invention relates to a semiconductor adhesive sheet, a semiconductor wafer using the same, a semiconductor device, and a method for manufacturing the semiconductor device.

  Conventionally, a silver paste has been mainly used for joining a semiconductor element and a semiconductor element mounting support member. However, with the recent increase in the size of semiconductor elements and the reduction in size and performance of semiconductor packages, the support members used are also required to be reduced in size and density.

  In response to such demands, the silver paste has the above-described wettability, defects due to wire bonding caused by protrusion and inclination of the semiconductor element, difficulty in controlling the thickness of the silver paste, and voids in the silver paste. It is becoming impossible to meet the demand. For this reason, in order to cope with the above demand, in recent years, a film-like adhesive has been used (see, for example, Patent Document 1 and Patent Document 2).

  This adhesive sheet is used in an individual sticking method or a wafer back surface sticking method. When manufacturing a semiconductor device using the former adhesive sheet of the individual piece pasting method, first, a reel-like adhesive sheet is cut into individual pieces by cutting or punching, and then adhered to a support member, with the adhesive sheet The semiconductor element separated into pieces by the dicing process is joined to the support member to produce a support member with a semiconductor element. Thereafter, a semiconductor device is obtained through a wire bonding process, a sealing process, and the like (see, for example, Patent Document 3). However, in order to use the adhesive sheet of the above-mentioned individual sticking method, a dedicated assembly device that cuts out the adhesive sheet and adheres it to the support member is necessary, so that the manufacturing cost is compared with the method using silver paste. There was a problem that became high.

  On the other hand, when manufacturing a semiconductor device using an adhesive sheet of a wafer back surface bonding method, first, one surface of the adhesive sheet is bonded to the back surface of the semiconductor wafer, and then a dicing sheet (adhesive sheet) is bonded to the other surface of the adhesive sheet. . Thereafter, the semiconductor element is separated from the wafer by dicing, the separated semiconductor element with an adhesive sheet is picked up, joined to a support member, and then subjected to subsequent steps such as wire bonding and sealing, A semiconductor device is obtained. This wafer back surface bonding type adhesive sheet joins a semiconductor element with an adhesive sheet to a support member, so that an apparatus for separating the adhesive sheet is not required, and a conventional silver paste assembling apparatus is used as it is or a heating plate. It can be used by improving a part of the apparatus, such as adding. For this reason, it has been attracting attention as a method in which the manufacturing cost can be kept relatively low among the assembling methods using an adhesive sheet (see, for example, Patent Document 4).

  However, in the method using the adhesive sheet of the wafer back surface pasting method, two pasting steps such as the step of applying the adhesive sheet and the step of pasting the dicing tape (adhesive sheet) are necessary before the dicing step. Therefore, simplification of the work process has been demanded.

  Moreover, the method of attaching an adhesive sheet on a dicing sheet (adhesive sheet) and sticking this on a wafer is proposed (for example, refer patent documents 5-7). In these methods, there is a problem that the resin of the dicing sheet (adhesive sheet) adheres to the adhesive sheet, or the adhesiveness decreases due to diffusion and migration, and the structure is dicing substrate, dicing sheet adhesive. The cost is increased because of the three-layer structure of the layer and the die bond layer.

  Therefore, an adhesive sheet that simplifies the manufacturing process of the semiconductor device and reduces manufacturing costs, that is, a die bonding sheet (viscosity) that acts as a dicing sheet in the dicing process and has excellent connection reliability in the bonding process between the semiconductor element and the support member. Adhesive sheet) has been demanded. Moreover, the further improvement of the reliability of an adhesive sheet was calculated | required.

  In order to solve these problems, a die bond film (adhesive sheet) containing an acrylic rubber component and a radiation polymerizable compound has been proposed (see, for example, Patent Document 8). Such a material acts as a dicing sheet in the dicing process, and thereafter, by performing radiation irradiation, the adhesiveness with the base material is lowered and pickup can be performed.

Japanese Patent Laid-Open No. 3-192178 JP-A-4-234472 Japanese Patent Laid-Open No. 9-17810 Japanese Patent Laid-Open No. 4-196246 JP 2002-226996 A JP 2002-158376 A Japanese Patent Laid-Open No. 02-032187 Japanese Patent No. 3912076

  In recent years, it has been required to further reduce the thickness of the adhesive sheet for semiconductors as electronic components have been reduced in size and height, and accordingly, further fluidity during heat has been required. However, the method of reducing the adhesion by performing radiation irradiation and crosslinking the radiation-polymerizable compound as described above has sufficient thermal fluidity (thermocompression bonding) and low adhesion to the substrate after irradiation. It was difficult to achieve both (pickup properties). Furthermore, in order to sufficiently reduce the adhesion after irradiation, the design includes many liquid radiation-polymerizable compounds and photoinitiators, so that storage stability such as bleed out and bleed in a roll state, wafer ring, There was a problem in the standing stability after lamination, such as adhesion to the wafer. Moreover, it was difficult to adhere to a substrate having irregularities without a gap.

  In view of the above-described problems of the prior art, the present invention has functions as a dicing tape, such as semiconductor chip retention in a dicing process and wafer ring adhesion at the time of transportation and expansion, and can be easily picked up. The present invention provides a semiconductor adhesive sheet that exhibits excellent thermal fluidity and connection reliability when joining a semiconductor element and a support member or semiconductor elements, and can be easily peeled off from a wafer ring after use. Objective. Another object of the present invention is to provide a semiconductor wafer and a semiconductor device using the semiconductor adhesive sheet. Moreover, an object of this invention is to provide the manufacturing method of the semiconductor device which can simplify a manufacturing method using the said adhesive bond sheet for semiconductors.

  The inventors of the present invention have intensively studied to solve the above problems, and as a result, have come to provide the following solutions.

  The adhesive sheet for semiconductor according to the present invention contains at least a base material (b) having a storage elastic modulus at 25 ° C. of 50 to 1000 MPa, (A) a thermoplastic resin, and (B) a thermosetting resin. The adhesive layer (a) having a thickness of 40 μm or less and laminated on the substrate (b), and peeling the adhesive layer (a) and the substrate (b). The strength (Y) is 30 to 200 mN / cm.

  The adhesive sheet for semiconductors of the present invention has an adhesive layer (2) containing at least (A) a thermoplastic resin and (B) a thermosetting resin. Can be made compatible. Moreover, the adhesive sheet for semiconductors of the present invention has a base material (b) having a storage elastic modulus at 25 ° C. of 50 to 1000 MPa, so that blade wear during dicing can be suppressed, and expandability during pick-up. Excellent. Moreover, in the adhesive sheet | seat for semiconductors of this invention, when the peeling strength (Y) of an adhesive layer (a) and a base material (b) is 30-200 mN / cm, it is in a dicing process. It is possible to achieve both semiconductor chip retention and pickup properties.

  The “peel peel strength (Y) between the adhesive layer (a) and the base material (b)” may be measured as follows. Adhesive adhesive layer (a) and base material (b) (adhesive layer thickness 10 μm) prepared in a 1 cm width strip shape at a predetermined temperature to a silicon wafer (thickness 400 μm) A sample is prepared by making the agent layer the silicon wafer side and pressurizing with a roll (linear pressure 4 kgf / cm, feed rate 0.5 m / min). Peel peel strength is the maximum value obtained by measuring the 90-degree tensile strength against the adhesive layer by fixing the sample base material part with the jig partly peeled off the sample base material. (Y). As a measuring device, Strograph ES (peeling speed 50 mm / min, 25 ° C.) manufactured by Toyo Seiki Seisakusho Co., Ltd. may be used.

  The “storage elastic modulus at 25 ° C.” can be measured, for example, as follows. The substrate is cut into a strip of 5 mm width, and using a viscoelasticity analyzer “RSA-2” (trade name) manufactured by Rheometrics, the heating rate is 5 ° C./min, the frequency is 1 Hz, and the measurement temperature is −50 to 100 ° C. The storage elastic modulus at 25 ° C. is measured under the following conditions.

  In the present invention, from the viewpoint of adhesion between the base material (b) and the adhesive layer (a) at the time of dicing, the surface free energy of the surface in contact with the adhesive layer of the base material is 25 to 45 mN. / m is preferable. Thereby, it becomes possible to control the adhesiveness between the base material (b) and the adhesive layer (a) to an adhesive strength that can achieve both dicing properties and pickup properties. Moreover, it becomes possible to bond to a base material (b) at low temperature, and the curvature of an adhesive sheet can be suppressed. Furthermore, it becomes possible to control adhesion by the bonding temperature.

  In the said invention, it is preferable that the base material (b) at the time of dicing contains at least the polymer which has ester skeleton. The polymer having the ester skeleton can increase the surface energy of the substrate without impairing the heat resistance of the substrate, and can improve the adhesion strength with the adhesive layer.

In the present invention, the substrate preferably contains at least a polymer having a polybutylene terephthalate skeleton represented by the following general formula (23). By applying the polymer, it is possible to achieve both a high surface energy necessary for adhesion with an adhesive and an expandability necessary for pickup.

  Moreover, in the said invention, it is preferable that the said base material contains an ethylene vinyl acetate copolymer at least.

  In the present invention, the SUS of the adhesive layer (a) is used from the viewpoints of retainability of the adhesive sheet in the dicing process, wafer ring adhesion during transportation and expansion, and easy peeling of the wafer after use. It is preferable that the adhesion strength with respect to is 50 to 400 mN / cm.

  The “adhesive strength of the adhesive layer to SUS” may be measured as follows. An adhesive sheet (adhesive layer thickness 10 μm) prepared in a strip shape with a width of 1 cm and a length of 4 cm on an SUS304 plate (thickness 500 μm) at a temperature of 25 ° C., and the adhesive layer on the SUS side Then, pressurizing with a roll (linear pressure 4 kgf / cm, feed rate 0.5 m / min) to prepare a sample having a 2 cm length fixed to SUS. The maximum value of the values obtained by fixing the adhesive sheet portion of the obtained sample with a jig and measuring the 90-degree tensile strength against SUS is defined as the adhesion strength. As a measuring device, Strograph ES (peeling speed 500 mm / min, 25 ° C.) manufactured by Toyo Seiki Seisakusho Co., Ltd. may be used.

  In the present invention, the surface free energy of the adhesive layer (a) is preferably 15 to 30 mN / m from the viewpoint of easy release from the used wafer ring. As a result, even when it is brought into close contact with a member having a high surface energy such as wafer ring (SUS), it can be easily peeled off after use.

  In the present invention, (A) the thermoplastic resin is preferably a polyimide resin from the viewpoints of film formability, heat fluidity, heat resistance, adhesion to SUS, and high-temperature adhesiveness after thermosetting.

  In the present invention, from the viewpoint of the adhesiveness of the adhesive layer (a) to the base material (b), the low temperature stickability of the adhesive layer to the adherend, and the hot fluidity during thermocompression bonding. (A) The glass transition temperature of the thermoplastic resin is preferably 80 ° C. or lower, and the melt viscosity at 120 ° C. of the adhesive layer is preferably 20000 Pa · s or lower.

  “(A) Glass transition temperature of thermoplastic resin” means that (A) a thermoplastic resin layer prepared to have a film thickness of 20 μm is heated and laminated with a roll (linear pressure 4 kgf / cm, feed rate 0.5 m). The sample having a thickness of 200 μm was cut into a strip having a width of 5 mm, and the temperature rising rate was 5 ° C./min using a rheometrics viscoelasticity analyzer “RSA-2” (trade name). , Tan δ peak temperature when measured under conditions of frequency 1 Hz and measurement temperature −50 to 100 ° C.

  “Melt viscosity at 120 ° C.” was prepared by laminating a 20 μm adhesive layer and pressurizing with a roll (linear pressure 4 kgf / cm, feed rate 0.5 m / min, temperature 50 ° C.). The minimum value of the melt viscosity at 120 ° C. when a sample having a thickness of 200 μm is measured using a viscoelasticity measuring apparatus ARES (manufactured by Rheometrics Scientific F.E.). The measurement plate is a parallel plate having a diameter of 8 mm, the measurement conditions are a temperature increase of 5 ° C./min, the measurement temperature is −50 ° C. to 200 ° C., and the frequency is 1 Hz.

  In the present invention, it is preferable that the polyimide resin has a structure represented by the following general formula (A) from the viewpoint that both film formability, thermal fluidity, pick-up property, and easy peeling from the wafer ring can be achieved. .

式（Ａ）中、Ｘは４価の有機基であり、ｎは３〜３０の整数である。

In formula (A), X is a tetravalent organic group, and n is an integer of 3 to 30.

  The semiconductor wafer according to the present invention is obtained by laminating the semiconductor adhesive sheet according to the present invention on a silicon wafer.

  The semiconductor device according to the present invention is bonded to each other using the semiconductor element and the semiconductor mounting support member and / or the semiconductor adhesive sheet that are bonded using the semiconductor adhesive sheet according to the present invention. A plurality of semiconductor elements.

  The method for manufacturing a semiconductor device according to the present invention is such that the adhesive layer (a) of the adhesive sheet for semiconductor according to the present invention is opposed to the semiconductor wafer and the wafer ring, and the base material (b) and the adhesive are bonded. The step of laminating the agent layer (a) on the semiconductor wafer and the wafer ring, and dicing the semiconductor wafer on which the base material (b) and the adhesive layer (a) are laminated, A step of obtaining a semiconductor chip with an adhesive layer (a), a step of obtaining a semiconductor chip with an adhesive layer (a) by picking up the separated semiconductor chip from the substrate (b) A step of pressure-bonding to a semiconductor element or a semiconductor mounting support member, and a step of peeling the substrate (b) and the adhesive layer (a) from the wafer ring.

  According to the present invention, it has a function as a dicing tape such as a semiconductor chip holding property in a dicing process and wafer ring adhesion at the time of transportation or expansion, and can be easily picked up, and a semiconductor element and a supporting member or Provided is an adhesive sheet for semiconductors that exhibits excellent thermal fluidity and connection reliability when bonding semiconductor elements, and can be easily peeled off from a wafer ring after use. In addition, according to the present invention, a semiconductor wafer and a semiconductor device using the semiconductor adhesive sheet are provided. Moreover, according to this invention, the manufacturing method of the semiconductor device which can simplify a manufacturing method using the said adhesive bond sheet for semiconductors is provided.

It is a schematic cross section of the adhesive sheet for semiconductors concerning one Embodiment of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings as necessary. However, the present invention is not limited to the following embodiments. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified, and the dimensional ratio in the drawing is not limited to the illustrated ratio.

(Adhesive sheet for semiconductors)
The adhesive sheet for semiconductors (adhesive film for semiconductors) of this embodiment contains at least (A) a thermoplastic resin and (B) a thermosetting resin and has a thickness of 40 μm or less. A pressure-sensitive adhesive sheet comprising a layer (a) and a base material (b) having a storage elastic modulus at 25 ° C. of 50 to 1000 MPa, wherein the peel between the adhesive layer (a) and the base material (b) The peel strength (Y) is 30 mN / cm to 200 mN / cm.

  The storage elastic modulus at 25 ° C. of the substrate (b) of this embodiment is 50 to 1000 MPa. Examples of such a substrate include polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyolefin such as polyethylene and polypropylene, and the like. Alternatively, a resin having a storage elastic modulus at 25 ° C. of 1 GPa or more may be mixed with a rubber component such as acrylic, butadiene, or nitrile to obtain the above elastic modulus. The storage elastic modulus of the substrate (b) at 25 ° C. is preferably 50 to 1000 MPa, preferably 50 to 800 MPa, and most preferably 100 to 600 MPa. The storage elastic modulus of the substrate (b) is measured in a state where the adhesive layer is not laminated.

  The surface free energy of the surface in contact with the adhesive layer (a) of the substrate (b) of the present embodiment is preferably 25 to 45 mN / m, and most preferably 30 to 45 mN / m. As the base material (b) having a surface energy in the above range, a polar base material such as polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, a low polarity base material such as polyethylene or polypropylene, a urethane type, an acrylic type, Examples include those obtained by blending rubber components such as butadiene and nitriles, and those obtained by corona-treating a low-polarity base material such as polyethylene or polypropylene. When the surface free energy is less than 25 mN / m, the adhesiveness with the adhesive layer (a) is lowered, and there is a tendency that the production yield is lowered due to transfer failure or the semiconductor chip is scattered during dicing. Moreover, when it exceeds 45 mN / m, there exists a tendency for adhesiveness with an adhesive agent layer to rise and for pick-up property to be impaired. Moreover, it is preferable not to perform a corona treatment on the surface in contact with the adhesive layer (a) from the viewpoints of storage stability and pickup properties.

  The substrate (b) preferably has at least a polymer having an ester skeleton. In addition to polyethylene terephthalate and polybutylene terephthalate, the polymer having an ester skeleton has an ester skeleton in the main chain, such as a polyester using an aliphatic carboxylic acid instead of terephthalic acid, or a polyester using a long-chain aliphatic diol. The polyester which has is mentioned. The long chain aliphatic represents an organic group having 3 to 30 carbon atoms. Moreover, the polymer which has an ester group in side chains, such as an ethylene-vinyl acetate copolymer and polymethyl methacrylate, is mentioned.

  The polymer having an ester group can be contained in a low surface energy base material such as polyethylene or polypropylene, and can achieve both desired surface energy and expandability.

  In this embodiment, a protective film can also be provided on the adhesive layer. Thereby, contamination of the adhesive layer, adhesion of the adhesive layer to the back surface of the substrate (b) when the adhesive sheet is rolled, physical damage to the adhesive layer Can be suppressed. It is preferable that the storage elastic modulus at 25 ° C. of the protective film is 1 GPa or more, and the surface free energy of the surface in contact with the adhesive layer (a) of the protective film is 10 to 25 mN / m. The protective film is preferably one that can withstand 80 to 150 ° C., which is a heating and drying condition during the production of the adhesive sheet. Examples of the protective film satisfying the above include polyester film, polypropylene film, polyethylene terephthalate film, polyimide film, polyetherimide film, polyether naphthalate film, and methylpentene film. Two or more of these protective films may be combined to form a multilayer film. In order to satisfy the surface energy, it is preferable to treat the surface of the protective film with a release agent such as silicone, acrylic, or silica. When the surface energy exceeds 25 mN / m, it is difficult to release the adhesive layer, and when it is less than 10 mN / m, it is difficult to form a pressure-sensitive adhesive layer.

  The thickness of the adhesive layer of this embodiment is preferably 40 μm or less, more preferably 20 μm or less, and further preferably 10 μm or less from the viewpoint of miniaturization and low profile of the semiconductor device. More preferably, it is most preferably 7 μm or less. Moreover, it is preferable that the thickness of an adhesive agent layer is 1 micrometer or more. When the thickness is less than 1 μm, it becomes difficult to impart hot fluidity, and voids tend to occur during thermocompression bonding.

  The adhesive strength of the adhesive layer of the present embodiment to SUS (SUS wafer ring) is the adhesiveness of the adhesive sheet in the dicing process, the wafer ring adhesiveness during transport and expansion, and the wafer ring after use. From the viewpoint of easy release, it is preferably 50 to 400 mN / cm, more preferably 80 to 300 mN / cm, and most preferably 100 to 250 mN / cm. When the adhesion strength to SUS is less than 50 mN / cm, the adhesive layer tends to peel off from the wafer ring during the dicing step, during conveyance, or during expansion. If it exceeds 400 mN / cm, the adhesive layer tends not to peel from the wafer ring after use, and the resin tends to remain.

  In order to achieve high compatibility between semiconductor chip retention and pick-up properties in the dicing process, the peel peel strength (Y) between the adhesive layer (a) and the base material (b) is 30 to 200 mN / cm. Is more preferably 35 to 150 mN / cm, and most preferably 40 to 120 mN / cm.

  Achieving high compatibility between film formability and easy peelability for the base material (b) of the adhesive layer, peelability from the wafer ring after use, lamination to silicon wafers, thermocompression bonding, and high temperature adhesion In order to satisfy the above, the surface free energy of the adhesive layer (a) is preferably 15 to 30 mN / m, more preferably 17 to 27 mN / m, and 20 to 25 mN / m. Most preferred. When the surface free energy is less than 15 mN / m, there is a tendency that the adhesiveness such as laminating property to the silicon wafer, the thermocompression bonding property to the adherend, and the high temperature adhesiveness are lowered, and when it exceeds 30 mN / m, the film formability is increased. There exists a tendency for it to fall or to peel from the wafer ring after use.

  The surface free energy of the adhesive layer (a) is a contact angle meter (DropMaster 500, manufactured by Kyowa Interface Science Co., Ltd.) when water, glycerin and formamide are used as probe liquids for the adhesive layer. Is measured at an appropriate amount of 1 μL at a measurement temperature of 25 ° C., and may be determined by an acid-base method using analysis software (FAMAS, manufactured by Kyowa Interface Science Co., Ltd.) mounted on a contact angle meter.

  The glass transition temperature of the adhesive layer of this embodiment is preferably 80 ° C. or lower, and more preferably 60 ° C. or lower. Further, the melt viscosity at 120 ° C. of the adhesive layer is preferably 20000 Pa · s or less, and more preferably 10000 Pa · s or less. When the glass transition temperature exceeds 80 ° C., it is necessary to carry out heating at 80 ° C. or higher when transferring to the substrate (b), warping of the adhesive sheet occurs, and the substrate and the adhesive layer (a ) Tends to peel off. Also, when laminating on the back side of the wafer, it is necessary to heat at 80 ° C. or higher, and the warpage of the wafer tends to increase. Also, if the melt viscosity at 120 ° C. exceeds 20000 Pa · s, voids are likely to be generated during thermocompression bonding, reducing the reliability of the semiconductor device, and thermocompression bonding is particularly difficult when the adhesive layer is 10 μm or less. Tend to be. When the thermocompression bonding temperature is increased, thermal damage to other members tends to increase or the energy required for manufacturing the semiconductor device tends to increase. The sticking temperature of the adhesive sheet to the back surface of the wafer is preferably 20 to 150 ° C. and more preferably 40 to 80 ° C. from the viewpoint of suppressing warpage of the semiconductor wafer. In order to enable attachment at the above temperature, the glass transition temperature Tg of the adhesive layer is preferably 80 ° C. or lower. On the other hand, if Tg is less than −20 ° C., the tackiness of the film surface in the B-stage state becomes too strong, and the handleability tends to be poor.

  The storage elastic modulus at 180 ° C. after thermosetting the adhesive layer (a) of this embodiment is preferably 10 MPa or more, more preferably 20 MPa or more, and most preferably 50 MPa or more. preferable. When the storage elastic modulus at 180 ° C. is less than 10 MPa, the high-temperature adhesiveness tends to be lowered and the reliability tends to be lowered, or the chip cannot be held at the time of wire bonding.

  The Tg of the (A) thermoplastic resin used in the present embodiment is preferably 80 ° C. or less, and most preferably 60 ° C. or less. When this Tg exceeds 80 ° C., a high temperature of 80 ° C. or more is required when the adhesive layer (a) is bonded to the adherend (semiconductor wafer), and the semiconductor wafer tends to be warped. is there.

  Here, “Tg” means (A) the main dispersion peak temperature when the thermoplastic resin is formed into a film. Using a rheometrics viscoelasticity analyzer “RSA-2” (trade name), the film thickness is 100 μm, the heating rate is 5 ° C./min, the frequency is 1 Hz, and the measurement temperature is −50 to 200 ° C. Is the main dispersion peak temperature.

  (A) It is preferable that the weight average molecular weight of the thermoplastic resin is controlled within a range of 10,000 to 500,000, and is 20000 to 300,000 in that both low temperature sticking property, thermocompression bonding property and high temperature adhesiveness are highly compatible. More preferably, it is more preferably 30000 to 200000 in terms of further improving the adhesion to the substrate (a). When the weight average molecular weight is within the above range, the strength and flexibility of the adhesive layer (b) are improved, so that good film formability is obtained, and the adhesive is used from the wafer ring after use. Layer (b) can be peeled off without breaking. Further, since the thermal fluidity is good, it is possible to ensure good embedding properties with respect to the wiring step (unevenness) on the substrate surface. If the weight average molecular weight is less than 10,000, the film formability tends to be insufficient, and the adhesive layer (b) tends to break easily. On the other hand, when the weight average molecular weight exceeds 500,000, there is a tendency that the hot fluidity and the embedding property are not sufficient and the adhesion to the substrate (a) is not sufficient. Here, the “weight average molecular weight” is the weight average molecular weight when measured in terms of polystyrene using dimethylformamide as a solvent using high performance liquid chromatography “C-R4A” (trade name) manufactured by Shimadzu Corporation. means.

  In order to achieve both good film-forming properties and adhesiveness and peelability, the (A) thermoplastic resin preferably has a silicone skeleton.

  (A) As a thermoplastic resin, polyester resin, polyether resin, polyimide resin, polyamide resin, polyamideimide resin, polyetherimide resin, polyurethane resin, polyurethaneimide resin, polyurethaneamideimide resin, siloxane polyimide resin, polyesterimide resin In addition to these copolymers and their precursors (polyamide acid, etc.), polybenzoxazole resin, phenoxy resin, polysulfone resin, polyethersulfone resin, polyphenylene sulfide resin, polyester resin, polyether resin, polycarbonate resin, poly Examples thereof include ether ketone resins, (meth) acrylic copolymers having a weight average molecular weight of 10,000 to 1,000,000, novolac resins, and phenol resins. These can be used individually by 1 type or in combination of 2 or more types. In addition, the main chain and / or side chain of these resins may be provided with a glycol group such as ethylene glycol or propylene glycol, a carboxyl group, and / or a hydroxyl group.

  (A) The thermoplastic resin is not particularly limited. For example, dimethylformamide, toluene, benzene, xylene, methyl ethyl ketone, tetrahydrofuran, ethyl cellosolve, ethyl cellosolve acetate, dioxane, cyclohexanone, ethyl acetate, and N-methyl-pyrrolidinone. It is preferable to use a resin that can be dissolved in a solvent selected from any of these to form a film.

  Among these, it is preferable that (A) the thermoplastic resin is a polyimide resin from the viewpoints of high-temperature adhesiveness, heat resistance, and film formability. The polyimide resin can be obtained, for example, by subjecting tetracarboxylic dianhydride and diamine to a condensation reaction by a known method. That is, in the organic solvent, tetracarboxylic dianhydride and diamine are equimolar, or if necessary, the total amount of diamine is preferably 0.00 with respect to the total 1.0 mol of tetracarboxylic dianhydride. The composition ratio is adjusted in the range of 5 to 2.0 mol, more preferably 0.8 to 1.0 mol (the order of addition of each component is arbitrary), and the addition reaction is performed at a reaction temperature of 80 ° C. or lower, preferably 0 to 60 ° C. . As the reaction proceeds, the viscosity of the reaction solution gradually increases, and polyamic acid, which is a polyimide resin precursor, is generated. In addition, in order to suppress the fall of the various characteristics of a resin composition, it is preferable that said tetracarboxylic dianhydride is what recrystallized and refined with acetic anhydride.

  About the composition ratio of tetracarboxylic dianhydride and diamine in the condensation reaction, when the total of diamine exceeds 2.0 mol with respect to the total 1.0 mol of tetracarboxylic dianhydride, The amount of amine-terminated polyimide oligomer tends to increase, the weight average molecular weight of the polyimide resin decreases, and various properties including the heat resistance of the resin composition tend to be insufficient. On the other hand, when the total of diamine is less than 0.5 mol with respect to the total of 1.0 mol of tetracarboxylic dianhydride, the amount of acid-terminated polyimide resin oligomer tends to increase, and the weight average molecular weight of the polyimide resin is increased. There is a tendency that various properties including the heat resistance of the resin composition are not sufficient.

  The polyimide resin can be obtained by dehydrating and ring-closing the reaction product (polyamic acid). Dehydration ring closure can be performed by a thermal ring closure method in which heat treatment is performed, a chemical ring closure method using a dehydrating agent, or the like.

  The polyimide resin in the present embodiment means a resin having an imide group. Specific examples include polyimide resins, polyamideimide resins, polyurethaneimide resins, polyetherimide resins, polyurethaneamideimide resins, siloxane polyimide resins, and polyesterimide resins, but are not particularly limited thereto.

  There is no restriction | limiting in particular as tetracarboxylic dianhydride used as a raw material of a polyimide resin, For example, pyromellitic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane Anhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) ) Methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 3,4,9,10-perylenetetracarbo Acid dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, 3,4,3 ′, 4′-benzophenone tetracarboxylic Acid dianhydride, 2,3,2 ′, 3′-benzophenone tetracarboxylic dianhydride, 3,3,3 ′, 4′-benzophenone tetracarboxylic dianhydride, 1,2,5,6-naphthalene Tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,4,5-naphthalenetetracarboxylic Acid dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2 , 3,6,7-tetrac Loronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-1,8,9,10-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride , Thiophene-2,3,5,6-tetracarboxylic dianhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride, 3,4,3 ′, 4′-biphenyltetracarboxylic Acid dianhydride, 2,3,2 ′, 3′-biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) dimethylsilane dianhydride, bis (3,4-dicarboxyphenyl) methyl Phenylsilane dianhydride, bis (3,4-dicarboxyphenyl) diphenylsilane dianhydride, 1,4-bis (3,4-dicarboxyphenyldimethylsilyl) benzene dianhydride, 1,3-bis ( , 4-Dicarboxyphenyl) -1,1,3,3-tetramethyldicyclohexane dianhydride, p-phenylenebis (trimellitic anhydride), ethylenetetracarboxylic dianhydride, 1,2,3,4- Butanetetracarboxylic dianhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1 , 2,5,6-tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, 1 , 2,3,4-cyclobutanetetracarboxylic dianhydride, bis (exo-bicyclo [2,2,1] heptane-2,3-dicarboxylic dianhydride, bicyclo- [2,2,2] -oct -7-D -2,3,5,6-tetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis [4- (3,4-dicarboxy) Phenyl) phenyl] propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bis [4- (3,4-dicarboxyphenyl) phenyl] hexa Fluoropropane dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 1,4-bis (2-hydroxyhexafluoroisopropyl) benzenebis (trimellitic anhydride), 1,3-bis (2-hydroxyhexafluoroisopropyl) benzenebis (trimellitic anhydride), 5- (2,5-dioxotetrahydrofuryl) -3- Til-3-cyclohexene-1,2-dicarboxylic dianhydride, tetrahydrofuran-2,3,4,5-tetracarboxylic dianhydride can be used, and film formability, glass transition temperature, substrate (b From the viewpoint of adhesiveness to tetracarboxylic dianhydride represented by the following general formula (1), etc. are preferably used. In the following general formula (1), a represents an integer of 2 to 20.

  The tetracarboxylic dianhydride represented by the general formula (1) can be synthesized from, for example, trimellitic anhydride monochloride and the corresponding diol, specifically 1,2- (ethylene) bis ( Trimellitate anhydride), 1,3- (trimethylene) bis (trimellitic anhydride), 1,4- (tetramethylene) bis (trimellitic anhydride), 1,5- (pentamethylene) bis (trimellitic anhydride), 1 , 6- (Hexamethylene) bis (trimellitic anhydride), 1,7- (heptamethylene) bis (trimellitic anhydride), 1,8- (octamethylene) bis (trimellitic anhydride), 1,9- (nonamethylene) ) Bis (trimellitic anhydride), 1,10- (decamethylene) bis (trimellitic anhydride), 1,12- (dodecamethylene) ) Bis (trimellitate anhydride), 1,16 (hexamethylene decamethylene) bis (trimellitate anhydride), 1,18 (octadecamethylene) bis (trimellitate anhydride) and the like.

  The above tetracarboxylic dianhydrides can be used singly or in combination of two or more.

  There is no restriction | limiting in particular as another diamine used as a raw material of the said polyimide resin, For example, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3,3'- diaminodiphenyl ether, 3,4'-diaminodiphenyl ether 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylethermethane, bis (4-amino-3,5-dimethylphenyl) methane, bis (4-amino-3,5-diisopropylphenyl) methane, 3,3'-diaminodiphenyldifluoromethane, 3,4'-diaminodiphenyldifluoromethane, 4,4'-diaminodiphenyldifluoromethane, 3,3'-diamino Diphenylsulfo 3,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfide, 3,4′-diaminodiphenylsulfide, 4,4′-diaminodiphenylsulfide, 3,3 ′ -Diaminodiphenyl ketone, 3,4'-diaminodiphenyl ketone, 4,4'-diaminodiphenyl ketone, 2,2-bis (3-aminophenyl) propane, 2,2 '-(3,4'-diaminodiphenyl) Propane, 2,2-bis (4-aminophenyl) propane, 2,2-bis (3-aminophenyl) hexafluoropropane, 2,2- (3,4'-diaminodiphenyl) hexafluoropropane, 2,2 -Bis (4-aminophenyl) hexafluoropropane, 1,3-bis (3-aminophenoxy) benze 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 3,3 ′-(1,4-phenylenebis (1-methylethylidene)) bisaniline, 3, 4 '-(1,4-phenylenebis (1-methylethylidene)) bisaniline, 4,4'-(1,4-phenylenebis (1-methylethylidene)) bisaniline, 2,2-bis (4- (3 -Aminophenoxy) phenyl) propane, 2,2-bis (4- (3-aminophenoxy) phenyl) hexafluoropropane, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, bis ( 4- (3-aminoenoxy) phenyl) sulfide, bis (4- (4-aminoenoxy) phenyl) sulfide, bis (4- (3-aminoenoxy) ) Phenyl) sulfone, bis (4- (4-aminoenoxy) phenyl) sulfone, 3,3′-dihydroxy-4,4′-diaminobiphenyl, aromatic diamines such as 3,5-diaminobenzoic acid, 1,3- Bis (aminomethyl) cyclohexane, 2,2-bis (4-aminophenoxyphenyl) propane, aliphatic ether diamine represented by the following general formula (8), siloxane diamine represented by the following general formula (9), etc. Can be mentioned.

Among the above diamines, aliphatic ether diamines represented by the following general formula (8) are preferable and ethylene glycol and / or propylene glycol diamines are more preferable in terms of imparting compatibility with other components and organic solvent solubility. . The aliphatic ether diamine is preferably contained in an amount of 10 to 80 mol% of the entire diamine. In the following general formula (8), R ¹ , R ² and R ³ each independently represent an alkylene group having 1 to 10 carbon atoms, and b represents an integer of 2 to 80.

  Specific examples of such aliphatic ether diamines include Jeffamine D-230, D-400, D-2000, D-4000, ED-600, ED-900, ED-2000, and EDR manufactured by Sun Techno Chemical Co., Ltd. -148, BASF (manufactured) polyetheramine D-230, D-400, D-2000 and other aliphatic diamines such as polyoxyalkylene diamine. These diamines are preferably 1 to 80 mol% of the total diamines, and are compatible with other compounding components, and also have a low temperature sticking property and a high compatibility between high temperature adhesiveness and high temperature adhesiveness. More preferably, it is mol%. If this amount is less than 1 mol%, it tends to be difficult to impart high-temperature adhesiveness and hot fluidity. On the other hand, if it exceeds 80 mol%, the Tg of the polyimide resin becomes too low, Self-supporting tends to be impaired.

In addition, as the diamine, a siloxane diamine represented by the following general formula (9) can be used in that both good film formability and peelability of the protective film can be achieved and satisfactory peelability from the wafer ring can be satisfied. It is preferable to contain. In the following general formula (9), R ⁴ and R ⁹ each independently represent an alkylene group having 1 to 5 carbon atoms or a phenylene group which may have a substituent, and R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represents an alkyl group having 1 to 5 carbon atoms, a phenyl group or a phenoxy group, and d represents an integer of 3 to 30. The diamine is preferably 1 to 50 mol% of the total diamine, more preferably 3 to 30 mol%, and most preferably 5 to 20 mol%. When the amount of siloxane diamine (9) is less than 1 mol%, the effect tends to be reduced. When the amount exceeds 50 mol%, compatibility with other components and thermocompression bonding are reduced, or 180 ° C. after thermosetting. Since the storage elastic modulus is lowered, the wire bondability is lowered, or the high-temperature adhesiveness is lowered and the reliability tends to be impaired.

  In the general formula (9), d is preferably 3 to 30, and more preferably 5 to 20. When d is 3 or less, the effect of reducing the surface energy of the polyimide resin is reduced. On the other hand, if it exceeds 30, the glass transition temperature of the polyimide resin becomes difficult to control, or the compatibility with other compounding components tends to be lowered and the varnish stability tends to be impaired.

  The diamine mentioned above can be used individually by 1 type or in combination of 2 or more types.

  Moreover, the said polyimide resin can be used individually by 1 type or in mixture (blend) of 2 or more types as needed.

  Moreover, a polyimide resin can introduce | transduce a phenolic hydroxyl group into a side chain, as shown by the following general formula (21). The 180 degreeC elasticity modulus and 260 degreeC adhesive strength after thermosetting an adhesive film can be improved by using the polyimide resin which has a phenolic hydroxyl group.

式（２１）中、Ｘは４価の有機基を示し、Ｒは、単結合、又は、２価の有機基を示す。

In formula (21), X represents a tetravalent organic group, and R represents a single bond or a divalent organic group.

Examples of the divalent organic group include, for example, a divalent hydrocarbon group having 1 to 30 carbon atoms, or a divalent carbon atom having 1 to 30 carbon atoms in which part or all of hydrogen has been substituted with a halogen atom. Hydrogen group, — (C═O) —, —SO ₂ —, —O—, —S—, —NH— (C═O) —, — (C═O) —O—, — (Ph) _n — , — (Ph—OH) _n — and the like. Here, Ph represents a benzene ring, and n represents an integer of 1 to 20.

  In order to obtain a phenolic hydroxyl group-containing polyimide resin, a diamine represented by the following general formula (A-1) can be used.

式（Ａ−１）中、Ｒ^２１は、単結合、又は、２価の有機基を示す。

In formula (A-1), R ²¹ represents a single bond or a divalent organic group.

Examples of the divalent organic group include, for example, a divalent hydrocarbon group having 1 to 30 carbon atoms, or a divalent carbon atom having 1 to 30 carbon atoms in which part or all of hydrogen has been substituted with a halogen atom. Hydrogen group, — (C═O) —, —SO ₂ —, —O—, —S—, —NH— (C═O) —, — (C═O) —O—, — (Ph) _n — , — (Ph—OH) _n — and the like. Here, Ph represents a benzene ring, and n represents an integer of 1 to 20.

R ²¹ is preferably —C (CF ₃ ) ₂ — or —C (CH ₃ ) ₂ — from the viewpoint of solubility of the polyimide resin. In the present embodiment, the diamine having a phenolic hydroxyl group preferably includes a diphenol diamine having a fluoroalkyl group represented by the following formula (22). By introducing a fluoroalkyl group into the polyimide chain, the solubility of the polyimide resin in the solvent and other components is improved.

  By adding a monofunctional acid anhydride and / or a monofunctional amine such as a compound represented by the following general formula (10), (11) or (12) to the condensation reaction solution during the synthesis of the polyimide resin, Functional groups other than acid anhydrides or diamines can be introduced at the polymer terminals. Thereby, storage stability and thermocompression bonding can be improved. Although it does not specifically limit as functional groups other than an acid anhydride or diamine, A carboxyl group and a phenolic hydroxyl group are preferable at the point which improves high temperature adhesiveness. In addition, a compound having a siloxane skeleton or the like is also preferably used from the viewpoint that both good film formability and peelability of the protective film can be achieved, and satisfactory peelability from the wafer ring can be satisfied.

  (A) The content of the thermoplastic resin is preferably 5 to 90 mass%, more preferably 20 to 80 mass%, based on the total solid content of the resin composition. When this content is less than 5% by mass, the film formability tends to be insufficient, and when it exceeds 90% by mass, the adhesion tends to be insufficient.

  The adhesive layer (a) of this embodiment contains (B) thermosetting resin. As an epoxy resin, what contains at least 2 or more epoxy group in a molecule | numerator is preferable, and the point of the thermocompression bonding property, sclerosis | hardenability, and hardened | cured material property is more preferable. Examples of such resins include bisphenol A type (or AD type, S type, and F type) glycidyl ether, water-added bisphenol A type glycidyl ether, ethylene oxide adduct bisphenol A type glycidyl ether, and propylene oxide adduct. Bisphenol A type glycidyl ether, phenol novolac resin glycidyl ether, cresol novolac resin glycidyl ether, bisphenol A novolac resin glycidyl ether, naphthalene resin glycidyl ether, trifunctional (or tetrafunctional) glycidyl ether, dicyclo Examples include glycidyl ether of pentadienephenol resin, glycidyl ester of dimer acid, trifunctional (or tetrafunctional) glycidylamine, glycidylamine of naphthalene resin, etc. It is. These can be used alone or in combination of two or more.

  As the epoxy resin, it is possible to use a high-purity product in which impurity ions such as alkali metal ions, alkaline earth metal ions, halogen ions, particularly chlorine ions and hydrolyzable chlorine are reduced to 300 ppm or less. From the viewpoint of prevention and corrosion prevention of metal conductor circuits.

  It is preferable that it is 30-300 mass parts with respect to 100 mass parts of (A) thermoplastic resins, and, as for content of an epoxy resin, it is more preferable that it is 50-200 mass parts. When this content exceeds 300 parts by mass, the film formability tends to be reduced, or the toughness of the film is lowered and the film tends to break when it is peeled off from the wafer ring. On the other hand, when the content is less than 30 parts by mass, there is a tendency that sufficient tackiness, thermocompression bonding, and high-temperature adhesiveness cannot be obtained.

  The (B) thermosetting resin of this embodiment preferably includes both (B1) a solid epoxy resin and (B2) a liquid epoxy resin.

  (B1) The solid epoxy resin is not particularly limited. For example, bisphenol A type (or AD type, S type, F type) glycidyl ether, glycidyl ether of phenol novolac resin, glycidyl ether of cresol novolac resin, bisphenol A Examples thereof include glycidyl ether of novolak resin, glycidyl ether of naphthalene resin, trifunctional (or tetrafunctional) glycidyl ether, glycidyl ether of dicyclopentadienephenol resin, etc., adhesion to substrate (b), high temperature It is most preferable to use an epoxy resin represented by the following structure (I) or (II) from the viewpoint that the adhesiveness and the 180 ° C. storage elastic modulus after curing can be highly satisfied.

式（Ｉ）中、ｎは０〜５の整数である。

In formula (I), n is an integer of 0-5.

  (B1) Although it does not specifically limit as a liquid epoxy resin, For example, glycidyl ether of bisphenol A type (or AD type, S type, F type), glycidyl ether of water addition bisphenol A type, ethylene oxide adduct bisphenol A type Examples include glycidyl ether, propylene oxide adduct bisphenol A type glycidyl ether, naphthalene resin glycidyl ether, trifunctional (or tetrafunctional) glycidylamine, etc., adhesion to substrate (b), high temperature adhesion It is most preferable to use an epoxy resin represented by the following structure (III) from the viewpoint that the 180 ° C. storage elastic modulus after curing is highly satisfactory.

  Examples of the curing agent include phenolic compounds, aliphatic amines, alicyclic amines, aromatic polyamines, polyamides, aliphatic acid anhydrides, alicyclic acid anhydrides, aromatic acid anhydrides, dicyandiamide, and organic acid dihydrazides. , Boron trifluoride amine complexes, imidazoles, tertiary amines and the like. Among these, phenol compounds are preferable, and phenol compounds having at least two phenolic hydroxyl groups in the molecule are more preferable. Examples of such compounds include phenol novolak, cresol novolak, t-butylphenol novolak, dicyclopentadiene cresol novolak, dicyclopentadiene phenol novolak, xylylene-modified phenol novolak, naphthol compound, trisphenol compound, tetrakisphenol novolak, bisphenol. A novolak, poly-p-vinylphenol, phenol aralkyl resin and the like. Among these, those having a number average molecular weight in the range of 400 to 4000 are preferable.

  It is preferable that the adhesive layer (a) of this embodiment contains (C) a hardening accelerator. (C) The curing accelerator contains a curing accelerator that accelerates the curing / polymerization of epoxy by heating. Examples thereof include imidazoles, dicyandiamide derivatives, dicarboxylic acid dihydrazide, triphenylphosphine, and tetraphenylphosphonium tetraphenyl. Examples thereof include borate, 2-ethyl-4-methylimidazole-tetraphenylborate, 1,8-diazabicyclo [5.4.0] undecene-7-tetraphenylborate. As for content of the hardening accelerator in a composition, 0.01-50 mass parts is preferable with respect to 100 mass parts of epoxy resins.

  (C) The curing accelerator is preferably an imidazole having a melting point of 30 ° C. or higher, and most preferably 100 ° C. or higher, from the viewpoint of suppressing reaction during film coating and storage stability. . Examples of such imidazoles include, but are not limited to, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl (1 ')]-Ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl (1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2 -Phenyl-4-methyl-5-hydroxymethylimidazole and the like.

  The (C) curing accelerator is preferably used after being pulverized to 5 μm or less in order to suppress unevenness during the formation of the thin film.

  A radiation-polymerizable compound can also be added to the adhesive layer (a) of this embodiment. Examples of the radiation polymerizable compound include compounds having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, and a nadiimide. Group, a (meth) acryl group, and the like, and a (meth) acryl group is preferable from the viewpoint of reactivity. Among them, urethane acrylates and methacrylates, isocyanuric acid di / triacrylates and methacrylates, and imide group-containing monofunctional (meth) acrylates such as 2- (1,2-cyclohexacarboxyimide) ethyl acrylate are adhesive and highly adhesive after curing. It is preferable at the point which can fully provide property.

  A photoinitiator can be added to the adhesive layer (a) of this embodiment in order to improve the pickup property. As the photoinitiator, those having a molecular extinction coefficient with respect to light having a wavelength of 365 nm are preferably 100 ml / g · cm or more, more preferably 200 ml / g · cm or more, more preferably 400 ml / g · cm from the viewpoint of improving sensitivity. What is more than cm is even more preferable, and what is more than 1000 ml / g · cm is most preferable. As for the molecular extinction coefficient, a 0.001% by mass acetonitrile solution of the sample is prepared, and the absorbance of this solution is measured using a spectrophotometer (manufactured by Hitachi High-Technologies Corporation, “U-3310” (trade name)). Is required.

  Examples of such a photoinitiator include 1-hydroxy-cyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 1- [4- (2-hydroxyethoxy) -phenyl. ] -2-Hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane-1 -One, oxy-phenyl-acetic acid 2- [2-oxo-2-phenyl-acetoxy-ethoxy] ethyl ester, phenylglyoxylic acid methyl ester, 2-dimethylamino-2- (4-methyl-benzyl) -1 -(4-morpholin-4-yl-phenyl) -butan-1-one, 2-ethylhexyl -Dimethylaminobenzoate, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl- Aromatic ketones such as phenyl-ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropanone-1,2,4-diethylthioxanthone, 2-ethylanthraquinone, phenanthrenequinone, benzyldimethyl ketal Benzyl derivatives such as 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- ( o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-meth) Cyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer , 2,4,5-triarylimidazole dimer such as 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine, 1,7-bis (9, Acridine derivatives such as 9'-acridinyl) heptane, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, bis (2,4,6, -trimethylbenzoyl) -phenylphosphine Examples thereof include bisacylphosphine oxides such as oxides and compounds having maleimide. These can be used alone or in combination of two or more.

  Furthermore, in this embodiment, a filler can also be used. Examples of the filler include metal fillers such as silver powder, gold powder, copper powder, and nickel powder, alumina, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, and magnesium oxide. Inorganic fillers such as aluminum oxide, aluminum nitride, crystalline silica, amorphous silica, boron nitride, titania, glass, iron oxide, and ceramics, and organic fillers such as carbon and rubber fillers. It can be used without any particular limitation.

  The filler can be used properly according to the desired function. For example, the metal filler is added for the purpose of imparting conductivity, thermal conductivity, thixotropy, etc. to the adhesive composition, and the nonmetallic inorganic filler is thermally conductive, low thermal expansion, low hygroscopicity to the adhesive layer. The organic filler is added for the purpose of imparting toughness to the adhesive layer. These metal fillers, inorganic fillers or organic fillers can be used alone or in combination of two or more. Among them, a metal filler, an inorganic filler, or an insulating filler is preferable, and an inorganic filler or an insulating filler is preferable in that it can provide conductivity, thermal conductivity, low moisture absorption characteristics, insulating properties, and the like required for an adhesive material for a semiconductor device. Among the fillers, boron nitride is more preferable because it has good dispersibility with respect to the resin varnish and can impart a high adhesive force during heating.

  Among the above fillers, silica filler is preferably used from the viewpoint of dispersibility in solvents, compatibility with other resin components, and high-temperature adhesiveness, and is treated with a silane coupling agent in an epoxy system, an acrylate system, or a phenyl system. Silica filler is most preferably used.

  The filler preferably has an average particle size of 10 μm or less, a maximum particle size of 25 μm or less, an average particle size of 5 μm or less, and a maximum particle size of 20 μm or less. When the average particle diameter exceeds 10 μm and the maximum particle diameter exceeds 25 μm, the effect of improving fracture toughness tends to be not obtained. Although there is no restriction | limiting in particular in a lower limit, Usually, both are 0.01 micrometer.

  The filler preferably satisfies both an average particle size of 10 μm or less and a maximum particle size of 25 μm or less. When a filler having a maximum particle size of 25 μm or less but an average particle size exceeding 10 μm is used, there is a tendency that high adhesive strength cannot be obtained. Further, when a filler having an average particle size of 10 μm or less but having a maximum particle size exceeding 25 μm is used, the particle size distribution is widened and the adhesive strength tends to vary. Moreover, in this embodiment, when processing and using an adhesive composition in the shape of a thin film, there exists a tendency for the surface to become rough and for adhesive force to fall.

  Examples of the method for measuring the average particle size and the maximum particle size of the filler include a method of measuring the particle size of about 200 fillers using a scanning electron microscope (SEM). As a measuring method using SEM, for example, a sample obtained by adhering a semiconductor element and a semiconductor mounting support member using an adhesive layer and then heat-curing (preferably at 150 to 200 ° C. for 1 to 10 hours) is used. The method of producing, cutting the center part of this sample, and observing the cross section by SEM etc. is mentioned. At this time, it is preferable that the existence probability of the filler is 80% or more of the total filler.

  Although the usage-amount of the said filler is decided according to the characteristic or function to provide, it is 1-50 volume% with respect to the sum total of a resin component and a filler, Preferably it is 2-40 volume%, More preferably, it is 5-30 volume. %. By increasing the amount of filler, a high elastic modulus can be achieved, and dicing performance (cutability by a dicer blade), wire bonding performance (ultrasonic efficiency), and adhesive strength during heating can be effectively improved. When the filler is increased more than necessary, the low-temperature sticking property and the interfacial adhesion with the adherend, which are the features of this embodiment, are impaired, and the reliability including reflow resistance is reduced. It is preferable to be within the above range. The optimal filler content is determined to balance the required properties. Mixing and kneading in the case of using a filler can be performed by appropriately combining dispersers such as a normal stirrer, a raking machine, a three-roller, and a ball mill.

  Various coupling agents can also be added to the adhesive composition of this embodiment in order to improve the interfacial bonding between different materials. Examples of the coupling agent include silane-based, titanium-based, and aluminum-based, and among them, a silane-based coupling agent is preferable because it is highly effective. The amount of the coupling agent used is preferably 0.01 to 20 parts by weight with respect to 100 parts by weight of the thermoplastic resin (A) from the viewpoints of the effect, heat resistance and cost.

  In the adhesive composition of the present embodiment, an ion scavenger can be further added in order to adsorb ionic impurities and improve insulation reliability during moisture absorption. Such an ion scavenger is not particularly limited, for example, triazine thiol compound, a compound known as a copper damage inhibitor to prevent copper from being ionized and dissolved, such as a bisphenol-based reducing agent, zirconium-based, Examples include inorganic ion adsorbents such as antimony bismuth-based magnesium aluminum compounds. The amount of the ion scavenger used is preferably 0.01 to 10 parts by weight with respect to the polymer parts by weight from the viewpoint of the effect of addition, heat resistance, cost, and the like.

  In the present embodiment, a softening agent, an anti-aging agent, a colorant, a flame retardant, a tackifier such as a terpene resin, and a thermoplastic polymer component may be appropriately added to the adhesive layer. Thermoplastic polymer components used to improve adhesion and provide stress relaxation during curing include polyvinyl butyral resin, polyvinyl formal resin, polyester resin, polyamide resin, polyimide resin, xylene resin, phenoxy resin, polyurethane resin , Urea resin, acrylic rubber and the like. These polymer components preferably have a molecular weight of 5,000 to 500,000.

(Method for producing adhesive sheet)
<Step 1>
(A) Thermoplastic resin, (B) Thermosetting resin, and if necessary, other components are mixed and kneaded in an organic solvent to prepare a varnish (varnish for coating an adhesive layer), and then 25 ° C. The adhesive layer (a) with a protective film can be obtained by forming the varnish layer on a protective film having a storage elastic modulus of 1 GPa or more and drying by heating. The above mixing and kneading can be carried out by appropriately combining dispersers such as ordinary stirrers, crackers, three rolls, and ball mills. The heating and drying conditions are not particularly limited as long as the solvent used is sufficiently volatilized, but the heating is usually performed at 50 to 200 ° C. for 0.1 to 90 minutes.

<Process 2>
An adhesive sheet is obtained by laminating a base material (b) having a storage elastic modulus of 10 to 1000 MPa at 25 ° C. on the adhesive layer (a) side of the adhesive layer with protective film (a). be able to. The above laminating conditions are not particularly limited as long as laminating can be performed with no gap, but is usually performed at a roll temperature of 30 to 100 ° C. and a pressure of 0.1 to 1 MPa.

<Step 3>
The adhesive layer (a) and the base material (b) of the adhesive sheet composed of the protective film, the adhesive layer (a), and the base material (b) are cut from the base material (b) side. The adhesive sheet processed into a circle can be obtained by peeling off from the protective film. By processing in this way, it is not necessary to cut the adhesive sheet when laminating to a semiconductor wafer, so that an adhesive sheet excellent in workability can be obtained. Usually, the said adhesive sheet is used by winding in roll shape around a winding core.

(Method for manufacturing semiconductor device)
<Step 1>
The base material (b) and the adhesive layer (a) of the adhesive sheet are peeled off from the protective film, and the base material (b) and the adhesive layer (a) are laminated on the semiconductor wafer and the wafer ring. . The protective film is wound into a roll around another winding core. The lamination condition of the adhesive layer (a) to the semiconductor wafer is not particularly limited as long as it can be laminated without a gap, but is usually performed at 40 to 80 ° C. and a pressure of 0.1 to 1 MPa. Moreover, the lamination conditions to the wafer ring of the adhesive layer (a) are not particularly limited, but are usually 20 to 40 ° C. and a pressure of 0.1 to 1 MPa. At this time, a diced semiconductor chip can be laminated instead of the semiconductor wafer.

<Process 2>
By dicing the semiconductor wafer with the base material (b) and the adhesive layer (a) fixed to the wafer ring, an individualized semiconductor wafer is obtained. The dicing conditions are not particularly limited, but usually, the semiconductor wafer with the adhesive layer (a) and a part of the substrate (b) are diced from the semiconductor wafer side.

<Step 3>
The separated semiconductor wafer is picked up from the base material (b) to obtain a separated semiconductor chip with the adhesive layer (a). The pickup conditions are not particularly limited, but usually good pickup properties can be obtained by expanding (stretching) the substrate (b).

<Step 4>
The semiconductor chip with the adhesive layer (a) is pressure-bonded to a semiconductor element or a semiconductor mounting support member. The pressure bonding conditions are not particularly limited, but are usually performed at a temperature of 40 to 150 ° C., a load of 0.01 to 20 kgf, and a heating time of 0.1 to 5 seconds.

<Step 5>
The substrate (b) and the adhesive layer (a) are peeled off from the wafer ring.

  The adhesive sheet according to the present embodiment includes a semiconductor element such as an IC or LSI, a lead frame such as a 42 alloy lead frame or a copper lead frame; a plastic film such as a polyimide resin or an epoxy resin; It can be used as an adhesive material for die bonding for adhering to an adherend such as a semiconductor mounting support member such as ceramic such as alumina, impregnated and cured with plastic such as epoxy resin. Among them, it is suitably used as an adhesive material for die bonding for bonding an organic substrate having an uneven surface on a surface such as an organic substrate having an organic resist layer on the surface and an organic substrate having wiring on the surface, and a semiconductor element.

  Further, in the Stacked-PKG having a structure in which a plurality of semiconductor elements are stacked, it is also suitably used as an adhesive material for bonding the semiconductor elements to the semiconductor elements.

(Semiconductor device)
A semiconductor device provided with the adhesive sheet of this embodiment will be described. In recent years, semiconductor devices having various structures have been proposed, and the use of the adhesive sheet of the present embodiment is not limited to the semiconductor devices having the structure described below.

  In one form of the semiconductor device, the semiconductor element is bonded to the semiconductor mounting support member via the semiconductor adhesive sheet of the present embodiment, and the connection terminal of the semiconductor element is electrically connected to the external connection terminal via the wire. And is sealed with a sealing material.

  In another form of the semiconductor device, the first-stage semiconductor element is bonded to the semiconductor mounting support member via the semiconductor adhesive sheet of this embodiment, and the semiconductor of this embodiment is further formed on the first-stage semiconductor element. The second-stage semiconductor element is bonded through the adhesive sheet for use. The connection terminals of the first-stage semiconductor element and the second-stage semiconductor element are electrically connected to external connection terminals via wires and sealed with a sealing material. Thus, the semiconductor adhesive sheet of this embodiment can be suitably used for a semiconductor device having a structure in which a plurality of semiconductor elements are stacked.

  In addition, a semiconductor device (semiconductor package) having the above-described structure sandwiches the semiconductor adhesive sheet of this embodiment between a semiconductor element and a semiconductor mounting support member, and bonds them by thermocompression bonding. It can be obtained through a wire bonding step and, if necessary, a step such as a sealing step with a sealing material.

<(A) Thermoplastic resin>
(PI-1)
A diamine, 2-bis [4- (4-aminophenoxy) phenyl] propane (trade name “BAPP”, molecular weight 410) is placed in a 500 mL flask equipped with a stirrer, a thermometer, and a nitrogen displacement device (nitrogen inflow pipe). , 12.3 g (0.03 mol) of Wakayama Seika Kogyo Co., Ltd., 26.0 g (0.06 mol) of polyoxypropylenediamine (trade name “D-400” (molecular weight: 433), manufactured by BASF), And 8.6 g (0.01 mol) of amino-modified silicone oil (trade name “KF-8010”, molecular weight 860, manufactured by Shin-Etsu Silicone) and 250 g of NMP (N-methyl-2-pyrrolidone) as a solvent, The diamine was dissolved in the solvent by stirring.

  To the flask, 53.2 g (0.102 mol) of decamethylene bistrimellitate dianhydride (hereinafter “DBTA”, molecular weight 522) was added to the solution in the flask. After stirring for 1 hour, a reflux condenser with a moisture receiver was attached to the flask, and the solution was heated to 180 ° C. and kept for 5 hours to obtain a polyimide resin (PI-1). When GPC measurement (Gel Permeation Chromatography) was performed, Mw was 70000 in terms of polystyrene, and Tg of (PI-1) was 45 ° C. (PI-1) This corresponds to the resin represented by the formula (A).

(PI-2)
In a 500 mL flask equipped with a stirrer, a thermometer, and a nitrogen displacement device (nitrogen inlet pipe), 12.3 g (0.03 mol) of BAPP and 26.0 g (0.06 mol) of D-400 are diamines. 1,1,3,3-tetramethyl-1,3-bis (3-aminopropyl) disiloxane (trade name “BY16-871EG”, manufactured by Toray Dow Corning Co., Ltd.) 2.485 g (0.01 mol) ) And 250 g of NMP as a solvent were added and stirred to dissolve the diamine in the solvent.

  To the flask, DBTA was added to the solution in the 53.2 g (0.102 mol) flask. After completion of the addition, the mixture was stirred at room temperature for 1 hour while blowing nitrogen gas. Thereafter, a reflux condenser with a moisture acceptor was attached to the flask, and the solution was heated to 180 ° C. and kept for 5 hours to obtain a polyimide resin (PI-2). When GPC measurement of (PI-2) was performed, it was Mw = 70000 in terms of polystyrene. Moreover, Tg of (PI-2) was 45 degreeC.

(PI-3)
In a 500 mL flask equipped with a stirrer, a thermometer, and a nitrogen displacement device (nitrogen inflow tube), 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (trade name “BIS-”), which is a diamine, was added. AP-AF ”(molecular weight: 366, manufactured by Central Glass Co., Ltd.) 10.98 g (0.03 mol), D-400 26.0 g (0.06 mol), amino-modified silicone oil (trade name“ KF-8010 ”, 8.6 g (0.01 mol) of molecular weight 860, manufactured by Shin-Etsu Silicone) and 250 g of NMP as a solvent were charged and stirred to dissolve the diamine in the solvent.

  To the flask, DBTA was added to the solution in the 53.2 g (0.102 mol) flask. After completion of the addition, the mixture was stirred at room temperature for 1 hour while blowing nitrogen gas. Thereafter, a reflux condenser with a moisture acceptor was attached to the flask, and the solution was heated to 180 ° C. and kept for 5 hours to obtain a polyimide resin (PI-3). When GPC measurement of (PI-3) was performed, it was Mw = 70000 in terms of polystyrene. Moreover, Tg of (PI-3) was 50 ° C. In addition, (PI-3) corresponds to the resin represented by the general formula (A).

<Base material (b)>
The following were prepared as the substrate (b).
Substrate 1: Polyethylene (POF-120A, manufactured by Ron Seal Co., Ltd., surface irregularity (average surface roughness Ra): 100 nm, storage elastic modulus at 25 ° C .: 100 MPa, film thickness: 80 μm, no corona treatment, surface free energy: 25 mN / m, softening temperature: 100 ° C.).
Substrate 2: Polyethylene (POF-120A, manufactured by Ron Seal Co., Ltd., surface unevenness: 300 nm, storage elastic modulus at 25 ° C .: 100 MPa, film thickness: 80 μm, no corona treatment, surface free energy: 25 mN / m, softening temperature: 100 ° C).
Base material 3: Polyethylene (POF-120A, manufactured by Ron Seal, Inc., storage elastic modulus at 25 ° C .: 100 MPa, film thickness: 80 μm, with corona treatment, surface free energy: 47 mN / m, softening temperature: 100 ° C.)
Substrate 4: Hydrogenated SBR-containing polypropylene system (soft Dynasoft, manufactured by JSR Trading, storage elastic modulus at 25 ° C .: 200 MPa, film thickness: 80 μm, no corona treatment, surface free energy: 30 mN / m, softening temperature: 140 ° C.).
Base material 5: Polyester type (Dynasoft with polar group (polypropylene containing ethylene vinyl acetate copolymer), manufactured by JSR Trading Co., Ltd., storage elastic modulus at 25 ° C .: 200 MPa, film thickness: 80 μm, no corona treatment, surface free energy : 36 mN / m, softening temperature: 140 ° C.).
Substrate 6: Polyester (super soft PBT (polymer containing polybutylene terephthalate skeleton), manufactured by JSR Trading Co., Ltd., storage elastic modulus at 25 ° C .: 600 MPa, film thickness: 80 μm, no corona treatment, surface free energy: 38 mN / m , Softening temperature: 220 ° C)
Base material 7: Polypropylene (pyrene film OT P2111, manufactured by Toyobo Co., Ltd., storage elastic modulus at 25 ° C .: 2000 MPa, film thickness: 30 μm, no corona treatment).

[Storage modulus of base material (b) at 25 ° C.]
The storage elastic modulus at 25 ° C. of the base material (b) was determined by cutting the base material (b) into 5 mm width strips and using a viscoelasticity analyzer “RSA-2” (trade name) manufactured by Rheometrics. The temperature was measured under the conditions of a heating rate of 5 ° C./min, a frequency of 1 Hz, and a measurement temperature of −50 to 100 ° C.

[Average surface roughness (Ra)]
The average surface roughness (Ra) of the substrate (b) is a surface roughness measuring device “SE-2300” (trade name) manufactured by Kosaka Laboratory Ltd. It is a value of center line average roughness when measured at 5 mm / sec and an evaluation length of 1 mm.

[Surface free energy of substrate (b)]
The surface free energy of the base material (b) is obtained by using a contact angle meter (DropMaster 500, manufactured by Kyowa Interface Science Co., Ltd.) as the contact angle when water, glycerin and formamide are used as probe liquids for the base material (b). It was measured at an appropriate amount of 1 μL at a measurement temperature of 25 ° C. and determined by an acid-base method using analysis software (FAMAS, manufactured by Kyowa Interface Science Co., Ltd.) mounted on a contact angle meter.

<Adhesive composition>
Using the polyimide resins (PI-1) to (PI-3) obtained above, each component was blended in the composition ratios (unit: parts by mass) shown in Tables 1 and 2 below. Examples 1 to 9 And the adhesive composition (varnish for adhesive layer formation) of Comparative Examples 1-6 was obtained.

In Tables 1 and 2, each symbol means the following.
1032H60: manufactured by Japan Epoxy Resin Co., Ltd., tris (hydroxyphenyl) methane type epoxy resin (5% weight loss temperature: 350 ° C., solid epoxy, softening point 60 ° C.). 1032H60 is represented by the above chemical formula (I).
EXA-4710: manufactured by DIC, naphthalene type epoxy resin (5% weight loss temperature: 400 ° C., solid epoxy, softening point 95 ° C.). EXA-4710 is represented by the above chemical formula (II).
HP-7200 :: dicyclopentadiene type epoxy resin manufactured by DIC (5% weight loss temperature: 300 ° C., solid epoxy, softening point 60 ° C.).
YDF-8170C: manufactured by Tohto Kasei Co., Ltd., bisphenol F type bisglycidyl ether (5% weight loss temperature: 270 ° C., liquid epoxy).
2PHZ-PW: manufactured by Shikoku Kasei Co., Ltd., 2-phenyl-4,5-dihydroxymethylimidazole (average particle size: about 3 μm).
NMP: N-methyl-2-pyrrolidone manufactured by Kanto Chemical Co., Inc.

<Adhesive sheet>
By the method shown below, the adhesive sheet for semiconductors of each Example and comparative example which have the structure shown to Table 1, 2 was produced. First, each of the obtained adhesive compositions was dried using an applicator (YBA-5 type, manufactured by Yoshimitsu Seiki Co., Ltd.) so that it would be 10 μm after drying, respectively, with a PET film with a release treatment agent (A31, manufactured by Teijin DuPont Film). , 50 μm thickness), and heated in an oven at 80 ° C. for 20 minutes, followed by heating at 120 ° C. for 20 minutes to form an adhesive layer. The obtained pressure-sensitive adhesive sheet with PET film is pressed against a predetermined substrate (b) with a roll at a predetermined temperature with the adhesive layer facing the substrate (b) (linear pressure 4 kgf / cm And a PET film was peeled and removed to obtain an adhesive sheet comprising an adhesive layer (a) and a substrate (b).

<Evaluation test>
[Peel peeling strength (Y) between adhesive layer (a) and substrate (b)]
The adhesive sheet composed of the adhesive layer (a) and the base material (b) produced by the above method is cut into a strip shape having a width of 1 cm and a length of 4 cm. On the other hand, at a temperature of 50 ° C., a sample was prepared by pressing the adhesive layer with a roll (linear pressure 4 kgf / cm, feed rate 0.5 m / min) with the adhesive layer facing the silicon wafer. The base material (b) of the obtained sample was partially peeled from the adhesive layer (a) and the base material (b) portion was fixed with a jig, and the 90-degree tensile strength against the adhesive layer was measured. The maximum value obtained in this manner was defined as peel peel strength (Y). As a measuring device, Strograph ES (peeling speed 50 mm / min, 25 ° C.) manufactured by Toyo Seiki Seisakusho Co., Ltd. was used. The results are shown in Tables 1 and 2. In the table, “adhesiveness between substrate (b) / adhesive layer (a)” is synonymous with peel peel strength (Y).

[Surface free energy of adhesive layer (a)]
With respect to the adhesive layer surface on the opposite side of the base material (b) of the adhesive sheet comprising the adhesive layer (a) and the base material (b) produced by the above method, water, glycerin and formamide Using the contact angle meter (DropMaster 500, manufactured by Kyowa Interface Science Co., Ltd.) as the probe liquid, the contact angle is measured at an appropriate amount of 1 μL and the measurement temperature is 25 ° C., and the analysis software (FAMAS installed in the contact angle meter is used. , Manufactured by Kyowa Interface Science Co., Ltd.). The results are shown in Tables 1 and 2. The “surface energy” in the table is synonymous with surface free energy.

[SUS adhesion]
SUS304 plate (thickness: 500 μm), the above adhesive sheet prepared in a strip shape with a width of 1 cm and a length of 4 cm was pressed with a roll at a temperature of 25 ° C. with the adhesive layer at the SUS side (linear pressure 4 kgf / Cm, feed rate 0.5 m / min), a sample in which a 2 cm length portion of the adhesive sheet was fixed to SUS was produced. The maximum value of the values obtained by measuring the 90-degree tensile strength against SUS by fixing the adhesive sheet portion not attached to SUS of the obtained sample with a jig was taken as the adhesion strength. As a measuring device, Strograph ES (peeling speed 500 mm / min, 25 ° C.) manufactured by Toyo Seiki Seisakusho Co., Ltd. was used. The results are shown in Tables 1 and 2.

[SUS peelability]
In the above “SUS adhesion” measurement sample, the adhesive sheet portion not attached to the SUS was fixed with a jig and peeled off from the SUS at 90 ° C., and the adhesive layer did not remain on the SUS. A and the adhesive layer remaining in SUS were designated as C. As a measuring device, Strograph ES (peeling speed 1000 mm / min, 25 ° C.) manufactured by Toyo Seiki Seisakusho Co., Ltd. was used. The results are shown in Tables 1 and 2.

[Dicing, Pickup]
The adhesive sheet comprising the adhesive layer (a) and the base material (b) produced by the above method was applied to a 100-μm thick 6-inch silicon wafer heated to 50 ° C. and a wafer ring at 25 ° C. The sample was affixed by roll pressurization (linear pressure 4 kgf / cm, feed rate 0.5 m / min), and a silicon wafer and a wafer ring were fixed by the adhesive layer (a). Next, after fixing to a dicing machine and forming a chip by dicing a silicon wafer to 5 mm × 5 mm at a speed of 100 mm / sec, the chip is picked up by the pick-up machine, and chip fly and pick-up property at the time of dicing are evaluated. did. The results are shown in Tables 1 and 2. In the table, “chip skipping at the time of dicing” is the probability (% / 100 chips) of chip jumping at the time of dicing. “Pickup property” in the table is a probability (% / 100 chips) that a chip after dicing can be picked up by a pick-up die bonder.

[Melt viscosity at 120 ° C. of adhesive layer]
A melt viscosity at 120 ° C. of a sample of 100 μm thickness produced by laminating a plurality of 10 μm adhesive layers and roll pressing at 50 ° C. (linear pressure 4 kgf / cm, feed rate 0.5 m / min) Was measured using a viscoelasticity measuring device ARES (manufactured by Rheometrics Scientific F.E.). The measurement plate is a parallel plate having a diameter of 20 mm, the measurement conditions are a temperature increase of 5 ° C./min, the measurement temperature is −50 ° C. to 200 ° C., and the frequency is 1 Hz. The results are shown in Tables 1 and 2.

[Storage modulus at 180 ° C. after thermosetting of the adhesive layer]
A plurality of 10 μm adhesive layers were laminated and roll-pressed at 50 ° C. (linear pressure 4 kgf / cm, feed rate 0.5 m / min) to prepare a 100 μm thick sample on a Teflon sheet, 150 C. for 1 hour at 180.degree. C. and then for 1 hour at 180.degree. The obtained sample was cut into a strip having a width of 5 mm, and using a viscoelasticity analyzer “RSA-2” (trade name) manufactured by Rheometrix Co., Ltd., the temperature rising rate was 5 ° C./min, the frequency was 1 Hz, and the measurement temperature was −50 to The storage elastic modulus at 180 ° C. of the sample was measured under the condition of 200 ° C. The results are shown in Tables 1 and 2.

[260 ° C adhesive strength]
The adhesive sheet comprising the adhesive layer (a) and the substrate (b) prepared by the above method was laminated on the back surface of the silicon wafer by roll pressing at 50 ° C. The obtained sample was separated into pieces having a size of 3 mm × 3 mm. The silicon chip with the adhesive layer (a) separated into pieces is picked up from the base material (b) and laminated on the mirror surface side of the pre-diced silicon chip (10 mm × 10 mm × 0.40 mm), while pressing with 100 gf Pressure bonding was performed at 120 ° C. for 1 second. In this way, a sample of a laminate composed of silicon chip / adhesive layer / silicon chip and laminated in this order was obtained.

  The obtained sample was heated in an oven at 150 ° C. for 1 hour, then at 180 ° C. for 1 hour, and further heated on a hot plate at 260 ° C. for 10 seconds, and then the shear adhesion tester “Dage- 4000 ”(trade name) was used to measure the adhesive strength between silicon wafers (260 ° C. adhesive strength). The measurement results are shown in Tables 1 and 2.

b ... substrate, a ... adhesive layer, 100 ... semiconductor adhesive sheet.

Claims (13)

A substrate having a storage elastic modulus at 25 ° C. of 50 to 1000 MPa,
Containing at least a thermoplastic resin and a thermosetting resin, having a thickness of 40 μm or less, and an adhesive layer laminated on the base material,
The peel strength between the adhesive layer and the substrate is 30 to 200 mN / cm,
Adhesive sheet for semiconductors. The surface free energy of the surface in contact with the adhesive layer of the substrate is 25 to 45 mN / m,
The adhesive sheet for semiconductors according to claim 1. The substrate contains at least a polymer having an ester skeleton,
The adhesive sheet for semiconductors according to claim 1 or 2. The base material contains at least a polymer having a polybutylene terephthalate skeleton,
The adhesive sheet for semiconductors according to claim 3. The substrate contains at least an ethylene vinyl acetate copolymer;
The adhesive sheet for semiconductors according to claim 3. The adhesive strength of the adhesive layer to SUS is 50 to 400 mN / cm,
The adhesive sheet for semiconductors according to any one of claims 1 to 5. The surface free energy of the adhesive layer is 15 to 30 mN / m,
The adhesive sheet for semiconductors according to claim 1. The thermoplastic resin is a polyimide resin;
The adhesive sheet for semiconductors according to any one of claims 1 to 7. The glass transition temperature of the thermoplastic resin is 80 ° C. or less,
And the melt viscosity at 120 ° C. of the adhesive layer is 20000 Pa · s or less,
The adhesive sheet for semiconductors according to any one of claims 1 to 8. The polyimide resin has a structure represented by the following general formula:
The adhesive sheet for semiconductors according to claim 8.

[Wherein, X is a tetravalent organic group, and n is an integer of 3 to 30. ]   A semiconductor wafer in which the semiconductor adhesive sheet according to claim 1 is laminated on a silicon wafer. A semiconductor element and a semiconductor mounting support member bonded using the semiconductor adhesive sheet according to any one of claims 1 to 10, and / or
A plurality of semiconductor elements bonded to each other using the semiconductor adhesive sheet,
Semiconductor device. The adhesive layer of the adhesive sheet for semiconductor according to any one of claims 1 to 10 is opposed to a semiconductor wafer and a wafer ring, and the base material and the adhesive layer are bonded to the semiconductor wafer and Laminating to the wafer ring;
Dicing the semiconductor wafer on which the base material and the adhesive layer are laminated to obtain individual semiconductor chips;
Picking up the singulated semiconductor chip from the base material to obtain the semiconductor chip with the adhesive layer;
Crimping the semiconductor chip with the adhesive layer to a semiconductor element or a semiconductor mounting support member;
Separating the substrate and the adhesive layer from the wafer ring,
A method for manufacturing a semiconductor device.

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