JP6662074B2 - Adhesive film - Google Patents

Description

  The present invention relates to an adhesive film for die bonding, which can divide an adhesive film only with an expand.

  In the process of assembling a semiconductor device such as an IC, an adhesive layer and a base film layer used in an adhesive process for fixing a wafer and the like, dicing, and overlapping a lead frame and a semiconductor chip are configured to be peelable. Various types of thermosetting semiconductor wafer dicing-die bonding adhesive films have been proposed.

  In these conventional adhesive films, dicing is performed by physical grinding. Therefore, in the case of a chip having a smaller package size in the future, defects such as chip fly during a process occur, and the yield is greatly reduced. Also, there is a problem that the chip is peeled off after the die attach because the chip becomes thin and the chip warps.

  Stealth dicing (for example, Patent Documents 1 and 2) which is applied as a process for thin wafers has been proposed, but maintenance of equipment is indispensable, and the cost is increased.

JP-A-2002-192370 JP 2003-338467 A

  With the conventional adhesive film for die bonding, dicing is performed by physical grinding, so that in the future, the package size will be reduced, causing problems such as chip skipping during the process, greatly reducing the yield. ing. Further, since the chip is thin and easily warped, the chip is peeled off after the die attach, resulting in a defect.

  The present invention provides an adhesive film that can divide a film only by expansion, can improve the yield in the thin chip manufacturing process, shorten the manufacturing tact time, and can suppress peeling after die attach.

The present invention is characterized by the following.
(1) Shear viscosity at 80 ° C. is 10,000 to 30,000 Pa · s, adhesion to silicon at 90 ° C. before curing is 1 MPa or more at 5 mm square die shear strength, and strength at break at −15 ° C. is 10 MPa. An adhesive film having the following (20 mm width film, pulling speed 500 mm / min).
(2) An adhesive film obtained by superposing a dicing tape having a stress at 100% elongation of 6 to 8 MPa in the vertical and horizontal directions and a strength at a yield point of 5 to 7 MPa in the vertical and horizontal directions on the adhesive film according to the above (1).
(3) The adhesive film according to (1), which is an epoxy group-containing (meth) acrylic copolymer, has a glass transition temperature (Tg) of −40 to 20 ° C., and has an epoxy group-containing repeating unit. The adhesive film according to the above (1) or (2), comprising an adhesive composition containing at least a high molecular weight component having a weight average molecular weight of 100,000 or more and less than 1,000,000, including 0.5 to 3.0% by mass. .
(4) The adhesive film comprises (A) a high molecular weight component, (B) a thermosetting component having a softening point of less than 30 ° C, (C) a thermosetting component having a softening point of 50 ° C or more, and (D) A) a phenolic resin having a softening point of 50 ° C. or more and 100 ° C. or less, wherein the high molecular weight component (A) is 10 to 20% by mass based on 100% by mass of the adhesive composition. (B) 5 to 15% by mass of a thermosetting component having a softening point of less than 30 ° C, (C) 5 to 15% by mass of a thermosetting component having a softening point of 50 ° C or more, and (D) softening The adhesive film according to the above (3), comprising an adhesive composition containing 10 to 25% by mass of a phenol resin having a temperature of 50 ° C or higher and 100 ° C or lower.
(5) The adhesive film according to (3) or (4), wherein the adhesive composition further contains 3 to 30% by mass of an inorganic filler having an average particle size of 0.1 to 1.0 μm.
(6) An adhesive film in which the adhesive film according to any one of (1) to (5) is a long roll.

  ADVANTAGE OF THE INVENTION The adhesive film of this invention can cut | disconnect a film only by expansion, and even if a chip | tip is thin, without producing chip peeling, it becomes possible to improve the yield in a thin chip | tip manufacturing process, and to shorten manufacturing tact. . In addition, this adhesive film is excellent in filling of wiring steps and chips, and has heat resistance and moisture resistance, so it is possible to improve the processing speed and yield of the semiconductor device while improving the reliability of the semiconductor device. Become.

  The adhesive film of the present invention is assumed to be attached to the back surface (opposite surface) of the circuit surface of a semiconductor wafer in a laminating step when manufacturing a semiconductor device.

The adhesive film of the present invention has a shear viscosity at 80 ° C. of 10,000 to 30,000 Pa · s, preferably 12,000 to 28,000 Pa · s, and more preferably 14,000 to 26,000 Pa · s. The shear viscosity can be measured using, for example, a rotary viscoelasticity measuring device.
The adhesive strength to silicon at 90 ° C. before curing is 1 MPa or more, preferably 1.5 MPa or more, more preferably 2 MPa, with a die shear strength of 5 mm square. The adhesion can be measured using, for example, a die shear measuring device.
Further, the strength at break at −15 ° C. is 10 MPa or less (20 mm width film, pulling speed 500 mm / min), preferably 5 MPa or less, more preferably 3 MPa or less. The strength at break can be measured using, for example, a high-speed tensile tester.
The stress at the time of 100% elongation of the adhesive film of the present invention is preferably 6 to 8 MPa in the vertical and horizontal directions, and more preferably 6.5 to 7.5 MPa. The strength at the yield point is preferably 5 to 7 MPa in the vertical and horizontal directions, and more preferably 5.5 to 6.5 MPa.

  The epoxy group-containing (meth) acrylic copolymer, which is a high molecular weight component used in the adhesive film of the present invention, has a glass transition temperature (Tg) of -40 to 20 ° C and has an epoxy group-containing repeating unit of 0.1 g. It is a copolymer having a weight average molecular weight of 100,000 or more and less than 1,000,000, containing 5 to 3.0% by mass.

As the epoxy group-containing (meth) acrylic copolymer, a (meth) acrylic ester copolymer, an acrylic rubber or the like can be used, and an acrylic rubber is more preferable. Acrylic rubber is a rubber having an acrylic ester as a main component and mainly composed of a copolymer such as butyl acrylate and acrylonitrile or a copolymer such as ethyl acrylate and acrylonitrile.
The (meth) acrylic copolymer means an acrylic copolymer or a methacrylic copolymer (the same applies hereinafter).

  As the functional monomer of the (meth) acrylic copolymer, one that is incompatible with the epoxy resin, the epoxy resin and the (meth) acrylic copolymer separate after curing, and the reflow crack resistance and heat resistance are reduced. This is preferable in that an adhesive that has been effectively developed can be obtained. Among them, it is preferable to use glycidyl acrylate or glycidyl methacrylate which is incompatible with the epoxy resin. The amount of the epoxy group-containing repeating unit needs to be 0.5 to 3.5% by mass in the epoxy group-containing (meth) acrylic copolymer. Within this range, it is possible to simultaneously secure the adhesive strength and prevent gelation.

  In addition to the epoxy group-containing repeating units in the (meth) acrylic copolymer, ethyl or butyl (meth) acrylic repeating units or a mixture of both can be used. The mixing ratio is determined in consideration of the glass transition temperature (hereinafter, referred to as “Tg”) of the copolymer of the present invention at −40 to 20 ° C.

The epoxy group-containing (meth) acrylic copolymer containing 0.5 to 3.5% by mass of the epoxy group-containing repeating unit is, for example, HTR-860P- manufactured by Nagase ChemteX Corporation containing 3% by mass of glycidyl. 3 can be prepared.
The polymerization method is not particularly limited, and pearl polymerization, solution polymerization and the like can be used. Thereby, the tackiness of the adhesive film in the B-stage state is appropriate, and the handleability is good.

  The weight average molecular weight of the epoxy group-containing acrylic copolymer is 100,000 to 1,000,000, preferably 500,000 to 1,000,000. When the weight average molecular weight is in this range, the strength, flexibility, and tackiness of the film or sheet can be appropriately controlled, and the flowability is good and the circuit filling property of the wiring is kept good. Can be.

  The adhesive film of the present invention comprises (A) a high molecular weight component, (B) a thermosetting component having a softening point of less than 30 ° C, (C) a thermosetting component having a softening point of 50 ° C or more, and (D) A phenolic resin having a softening point of 50 ° C. or more and 100 ° C. or less, wherein the high molecular weight component (A) is 10 to 20% by mass based on 100% by mass of the adhesive composition; (B) 5 to 15% by mass of a thermosetting component having a softening point of less than 30 ° C, (C) 5 to 15% by mass of a thermosetting component having a softening point of 50 ° C or more, and (D) a softening point Consists of an adhesive composition containing 10 to 25% by mass of a phenol resin having a temperature of 50 ° C or higher and 100 ° C or lower.

The thermosetting components (B) and (C) used in the present invention are a thermosetting resin and a curing agent thereof. For example, as the thermosetting resin, an epoxy resin, a cyanate resin, and a component other than the component (D) are used. A phenol resin is used, and an epoxy resin is preferable because of its high heat resistance.
The thermosetting component whose component (B) has a softening point of less than 30 ° C. is a thermosetting resin that is a liquid at a softening point of less than 30 ° C. or at room temperature (25 ° C.) and has an adhesive action when cured. It is not particularly limited, and examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, novolak phenol type epoxy resin, naphthalene type epoxy resin, and the like. Two or more can be used in combination. In particular, it is preferable to use a bisphenol A type epoxy resin or a bisphenol F type epoxy resin from the viewpoint of the tackiness and flexibility of the film.

The thermosetting component having a softening point of component (C) of 50 ° C. or higher includes dicyclopentadiene type epoxy resin, novolak phenol type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin and the like. The species can be used alone or in combination of two or more. In particular, it is preferable to use an epoxy resin having excellent fluidity when softened. In addition, generally known ones such as a polyfunctional epoxy resin, a glycidylamine type epoxy resin, a heterocyclic epoxy resin, and an alicyclic epoxy resin can be used.
The epoxy resin is not particularly limited as long as it has an adhesive action upon curing. For example, a bifunctional epoxy resin such as bisphenol A epoxy, a phenol novolak epoxy resin, a novolak epoxy resin such as a cresol novolak epoxy resin Etc. can be used.

  The phenolic resin having a softening point of component (D) of 50 ° C. or more and 100 ° C. or less used in the present invention is compatible with the thermosetting components of components (B) and (C) and has a softening point of 50-100 ° C. It is not particularly limited as long as it is present, and examples thereof include resole-type phenol resins such as alkylphenol resins, p-phenylphenol resins, and bisphenol-A-type phenol resins, and novolak-type phenol resins. These can be used in combination. In particular, it is preferable to use a resol type phenol resin that functions as an epoxy resin curing agent. In addition, when the softening point of the solid phenolic resin is 50 ° C. or higher and 100 ° C. or lower, compatibility with the epoxy resin is improved, and since the softening is quickly performed at the time of application, excellent adhesive properties are obtained. Can be.

  When the thermosetting component (B) or (C) is an epoxy resin, the compounding amount of the component (D) with the phenolic resin is determined from the viewpoint of curability when used as an adhesive. The equivalent ratio of the equivalents is preferably 0.70 / 0.30 to 0.30 / 0.70, more preferably 0.65 / 0.35 to 0.35 / 0.65, and further preferably 0.60 / 0.40 to 0.40 / 0.60, particularly preferably 0.55 / 0.45 to 0.45 / 0.55.

In the present invention, based on 100% by mass of the adhesive composition, 10 to 20% by mass of the (A) high molecular weight component and 5 to 15% by mass of the (B) thermosetting component having a softening point of less than 30 ° C. And (C) 5 to 15% by mass of a thermosetting component having a softening point of 50 ° C or higher, and (D) 10 to 25% by mass of a phenol resin having a softening point of 50 ° C or higher and 100 ° C or lower. I do.
When the thermosetting component (B) or (C) is an epoxy resin and the high molecular weight component (A) is an epoxy group-containing (meth) acrylic copolymer, the epoxy resin and the epoxy resin curing agent are used. The amount of the epoxy group-containing (meth) acrylic copolymer per 100 parts by mass of the total is preferably from 250 to 1000 parts by mass. That is, the ratio A / B of the total mass A of the epoxy resin and the epoxy resin curing agent to the mass B of the epoxy group-containing (meth) acrylic copolymer is preferably 0.1 to 0.4. Within this range, the effect of suppressing the flow property during molding, the handleability at high temperatures, and the embedding of unevenness of the wiring board are good.

  Moreover, it is preferable to further use an inorganic filler in the adhesive composition used in the present invention. The inorganic filler is not particularly limited, and aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisker, boron nitride , Crystalline silica, amorphous silica, etc., and these can be used alone or in combination of two or more. In order to improve thermal conductivity, it is preferable that aluminum oxide, aluminum nitride, boron nitride, crystalline silica, amorphous silica, and the like are contained. For the purpose of adjusting the melt viscosity and imparting thixotropic properties, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, crystalline silica, It is preferable to contain amorphous silica or the like.

  The use amount of the inorganic filler is preferably from 3 to 30% by mass based on the adhesive composition. Within this range, all of the storage elasticity, adhesiveness, and electrical properties due to remaining voids of the adhesive film can be secured. The average particle size of the inorganic filler is preferably from 0.1 to 1.0 μm from the viewpoint of fluidity.

  Further, a curing accelerator can be added to the adhesive composition used in the present invention. The curing accelerator is not particularly limited, and various imidazoles can be used. Examples of the imidazoles include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, and the like. They can be used together.

  The addition amount of the curing accelerator is preferably from 0.04 to 5 parts by mass, more preferably from 0.04 to 0.2 parts by mass, based on 100 parts by mass in total of the epoxy resin and the phenol resin as a curing agent. Within this range, both curability and reliability can be achieved.

  The adhesive composition constituting the adhesive film further contains various additives such as a catalyst, an additive, and a coupling agent, if necessary, in addition to the components (A) to (D) and the curing accelerator. But it is good. Although there is no particular limitation, it is preferable to include a coupling agent in order to improve the adhesive strength to the adherend.

  The adhesive film of the present invention can be obtained by dissolving or dispersing the adhesive composition used in the present invention in a solvent to form a varnish, coating the support on a support, heating and removing the solvent to form a film. it can.

  As the support, a plastic film such as polytetrafluoroethylene, polyethylene terephthalate, polyethylene, polypropylene, polymethylpentene, or polyimide can be used.These supports may be used after releasing the surface of the support. it can. Further, the support can be peeled off at the time of use to use only the adhesive film, and then used. Further, the support can be used together with the support as a support with an adhesive film, and the support can be removed later.

  The solvent for varnishing the adhesive composition is not particularly limited, but in consideration of volatility at the time of film production, methanol, ethanol, 2-methoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, It is preferable to use a solvent having a relatively low boiling point, such as methyl isobutyl ketone, 2-ethoxyethanol, toluene and xylene. In addition, a solvent having a relatively high boiling point, such as dimethylacetamide, dimethylformamide, N-methylpyrrolidone, or cyclohexanone, can be added to improve the coating properties.

  In the production of a varnish when an inorganic filler is added to the adhesive composition used in the present invention, in consideration of the dispersibility of the inorganic filler, it is preferable to use a grinder, a three-roll, ball mill, or a bead mill. , Can be used in combination. In addition, it is also possible to shorten the mixing time by mixing the inorganic filler and the low molecular weight material in advance and then blending the high molecular weight material. After the varnish is formed, bubbles in the varnish can be removed by vacuum degassing or the like.

  As a method for applying the varnish to the support, a known method can be used, and examples thereof include a knife coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, and a curtain coating method.

  The thickness of the adhesive film is not particularly limited, but is preferably 90 to 135 μm. In this range, the unevenness of the wiring board and the chip embedding property can be sufficiently exhibited, and it is economical.

  Further, in the adhesive film of the present invention, two or more sheets can be laminated to obtain a desired thickness. In this case, a bonding condition for preventing peeling of the adhesive films from each other is required.

  The adhesive film of the present invention may be used as it is, but can also be used as a dicing tape integrated adhesive film obtained by laminating the adhesive film of the present invention on a conventionally known dicing tape. As a method of laminating the adhesive film on the dicing tape, in addition to printing, a method of pressing a previously prepared adhesive film on the dicing tape and a hot roll laminating method may be mentioned. A roll lamination method is preferred. The thickness of the dicing tape is not particularly limited, and is appropriately determined depending on the thickness of the adhesive film and the use of the dicing tape-integrated adhesive film, based on the knowledge of those skilled in the art. The thickness is 60 to 200 μm, and preferably 70 to 170 μm, in terms of good handling of the film.

  Examples of the dicing tape used with the adhesive film of the present invention include plastic films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. Further, if necessary, surface treatment such as primer application, UV treatment, corona discharge treatment, polishing treatment, etching treatment and the like may be performed. The dicing tape preferably has an adhesive property, and the above-mentioned plastic film may be used by imparting adhesiveness, or an adhesive layer may be provided on one side of the above-mentioned plastic film. This is because the resin composition for the pressure-sensitive adhesive layer has an appropriate tack strength obtained by adjusting the ratio of the liquid component and the Tg of the high molecular weight component in the resin composition for the pressure-sensitive adhesive layer as generally performed. An object can be formed by applying and drying the above-mentioned plastic film.

  When the adhesive film of the present invention is used when manufacturing a semiconductor device as a dicing / die-bonding integrated adhesive film, the semiconductor element has an adhesive force such that the semiconductor element does not scatter when expanded and separated, and then can be peeled off from the dicing tape during pickup. is necessary. For example, if the adhesiveness of the adhesive film is too high, pickup may be difficult. Therefore, it is preferable to appropriately adjust the tack strength of the adhesive film. As the method, by increasing the shear viscosity at room temperature (25 ° C.) of the adhesive film, the adhesive strength and tack strength also increase, and if the melt viscosity is decreased, the adhesive strength and tack strength tend to decrease. You can use. For example, when the shear viscosity is increased, for example, a method of including a plasticizer or a method of including a tackifier may be used. Conversely, when decreasing the melt viscosity, the content of the compound may be reduced. Examples of the plasticizer include so-called diluents such as monofunctional acrylic monomers, monofunctional epoxy resins, liquid epoxy resins, and acrylic resins.

  As a method of laminating the adhesive film of the present invention on the dicing tape described above, in addition to printing, a method of laminating by laminating a previously prepared adhesive film on a dicing tape by pressing and hot roll laminating, A method using a hot roll laminate is preferable because it can be manufactured and is efficient.

The thickness of the dicing tape is not particularly limited, and is appropriately determined based on the knowledge of those skilled in the art, depending on the thickness of the adhesive film and the use of the dicing tape-integrated adhesive film. It is usually from 60 to 150 μm, preferably from 70 to 130 μm, from the viewpoint that the film is easy to handle.
The dicing tape is preferably a dicing tape having a stress at 100% elongation in the vertical and horizontal directions of 6 to 8 MPa and a strength at the yield point of 5 to 7 MPa in the vertical and horizontal directions (20 mm width film, pulling speed of 500 mm / min). When the stress at the time of 100% elongation exceeds these ranges, there is a tendency that it cannot be divided by the expansion. Further, if the strength at the yield point has a large difference in the length and width, the material tends to be unable to be divided by the expansion.

  The wiring board for mounting a semiconductor as an adherend of the adhesive film of the present invention can be used without being limited to a substrate material such as a lead frame having a die pad, a chip of a stacked MCP, a ceramic substrate or an organic substrate. As the ceramic substrate, an alumina substrate, an aluminum nitride substrate, or the like can be used. As the organic substrate, use an FR-4 substrate in which glass cloth is impregnated with an epoxy resin, a BT substrate in which bismaleimide-triazine resin is impregnated, and a polyimide film substrate using a polyimide film as a base material. Can be.

  The shape of the wiring may be any of single-sided wiring, double-sided wiring, and multi-layered wiring, and a through-hole or a non-through-hole electrically connected may be provided as necessary. Further, when the wiring appears on the outer surface of the semiconductor device, it is preferable to provide a protective resin layer.

As a method of attaching the adhesive film to the wiring board, a method of cutting the adhesive film into a predetermined shape and thermocompression bonding the cut adhesive film to a desired position on the wiring board is generally used. It does not do. When using a dicing tape-integrated adhesive film in which an adhesive film is laminated on a dicing tape, this adhesive film surface is laminated on the opposite surface of the circuit-formed wafer, and the dicing tape is used to separate the semiconductor elements with the adhesive film from the dicing tape. The method of peeling and bonding the adhesive film surface to a wiring board by thermocompression bonding is preferable.
For the curing of the adhesive film, the composition of the adhesive composition is adjusted so that the curing rate at 150 ° C. for 0.5 hour is 60% or more. The cure rate can be measured using a differential scanning calorimeter (DSC).

  As the semiconductor element, a general semiconductor element such as an IC, an LSI, and a VLSI can be used.

  The thermal stress generated between the semiconductor element and the wiring board is remarkable when the area difference between the semiconductor element and the wiring board is small. However, by using the adhesive film having a low elastic modulus of the present invention, the thermal stress is relieved by reducing the thermal stress. Ensure the nature. These effects appear very effectively when the area of the semiconductor element is 70% or more of the area of the wiring board. In a semiconductor device having a small area difference between a semiconductor element and a wiring board, external connection terminals are often provided in an area.

  Further, as a characteristic of the adhesive film of the present invention, in the step of heating the adhesive film to a desired position of the wiring substrate, such as a step of thermocompression bonding, and a step of connecting by wire bonding, volatile components from the adhesive layer are removed. Can be suppressed.

  Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto.

(Example 1)
As the epoxy resin of the thermosetting component (C), an o-cresol novolak type epoxy resin having an epoxy equivalent of 210 g / eq (trade name: YDCN-700-10, manufactured by Nippon Steel & Sumitomo Metal Corporation, softening point: 80 ° C.) ), Bisphenol F-type epoxy resin having an epoxy equivalent of 160 g / eq (EXA-830CRP, trade name, manufactured by DIC Corporation, liquid at 25 ° C.) having an epoxy equivalent of 160 g / eq as the epoxy resin of the component (B); A phenol resin (manufactured by Mitsui Chemicals, Inc., trade name: XLC-LL, softening point: 75 ° C.) as an epoxy resin curing agent, and 3-mercaptopropyltrimethoxysilane (momentive performance) as a silane coupling agent・ Materials Japan GK, product name: A-189) and 3-ureidoprop Triethoxysilane (manufactured by Momentive Performance Materials Japan GK, trade name: A-1160), as a filler, spherical silica having an average particle diameter of about 0.1 μm (trade name, manufactured by Admatechs Co., Ltd.) Cyclohexanone was added to the composition consisting of Admanano) and mixed by stirring.

An acrylic rubber containing 3.0% by mass of a glycidyl group-containing repeating unit as a component (A) (manufactured by Nagase ChemteX Corporation, trade name: HTR-860P-3, weight average molecular weight: 800,000) By mass ratio, butyl acrylate / ethyl acrylate / acrylonitrile / glycidyl methacrylate contains 38.6 / 28.7 / 29.7 / 3.0), and 1-cyanoethyl-2-phenylimidazole (Shikoku) as a curing accelerator Kasei Kogyo Co., Ltd., trade name: 2PZ-CN) was mixed and vacuum degassed. The varnish prepared in this manner was applied on a release-treated polyethylene terephthalate film having a thickness of 38 μm, and was dried by heating at 90 ° C. for 5 minutes and at 130 ° C. for 5 minutes. Was formed, and an adhesive film provided with a carrier film (support film) was produced. Hereinafter, similarly, each adhesive film of Table 1 was produced. Table 1 shows the blending mass% of Examples 1-2 and Comparative Examples 1-3.
As dicing tapes, A, B, and C having different physical properties shown in Table 1 were used.

The following properties were measured and evaluated using the adhesive film obtained above.
[Measurement of shear viscosity at 80 ° C]
The viscosity at 80 ° C. of the adhesive film (adhesive layer) before curing was measured by a shear viscosity measurement. Specifically, a measurement sample (film before curing) was prepared as follows. Coated on a 38 μm-thick polyethylene terephthalate film that has been release-treated in the same manner as above, and dried by heating at 90 ° C. for 5 minutes and at 130 ° C. for 5 minutes to obtain a B-stage film having a thickness of about 84 μm. The adhesive film was formed and provided with a support film. After peeling and removing the support film, the two adhesive layers are bonded at 60 ° C. to obtain a film having a thickness of 168 μm. Next, the film is punched in the thickness direction to obtain a disk-shaped viscosity measurement sample having a diameter of 10 mm and a thickness of 168 μm. A circular aluminum plate jig with a diameter of 8 mm is set in a rotary viscoelasticity measuring device (ARES-RDA, manufactured by TA Instruments Japan Co., Ltd.), and the support film is peeled from the punched viscosity measurement sample. Set to Thereafter, the shear viscosity was measured while increasing the temperature at a rate of 5 ° C./min from room temperature (25 ° C.). The measured value was recorded until the temperature reached 120 ° C., and the shear viscosity at 80 ° C. was measured.
The adhesive film (adhesive layer) of the present invention has a shear viscosity at 80 ° C. before curing of 10,000 to 30,000 Pa · s. If the viscosity is less than 10000 Pa · s, there is a concern that the adhesive film may protrude from the wafer during die bonding in the semiconductor device manufacturing process and contaminate the device. On the other hand, if it is larger than 30,000 Pa · s, the unevenness at the time of pressure bonding tends to deteriorate.

(Measurement of strength at break)
The strength at break of the adhesive film (adhesive layer) was measured by the following procedure. A strip-shaped sample for a tensile test measurement is cut out to a width of 20 mm and a length of 100 mm.
After peeling and removing the support film, the support film is set on an autograph (manufactured by Toyo Baldwin Co., Ltd., UTM-III-500, “Autograph” is a registered trademark) so that the distance between the jigs becomes 50 mm. Thereafter, the film is cooled to -15 ° C, the film length is measured while pulling at a speed of 500 mm / min, and the strength of the film when the film is broken is read.
The adhesive film (adhesive layer) of the present invention has a strength at break at -15 ° C before curing of 10 MPa or less. If the strength at break exceeds 10 MPa, there is a tendency that it cannot be divided by the expansion.

[Measurement of adhesion to silicon]
The adhesion to silicon was measured as follows. First, a varnish for an adhesive film was applied to a support film to prepare an uncured adhesive film having a thickness of 10 μm, and the adhesive layer was attached to a 400 μm-thick silicon wafer at 60 ° C. Thereafter, the silicon wafer was cut into a square of 5 mm, and pressed on a silicon wafer at 120 ° C., 0.4 MPa, and 5 s so that the adhesive layer side became a silicon wafer, thereby producing a test piece.
Thereafter, a die shear measurement is performed at a stage temperature of 90 ° C.
The adhesive (adhesive layer) film of the present invention has an adhesion to a silicon wafer of 1 MPa or more at 90 ° C. before curing. If the adhesive force is less than 1 MPa, the chip tends to peel off after die attach because the chip warps in a thin chip. The adjustment of the adhesive force can be adjusted, for example, by increasing or decreasing the blending amount of the inorganic filler.

[Measurement of stress at 100% elongation and yield point (hour) strength]
The tensile properties of the adhesive films A, B and C as dicing films were measured according to the following procedure. A strip-shaped measurement sample is obtained by cutting out a length of 20 mm and a length of 100 mm in the vertical and horizontal directions.
The measurement sample is set on an autograph (manufactured by Toyo Baldwin Co., Ltd., UTM-III-500, “Autograph” is a registered trademark) so that the distance between the jigs is 50 mm. Thereafter, the film length and stress are measured at room temperature (25 ° C.) while pulling at a speed of 500 mm / min until the film breaks.
Then, the stress at 100% elongation and the strength at the yield point were determined.
The pressure-sensitive adhesive film used in the present invention has a stress at 100% elongation of 6 to 8 MPa in the vertical and horizontal directions and a strength at a yield point of 5 to 7 MPa in the vertical and horizontal directions. When the stress at the time of 100% elongation exceeds these ranges, there is a tendency that it cannot be divided by the expansion. Further, if the strength at the yield point has a large difference in the length and width, the material tends to be unable to be divided by the expansion.

[Evaluation of chip peeling]
A semiconductor chip with an adhesive film (length 10 mm, width 10 mm, thickness 30 μm) is pressure-bonded to a substrate with a chip (length 10 mm, width 10 mm, thickness 50 μm) at 120 ° C., 40 N for 1 second to produce a sample, and the chip is peeled off. Was observed. The cross section was observed and the substrate was visually observed from the back surface, and evaluation was made as “「 ”when there was no peeling, and as“ X ”when there was no peeling.

(Dividability evaluation)
A silicon wafer with an adhesive film (length 10 mm, width 10 mm, thickness 30 μm line) was cooled and expanded. Cooling temperature: 0 ° C., push-up amount: 10 mm. Then, the presence or absence of division was observed. A sample that was irradiated with light and passed through the divided sample was evaluated as “O”, and a sample that was not transmitted was evaluated as “X”.
Table 1 summarizes the above measurement and evaluation results.

From Table 1, it is found that Comparative Example 1 using an adhesive film having a silicon adhesion smaller than the specified range and a breaking strength larger than the specified range was inferior in chipping of the wafer and chipped.
Further, in Comparative Example 3 in which the shear viscosity was larger than the specified range, the cutting performance of the wafer was inferior. And, even if a combination using a film out of the specific range is used as the adhesive film (dicing tape), it is inferior in the dividing property.
On the other hand, in Examples 1 and 2 using the adhesive film within the specified range, a film having excellent breakability and performance without chip peeling could be obtained.

As described above, the present invention has been described with reference to the embodiments. When the adhesive film of the present invention is used, the wiring step is sufficient in the heating temperature range applied in the die bonding step or the curing step, the chip is excellent in filling property, and the chip does not peel off due to the influence of the substrate warpage. Becomes possible.
Further, it has heat resistance and moisture resistance necessary for mounting a semiconductor chip on a wiring board. Thus, according to the adhesive film of the present invention, it is possible to improve the processing speed and the yield of the semiconductor device as well as the reliability of the semiconductor device.

Claims (5)

(A) an epoxy group-containing (meth) acrylic copolymer having a glass transition temperature (Tg) of −40 to 20 ° C. and containing 0.5 to 3.0% by mass of an epoxy group-containing repeating unit; A high molecular weight component having a weight average molecular weight of 100,000 or more and less than 1,000,000,
(B) a thermosetting component having a softening point of less than 30 ° C.,
(C) a thermosetting component having a softening point of 50 ° C. or more;
(D) a phenol resin having a softening point of 50 ° C or higher and 100 ° C or lower;
An adhesive composition comprising: (A) 10 to 47% by mass of a high molecular weight component, and (B) a thermosetting resin having a softening point of less than 30 ° C based on 100% by mass of the adhesive composition. 5 to 15% by mass of the thermosetting component, 5 to 19% by mass of the thermosetting component (C) having a softening point of 50 ° C or more, and 10 (P) of a phenol resin having a softening point of 50 ° C or more and 100 ° C or less. Comprising the adhesive composition, containing
The adhesive composition further includes an inorganic filler in an amount of 3 to 6% by mass based on 100% by mass of the adhesive composition,
The shear viscosity at 80 ° C. is 10,000 to 30,000 Pa · s, the adhesion to silicon at 90 ° C. before curing is 1 MPa or more at a die shear strength of 5 mm square, and the strength at break at −15 ° C. is 10 MPa or less (20 mm An adhesive film having a width film and a pulling speed of 500 mm / min). (A) an epoxy group-containing (meth) acrylic copolymer having a glass transition temperature (Tg) of −40 to 20 ° C. and containing 0.5 to 3.0% by mass of an epoxy group-containing repeating unit; A high molecular weight component having a weight average molecular weight of 100,000 or more and less than 1,000,000,
(B) a thermosetting component having a softening point of less than 30 ° C.,
(C) a thermosetting component having a softening point of 50 ° C. or more;
(D) a phenol resin having a softening point of 50 ° C or higher and 100 ° C or lower;
An adhesive composition comprising: (A) 10 to 47% by mass of a high molecular weight component, and (B) a thermosetting resin having a softening point of less than 30 ° C based on 100% by mass of the adhesive composition. 5 to 15% by mass of the thermosetting component, 5 to 19% by mass of the thermosetting component (C) having a softening point of 50 ° C or more, and 10 (P) of a phenol resin having a softening point of 50 ° C or more and 100 ° C or less. Comprising the adhesive composition, containing
The adhesive composition contains no inorganic filler,
The shear viscosity at 80 ° C. is 10,000 to 30,000 Pa · s, the adhesion to silicon at 90 ° C. before curing is 1 MPa or more at a die shear strength of 5 mm square, and the strength at break at −15 ° C. is 10 MPa or less (20 mm An adhesive film having a width film and a pulling speed of 500 mm / min). The adhesive film according to claim 1, wherein the inorganic filler has an average particle size of 0.1 to 1.0 μm. At 100% elongation of the stress 6~8MPa in vertical and horizontal directions, 5～7MPa during strength in the horizontal and vertical directions yield either a dicing tape is (20 mm wide film, pulling rate of 500 mm / min) according請1-3 one An adhesive film superimposed on the adhesive film according to the item . An adhesive film in which the adhesive film according to any one of claims 1 to 4 is a long wound body.