KR102212774B1 - Film-like adhesive, dicing tape-integrated film-like adhesive, and method for manufacturing semiconductor device - Google Patents

Abstract

The present invention is a film adhesive for semiconductor devices containing a thermosetting resin, a curing agent, and conductive particles, and having a glass transition temperature of 130°C or higher after thermosetting.

Description

Film adhesive, dicing tape integrated film adhesive, and manufacturing method of semiconductor device {FILM-LIKE ADHESIVE, DICING TAPE-INTEGRATED FILM-LIKE ADHESIVE, AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE}

The present invention relates to a film adhesive, a dicing tape integrated film adhesive, and a method of manufacturing a semiconductor device.

In the manufacture of a semiconductor device, a method of bonding a semiconductor element to a metal lead frame or the like (a so-called die bonding method) started with a conventional gold-silicon process, and has been changed to a method using solder and resin paste. Currently, a method using a conductive resin paste is used.

However, in the method of using a resin paste, there is a problem that the conductivity is lowered due to voids, the thickness of the resin paste is uneven, or the pad is contaminated by protrusion of the resin paste. In order to solve these problems, a film adhesive may be used instead of a resin paste (see, for example, Patent Document 1).

Further, Patent Document 2 discloses a film adhesive in which flexibility is imparted by blending an acrylic acid copolymer having a glass transition temperature of -10 to 50°C in order to reduce thermal damage to a semiconductor device or a lead frame.

Japanese Patent Application Laid-Open No. Hei 6-145639 Japanese Patent No. 4137827

However, conventionally, an adhesive having heat resistance has been desperately desired. In particular, since power semiconductor devices that control and supply power generally have a large amount of heat, high heat resistance is required for the adhesive used in the power semiconductor device.

The inventors of the present invention carefully studied the film adhesive for semiconductor devices. As a result, when the glass transition temperature (Tg) after curing was higher than a predetermined temperature, it was found that heat resistance was excellent, and the present invention was completed.

That is, the film adhesive for semiconductor devices according to the present invention,

Including a thermosetting resin, a curing agent and conductive particles,

It is characterized in that the glass transition temperature after heat curing is 130°C or higher.

According to the above configuration, since the glass transition temperature after thermal curing is 130°C or higher, it has heat resistance. Therefore, when used in a semiconductor device, it can withstand heat generation from a semiconductor element or the like. Further, since it contains conductive particles, it becomes possible to efficiently discharge heat generated from a semiconductor element or the like to the outside.

In the above arrangement, the electrical resistivity at 25 ℃ after curing 1 × 10 ^- is preferably ² Ω · m or less. The electric resistivity is low, a high electrical conductivity, thermal conductivity because it is proportional to the conductivity, the electric resistivity at 25 ℃ after curing 1 × 10 ^- is less than ² Ω · m Thermal conductivity is relatively high. As a result, heat from a semiconductor element or the like can be efficiently radiated to the outside. In particular, when used in a compact and high-density mounted semiconductor device, heat can be properly radiated to the outside.

In the above configuration, when a thermoplastic resin is included, the weight of the thermoplastic resin is A, and the total weight of the thermosetting resin and the curing agent is B, the weight ratio (A)/(B) is 1/9 to 4 It is preferably within the range of /6. If the weight ratio (A)/(B) is 4/6 or less, the curing component becomes sufficient, and it becomes easy to increase the glass transition temperature after thermal curing. On the other hand, film formation becomes easy if the said weight ratio (A)/(B) is 1/9 or more.

In the above configuration, it is preferable that the content of the conductive particles is 30 to 95% by weight based on the entire film adhesive. When the content of the conductive particles is 30% by weight or more with respect to the entire film adhesive, it is easy to increase the thermal conductivity. As a result, heat from a semiconductor element or the like can be more efficiently radiated to the outside. On the other hand, when the content of the conductive particles is 95% by weight or less with respect to the entire film adhesive, film formation becomes easy.

In the above configuration, it is preferable that the tensile storage modulus at 175°C after heat curing is 50 to 1500 MPa. If the storage modulus at 175°C after heat curing is 50 MPa or more, the semiconductor element or the like can be firmly adhered to the adherend. On the other hand, if the storage modulus at 175°C after heat curing is 1500 MPa, it has a certain degree of flexibility, so it can withstand thermal stress, and peeling from the adherend can be suppressed.

In the above configuration, it is preferable that the shear adhesion to copper at 150° C. after maintaining at 0.5 MPa for 0.5 seconds at 150° C. is in the range of 5 to 200 g/25 mm 2. Since the shear adhesion is 5 g/25 mm 2 or more, when bonding a semiconductor element to a lead frame, it can be sufficiently softened at 150°C or less. As a result, it is possible to prevent oxidation of an adherend such as a lead frame and to achieve high adhesion to the adherend.

In the above configuration, it is preferable that the thickness is in the range of 5 to 100 μm. If the thickness is 5 μm or more, it is possible to prevent the occurrence of a non-adhesive portion even when warping of the chip occurs. On the other hand, when the thickness is 100 μm or less, it is possible to suppress excessive protrusion of the film adhesive due to the load during die bonding and contaminating the pad or the like.

In addition, in order to solve the above problems, the dicing tape integrated film adhesive of the present invention includes a dicing tape in which an adhesive layer is laminated on a substrate,

Having the film adhesive described above,

It characterized in that the film-type adhesive is formed on the pressure-sensitive adhesive layer.

In the above configuration, the peeling force of the film adhesive and the dicing tape is within the range of 0.01 to 3.00 N/20 mm under the conditions of a peel rate: 300 mm/min, peel temperature: 25° C., and a T-type peel tester. It is desirable. If the peeling force is 0.01N/20mm or more, scattering of chips during dicing can be suppressed. In addition, if the peeling force is 3.00N/20mm or less, pickup can be facilitated.

In addition, the method for manufacturing a semiconductor device of the present invention is a method for manufacturing a semiconductor device using the dicing tape-integrated film adhesive described above,

Step A of attaching a semiconductor wafer to the film adhesive of the dicing tape integrated film adhesive,

Step B of dicing the semiconductor wafer together with the film adhesive,

Step C of picking up a semiconductor element equipped with a film adhesive obtained by dicing, and

Step D of maintaining the film-type adhesive in the range of 0.05 to 40 MPa for 0.01 to 2 seconds in the range of 50 to 150°C after contacting the semiconductor device with the film-type adhesive to an adherend, and

It is a method for manufacturing a semiconductor device, comprising a step E of thermosetting the film adhesive after the step D.

According to the above configuration, after the semiconductor element provided with the picked up film adhesive is brought into contact with the adherend, the film adhesive is maintained within the range of 0.05 to 40 MPa for 0.01 to 2 seconds in the range of 50 to 150°C. (Step D). Therefore, when a semiconductor element is adhered to an adherend such as a lead frame, the film-type adhesive can be sufficiently softened at a temperature within the range of 50 to 150° C., so that it can be brought into close contact. Since 150°C or less softens the film-type adhesive at a relatively low temperature, oxidation of the adherend (eg, lead frame) can be prevented. Then, the film adhesive is thermally cured (Step E). This makes it possible to obtain a semiconductor device capable of withstanding heat generation. In addition, since the film adhesive contains conductive particles, it becomes possible to efficiently discharge heat generated from a semiconductor element or the like to the outside.

According to the film adhesive and dicing tape integrated film adhesive of the present invention, when used in a semiconductor device, it is possible to withstand heat generation from a semiconductor element, etc., and it becomes possible to efficiently discharge heat from a semiconductor element to the outside. .

Further, according to the method for manufacturing a semiconductor device of the present invention, it is possible to prevent oxidation of an adherend and to provide a semiconductor device capable of withstanding heat generation. In addition, it becomes possible to efficiently dissipate heat generated from a semiconductor device or the like to the outside.

1 is a schematic cross-sectional view of a dicing tape-integrated film adhesive according to an embodiment of the present invention.
2 is a schematic cross-sectional view of a dicing tape-integrated film adhesive according to another embodiment of the present invention.
3 is a diagram for explaining a method of manufacturing a semiconductor device of the present invention.

[Dicing tape integrated film adhesive]

Hereinafter, a dicing tape-integrated film adhesive of the present invention will be described. 1 is a schematic cross-sectional view of a dicing tape-integrated film adhesive according to an embodiment of the present invention. 2 is a schematic cross-sectional view of a dicing tape-integrated film adhesive according to another embodiment of the present invention.

As shown in FIG. 1, the dicing tape-integrated film adhesive 10 has a configuration in which a film adhesive 3 is laminated on a dicing tape 11. The dicing tape 11 is constituted by laminating the pressure-sensitive adhesive layer 2 on the base 1, and the film-type adhesive 3 is formed on the pressure-sensitive adhesive layer 2. In addition, the present invention may have a configuration in which the film adhesive 3'is formed only at a portion to which a work (semiconductor wafer or the like) is attached, like the dicing tape-integrated film adhesive 12 shown in FIG. 2.

The film adhesive 3 contains a thermosetting resin, a curing agent, and conductive particles, and the glass transition temperature after thermosetting is 130°C or higher. It is preferable that the glass transition temperature after the thermal curing is 140°C or higher. Further, the higher the glass transition temperature after heat curing is, the more preferable it is, but it is, for example, 300°C or less. The film adhesive 3 has heat resistance because the glass transition temperature after thermosetting is 130°C or higher. Therefore, when used in a semiconductor device, it can withstand heat generation from semiconductor elements and the like. Further, since it contains conductive particles, it becomes possible to efficiently discharge heat generated from a semiconductor element or the like to the outside. The glass transition temperature can be adjusted by adjusting the blending ratio of the thermoplastic resin and the thermosetting resin, or by adjusting the valence of the reactive functional group of a thermosetting resin such as an epoxy resin.

In addition, in this specification, the glass transition temperature after thermosetting means the glass transition temperature after heating at 140 degreeC for 1 hour, and heating at 260 degreeC for 5 hours more.

In addition, a film-like adhesive 3, the electrical resistivity at 25 ℃ after thermosetting 1 × 10 ^- is preferably ² Ω · m or less. The lower the electrical resistivity, the higher the electrical conductivity, and since the electrical conductivity is proportional to the thermal conductivity, the thermal conductivity is relatively high when the electrical resistivity at 25° C. after thermal curing is 1×10 ⁻² Ω·m or less. As a result, heat from a semiconductor element or the like can be efficiently radiated to the outside. In particular, when used in a compact and high-density mounted semiconductor device, heat can be properly radiated to the outside.

In addition, in the present specification, the electrical resistivity at 25°C after thermal curing refers to the electrical resistivity after heating at 140°C for 1 hour and heating at 260°C for 5 hours more.

Moreover, it is preferable that the storage elastic modulus at 175 degreeC after thermosetting of the film adhesive 3 is 50-1500 MPa, and it is more preferable that it is 75-1200 MPa. If the storage modulus at 175°C after heat curing is 50 MPa or more, the semiconductor element or the like can be firmly adhered to the adherend. On the other hand, if the storage modulus at 175°C after heat curing is 1500 MPa, it has a certain degree of flexibility, so it can withstand thermal stress, and peeling from the adherend can be suppressed.

In addition, in this specification, the storage modulus at 175°C after thermal curing refers to the storage modulus at 175°C after heating at 140°C for 1 hour and heating at 260°C for 5 hours more.

The storage modulus at 25°C of the film adhesive 3 is preferably ⁵ MPa or more, and more preferably 2×10 ² MPa or more. If it is less than 5 MPa, the adhesion to the dicing tape increases, and there is a tendency that the pick-up property decreases. The storage elastic modulus at 25 ℃ of the film-like adhesive agent 3 is 5 × 10 ³ is ㎫ less preferably, ³ × 10 3 ㎫ or less, and more preferably, 2.5 × 10 ³ ㎫ is less more preferred. Exceeding 5×10 ³ MPa is difficult in terms of blending.

The surface roughness (Ra) of the film adhesive 3 is preferably 0.1 to 1000 nm. Low-temperature adhesion can be improved by setting the surface roughness to 1000 nm or less. In addition, it is possible to improve the adhesion to the adherend during die attaching. In addition, it is generally difficult to make the surface roughness 0.1 nm or more.

As for the film adhesive 3, the higher the thermal conductivity at a measurement temperature of 25° C. after heat curing, the higher it is, and it is, for example, 0.5 W/m·K or more. If the thermal conductivity is 0.5W/m·K or more, heat dissipation is good, and it is possible to cope with small size and high density mounting.

In addition, in the present specification, the thermal conductivity at a measurement temperature of 25°C after heat curing refers to the thermal conductivity at 25°C after heating at 140°C for 1 hour and heating at 260°C for 5 hours more.

The film adhesive 3 is preferably 0.2 N/10 mm or more when the adhesive force is measured at 25° C. after being adhered to a wafer having a back metal film at 70°C. By making the adhesive force 0.2 N/10 mm or more, scattering of chips during dicing can be suppressed. In addition, the back metal film refers to a film in which the back metal of the wafer is deposited or plated. Since the back surface metal film usually has less surface free energy than that of a silicon wafer, the film adhesive 3 is difficult to adhere. That is, by making the adhesion of 0.2 N/10 mm or more, chip scattering during dicing can be suppressed even in the manufacture of a semiconductor device using a wafer having a backside metal film, which is difficult to adhere to the film adhesive 3, The yield is improved. The measurement of the adhesive force is a value performed under conditions of a peeling angle of 180°, a peeling temperature of 25°C, and a peeling speed of 300 mm/min.

It is preferable that the film adhesive 3 has a shear adhesion force with copper at 150° C. after holding at 0.5 MPa for 0.5 seconds at 150° C. in the range of 5 to 200 g/25 mm 2. Since the shear adhesion is 5 g/25 mm 2 or more, when bonding a semiconductor element to a lead frame, it can be sufficiently softened at 150°C or less. As a result, it is possible to prevent oxidation of an adherend such as a lead frame and to achieve high adhesion to the adherend. The method of measuring the shear adhesion is by the method described in Examples.

It is preferable that the film adhesive 3 contains a thermoplastic resin. As the thermoplastic resin, natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin , Polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, or fluorine resins. Of these thermoplastic resins, acrylic resins that contain few ionic impurities and have high heat resistance and can ensure the reliability of semiconductor devices are particularly preferred.

The acrylic resin is not particularly limited, and a polymer (acrylic copolymer) containing one or two or more esters of acrylic acid or methacrylic acid having a linear or branched alkyl group having 30 or less carbon atoms, particularly 4 to 18 carbon atoms. And the like. Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, heptyl group, cyclohexyl group, 2 -Ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, lauryl group, tridecyl group, tetradecyl group, stearyl group, octadecyl group, or dode Practical skills, etc. are mentioned.

In addition, other monomers forming the polymer (acrylic copolymer) are not particularly limited, and for example, acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, or crotonic acid. Carboxyl group-containing monomers, acid anhydride monomers such as maleic anhydride or itaconic anhydride, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, (meth) Acrylic acid 6-hydroxyhexyl, (meth) acrylic acid 8-hydroxyoctyl, (meth) acrylic acid 10-hydroxydecyl, (meth) acrylic acid 12-hydroxylauryl or (4-hydroxymethylcyclohexyl)-methylacrylic Hydroxyl group-containing monomers such as rate, styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate or (meth)acrylic Sulfonic acid group-containing monomers such as royloxynaphthalenesulfonic acid, and phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate.

Among acrylic resins, it is preferable that the weight average molecular weight is 100,000 or more, more preferably 300,000 to 3 million, and even more preferably 500,000 to 2 million. This is because adhesiveness and heat resistance are excellent in the above numerical range. In addition, the weight average molecular weight is a value measured by GPC (gel permeation chromatography) and calculated by polystyrene conversion.

The glass transition temperature of the thermoplastic resin is preferably -40°C or higher, more preferably -35°C or higher, and still more preferably -25°C or higher. Picking up can be facilitated by setting the glass transition temperature of the thermoplastic resin to -40°C or higher. Further, the glass transition temperature of the thermoplastic resin is preferably -10°C or less, and more preferably -11°C or less. By setting the glass transition temperature of the thermoplastic resin to be -10°C or less, it becomes easy to attach the film adhesive 3 to the semiconductor wafer at a low temperature of about 40°C. In the present specification, the glass transition temperature of the thermoplastic resin refers to a theoretical value obtained by the Fox equation.

The film adhesive 3 contains a thermosetting resin as described above.

Examples of the thermosetting resin include a phenol resin, an amino resin, an unsaturated polyester resin, an epoxy resin, a polyurethane resin, a silicone resin, or a thermosetting polyimide resin. In particular, an epoxy resin with little content of ionic impurities that corrodes the semiconductor device is preferable. Further, as a curing agent for an epoxy resin, a phenol resin is preferable.

The epoxy resin is not particularly limited, and for example, bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, Difunctional epoxy resins such as phenol novolak type, orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., or polyfunctional epoxy resin, or hydantoin type, trisglycidyl isocyanurate type, or Epoxy resins such as glycidylamine type are used. Of these epoxy resins, a novolac type epoxy resin, a biphenyl type epoxy resin, a trishydroxyphenylmethane type resin, or a tetraphenylolethane type epoxy resin is particularly preferable. This is because these epoxy resins are rich in reactivity with a phenol resin as a curing agent and are excellent in heat resistance and the like.

The phenolic resin acts as a curing agent for an epoxy resin, and for example, novolac-type phenols such as phenol novolak resin, phenol aralkyl resin, cresol novolak resin, tert-butylphenol novolak resin, and nonylphenol novolak resin And polyoxystyrenes such as resins, resol-type phenolic resins, and polyparaoxystyrenes. Among these phenol resins, phenol novolac resins and phenol aralkyl resins are particularly preferred. This is because the connection reliability of the semiconductor device can be improved.

The blending ratio of the epoxy resin and the phenol resin is suitably blended so that the hydroxyl group in the phenol resin is 0.5 to 2.0 equivalents per equivalent of the epoxy group in the epoxy resin component. More suitable is 0.8 to 1.2 equivalents. That is, if the blending ratio of both is out of the above range, sufficient curing reaction does not proceed, and the properties of the cured product are liable to deteriorate.

It is preferable that the film adhesive 3 contains a thermosetting resin which is solid at 25 degreeC, and a thermosetting resin which is liquid at 25 degreeC. Thereby, good low-temperature adhesion is obtained. In the present specification, a liquid phase at 25°C means that the viscosity is less than 5000 Pa·s at 25°C. Meanwhile, a solid at 25°C refers to a viscosity of 5000 Pa·s or more at 25°C. In addition, the viscosity can be measured using the model number HAAKE Roto VISCO1 manufactured by Thermo Scientific.

In the film adhesive (3), (weight of a solid thermosetting resin at 25°C)/(weight of a liquid thermosetting resin at 25°C) is preferably 49/51 to 10/90, and 45/55 to 40 It is more preferable that it is /60. By setting (weight of solid thermosetting resin at 25°C)/(weight of liquid thermosetting resin at 25°C) to 49/51 or less, it is recommended to attach the film adhesive 3 to the semiconductor wafer at a low temperature of about 40°C. It becomes easy, and low-temperature adhesion can be improved. On the other hand, by setting the (weight of the solid thermosetting resin at 25°C)/(the weight of the liquid thermosetting resin at 25°C) to 10/90 or less, the adhesiveness of the film adhesive 3 is suppressed from becoming too high, and pick-up property Can be good.

The total content of the thermoplastic resin and the curable resin in the film adhesive 3 is preferably 5% by weight or more, and more preferably 10% by weight or more with respect to the entire film adhesive 3. If it is 5% by weight or more, it is easy to maintain the shape as a film. Further, the total content of the thermoplastic resin and the curable resin is preferably 70% by weight or less, more preferably 60% by weight or less with respect to the entire film adhesive 3. When it is 70% by weight or less, electroconductive particles appropriately exhibit electroconductivity.

In the film adhesive (3), when the weight of the thermoplastic resin is A and the total weight of the thermosetting resin and the curing agent is B, the weight ratio (A)/(B) is 1/9 to 4/6 It is preferably within the range of. If the weight ratio (A)/(B) is 4/6 or less, the curing component becomes sufficient, and it becomes easy to increase the glass transition temperature after thermal curing. On the other hand, film formation becomes easy if the said weight ratio (A)/(B) is 1/9 or more.

The film adhesive 3 contains conductive particles. The conductive particles are not particularly limited, and include nickel particles, copper particles, silver particles, gold particles, aluminum particles, carbon black particles, carbon nanotubes that are fibrous particles, and particles coated with a conductive material on the surface of the core particles. I can.

The core particles may be either conductive or non-conductive, and for example, glass particles or the like may be used. Metals, such as nickel, copper, silver, gold, aluminum, can be used as a conductive material covering the surface of the core particle.

The shape of the conductive particles is not particularly limited, and for example, a flake type, a needle type, a filament type, a sphere, a scale type, or the like may be used. Among them, a flake type is preferable from the viewpoint of improving dispersibility and filling rate.

Although the average particle diameter of the said electroconductive particle is not specifically limited, 0.001 times or more (thickness of the film adhesive 3 x 0.001 or more) with respect to the thickness of the film adhesive 3 is preferable, and 0.1 times or more is more preferable. By setting it as 0.001 times or more, it is easy to increase the thermal conductivity. As a result, heat from a semiconductor element or the like can be more efficiently radiated to the outside. Moreover, the average particle diameter of the said electroconductive particle is 1 times or less with respect to the thickness of the film adhesive 3 (the thickness or less of the film adhesive 3) is preferable, and 0.8 times or less is more preferable. Chip breakage can be suppressed by setting it as 1 times or less. In addition, the average particle diameter of the conductive particles is a value obtained by using a laser diffraction particle size distribution analyzer (manufactured by HORIBA, device name; LA-910).

The specific gravity of the electroconductive particle is preferably 0.7 or more, and more preferably 1 or more. By setting it as 0.7 or more, it can suppress that electroconductive particle rises at the time of manufacture of an adhesive composition solution (varnish), and dispersion of electroconductive particle becomes non-uniform. Moreover, 22 or less are preferable and, as for the specific gravity of electroconductive particle, 21 or less are more preferable. By setting the specific gravity to 22 or less, it is possible to suppress that the electroconductive particles settle and the dispersion of the electroconductive particles becomes uneven.

The content of the conductive particles in the film adhesive 3 is preferably 30% by weight or more, and more preferably 40% by weight or more with respect to the entire film adhesive 3. Moreover, content of the said electroconductive particle becomes like this. Preferably it is 95 weight% or less, More preferably, it is 94 weight% or less. It is easy to increase thermal conductivity by making the said content of the said electroconductive particle into 30 weight% or more. As a result, heat from a semiconductor element or the like can be more efficiently radiated to the outside. On the other hand, film formation becomes easy by making the said content of the said electroconductive particle into 95 weight% or less.

In addition to the above components, the film adhesive 3 may appropriately contain a compounding agent generally used in film production, for example, a crosslinking agent.

The film adhesive 3 can be manufactured by a conventional method. For example, an adhesive composition solution containing the above components is prepared, the adhesive composition solution is applied to a base separator to a predetermined thickness to form a coating film, and then the coating film is dried to prepare a film adhesive 3 can do.

The solvent used in the adhesive composition solution is not particularly limited, but an organic solvent capable of uniformly dissolving, kneading or dispersing each of the components is preferred. For example, ketone solvents, such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, acetone, methyl ethyl ketone, and cyclohexanone, toluene, xylene, etc. are mentioned.

As the base separator, a plastic film or paper coated on the surface with a release agent such as polyethylene terephthalate (PET), polyethylene, polypropylene, a fluorine-based release agent or a long-chain alkyl acrylate-based release agent can be used. Examples of the method of applying the adhesive composition solution include roll coating, screen coating, gravure coating, and the like. In addition, the drying conditions of the coating film are not particularly limited, and for example, the drying temperature may be 70 to 160°C and the drying time may be 1 to 5 minutes.

The thickness of the film adhesive 3 is preferably 5 µm or more, and more preferably 15 µm or more. Further, the thickness of the film adhesive 3 is preferably 100 µm or less, and more preferably 50 µm or less. When the thickness of the film-type adhesive 3 is 5 μm or more, it is possible to prevent occurrence of a non-adhesive portion even if the chip is warped or the like occurs. On the other hand, if the thickness of the film adhesive 3 is 100 μm or less, it is possible to suppress the film adhesive 3 from protruding excessively due to the load during die bonding and contaminating the pad or the like.

The film adhesive 3 can be suitably used for manufacturing a semiconductor device. Among them, it can be particularly suitably used as a die attach film for bonding (die attaching) a semiconductor chip to an adherend such as a lead frame. Examples of the adherend include lead frames, interposers, and semiconductor chips. Among them, a lead frame is preferable.

It is preferable that the film adhesive 3 is integrated with a dicing tape like this embodiment, and provided as a dicing tape integrated film adhesive. However, the film adhesive of the present invention may be provided as a single film adhesive without being attached to a dicing tape. In this case, the film adhesive can have the same structure as the dicing tape integrated film adhesive by attaching to the dicing tape.

The base material 1 serves as the strength matrix of the dicing tape-integrated film adhesives 10 and 12, and preferably has ultraviolet transmittance. As the base material 1, for example, low-density polyethylene, linear polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolyprolene, polybutene, polymethylpentene, etc. Polyolefin, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, poly Polyester such as urethane, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyether ether ketone, polyimide, polyether imide, polyamide, wholly aromatic polyamide, polyphenyl sulfide, aramid (paper ), glass, glass fiber, fluororesin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, metal (foil), paper, and the like.

The surface of the substrate 1 is chemically or physically treated with conventional surface treatments such as chromic acid treatment, ozone exposure, flame exposure, high pressure electric shock exposure, ionizing radiation treatment, etc., in order to increase adhesion and retention with adjacent layers. Treatment and coating treatment with a primer (for example, an adhesive substance to be described later) can be performed.

The thickness of the substrate 1 is not particularly limited and can be appropriately determined, but is generally about 5 to 200 μm.

The pressure-sensitive adhesive used to form the pressure-sensitive adhesive layer 2 is not particularly limited, and for example, general pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives and rubber-based pressure-sensitive adhesives can be used. As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive having an acrylic polymer as a base polymer is preferable from the viewpoint of clean cleaning property of an electronic component in which contamination of semiconductor wafers and glass should be avoided with ultrapure water or an organic solvent such as alcohol.

As the acrylic polymer, for example, (meth)acrylate alkyl ester (e.g., methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester , Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester, Linear or branched alkyl esters of 1 to 30 carbon atoms, especially 4 to 18 carbon atoms of an alkyl group such as hexadecyl ester, octadecyl ester, eicosyl ester, and cycloalkyl (meth)acrylates (e.g., cyclopentyl esters) , Cyclohexyl ester, etc.), and an acrylic polymer in which one or two or more of them are used as a monomer component. In addition, (meth)acrylic acid ester means an acrylic acid ester and/or a methacrylic acid ester, and (meth) of this invention has the same meaning all.

The acrylic polymer may contain a unit corresponding to another monomer component copolymerizable with the alkyl (meth)acrylate or cycloalkyl ester, if necessary, for the purpose of modifying cohesive strength and heat resistance. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; Acid anhydride monomers such as maleic anhydride and itaconic anhydride; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, Hydroxyl group-containing monomers such as 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl (meth)acrylate; Sulfonic acid groups such as styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid Containing monomers; Phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate; Acrylamide, acrylonitrile, etc. are mentioned. One or two or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers is preferably 40% by weight or less of the total monomer components.

In addition, in order to crosslink the acrylic polymer, a polyfunctional monomer or the like may be included as a monomer component for copolymerization, if necessary. As such a polyfunctional monomer, for example, hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) Acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate , Polyester (meth)acrylate, urethane (meth)acrylate, and the like. One or two or more of these polyfunctional monomers can also be used. The amount of the polyfunctional monomer to be used is preferably 30% by weight or less of all monomer components from the viewpoint of adhesive properties and the like.

The acrylic polymer is obtained by polymerizing a single monomer or a mixture of two or more types of monomers. The polymerization can be carried out in any of solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, and the like. It is preferable that the content of the low molecular weight substance is small from the viewpoint of prevention of contamination to a clean adherend. In this respect, the number average molecular weight of the acrylic polymer is preferably 300,000 or more, more preferably about 400,000 to 3 million.

Further, for the pressure-sensitive adhesive, an external crosslinking agent may be appropriately employed in order to increase the number average molecular weight of the acrylic polymer as the base polymer. As a specific means of the external crosslinking method, a method of reacting by adding a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, and a melamine-based crosslinking agent can be mentioned. In the case of using an external crosslinking agent, its amount is appropriately determined depending on the balance with the base polymer to be crosslinked, and further according to the use as an adhesive. In general, about 5 parts by weight or less, and more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the base polymer. Further, for the pressure-sensitive adhesive, if necessary, additives such as various conventionally known tackifiers and anti-aging agents may be used in addition to the above components.

The pressure-sensitive adhesive layer 2 can be formed by a radiation curable pressure-sensitive adhesive. The radiation-curable pressure-sensitive adhesive can increase the degree of crosslinking by irradiation with radiation such as ultraviolet rays, and thus its adhesive strength can be easily reduced.

By irradiating only the portion 2a corresponding to the work attachment portion of the pressure-sensitive adhesive layer 2 shown in FIG. 1, the difference in adhesive strength with the other portions 2b can be made. In this case, the portion 2b formed by the uncured radiation-curable pressure-sensitive adhesive is adhered to the film-type adhesive 3 to secure a holding power during dicing.

In addition, by curing the radiation-curable pressure-sensitive adhesive layer 2 in accordance with the film-type adhesive 3'shown in FIG. 2, the above-described portion 2a having a remarkably reduced adhesive strength can be formed. In this case, the wafer ring can be fixed to the portion 2b formed by the uncured radiation-curable adhesive.

That is, in the case of forming the pressure-sensitive adhesive layer 2 by a radiation-curable pressure-sensitive adhesive, the pressure-sensitive adhesive strength of the portion 2a in the pressure-sensitive adhesive layer 2 <the adhesive force of the other portions 2b, so that the portion 2a It is preferable to irradiate it.

The radiation-curable pressure-sensitive adhesive has a radiation-curable functional group such as a carbon-carbon double bond, and can be used without any particular limitation to exhibit adhesiveness. Examples of the radiation-curable pressure-sensitive adhesive include an additive-type radiation-curable pressure-sensitive adhesive in which a radiation-curable monomer component or an oligomer component is mixed with a general pressure-sensitive adhesive such as the acrylic pressure-sensitive adhesive and rubber-based pressure-sensitive adhesive.

As the radiation curable monomer component to be blended, for example, urethane oligomer, urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylol methane tetra (meth) acrylate, pentaerythritol tri (meth) acrylic Rate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanedioldi(meth)acrylate, etc. Can be lifted. Further, the radiation curable oligomer component includes various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based, and the molecular weight is suitably in the range of about 100 to 30000. The amount of the radiation-curable monomer component and the oligomer component to be blended can appropriately determine an amount capable of lowering the adhesive strength of the adhesive layer according to the type of the adhesive layer. In general, it is, for example, 5 to 500 parts by weight, preferably about 40 to 150 parts by weight, based on 100 parts by weight of a base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

In addition, as the radiation-curable pressure-sensitive adhesive, in addition to the above-described addition-type radiation-curable pressure-sensitive adhesive, as a base polymer, an intrinsic radiation-curable pressure-sensitive adhesive using one having a carbon-carbon double bond in the side chain or main chain of the polymer, or at the end of the main chain may be mentioned. Since the intrinsic radiation-curable adhesive does not need or does not contain a low molecular weight oligomer component, etc., the oligomer component, etc., does not move in the adhesive over time and forms a pressure-sensitive adhesive layer having a stable layer structure. It is desirable because it can be done.

As the base polymer having a carbon-carbon double bond, one having a carbon-carbon double bond and having adhesiveness can be used without particular limitation. As such a base polymer, it is preferable to have an acrylic polymer as a basic skeleton. As a basic skeleton of an acrylic polymer, the acrylic polymer mentioned above can be mentioned.

The method of introducing the carbon-carbon double bond into the acrylic polymer is not particularly limited, and various methods can be employed, but the introduction of the carbon-carbon double bond into the polymer side chain facilitates molecular design. For example, after copolymerizing a monomer having a functional group to an acrylic polymer in advance, a functional group capable of reacting with the functional group and a compound having a carbon-carbon double bond are condensed while maintaining the radiation curability of the carbon-carbon double bond. Or a method of making an addition reaction is mentioned.

Examples of combinations of these functional groups include a carboxylic acid group and an epoxy group, a carboxylic acid group and an aziridyl group, a hydroxyl group and an isocyanate group. Among the combinations of these functional groups, a combination of a hydroxyl group and an isocyanate group is suitable from the viewpoint of easiness of tracking the reaction. In addition, if a combination of these functional groups produces an acrylic polymer having a carbon-carbon double bond, the functional group may be on either side of the acrylic polymer and the compound, but in the preferred combination, the acrylic polymer has a hydroxyl group. And the compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, and the like. I can. Further, as the acrylic polymer, a copolymer of the above-described hydroxy group-containing monomer, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and an ether compound of diethylene glycol monovinyl ether is used.

The intrinsic radiation curable pressure-sensitive adhesive may use the base polymer having a carbon-carbon double bond (especially an acrylic polymer) alone, but the radiation curable monomer component or oligomer component may be blended to the extent that the properties are not deteriorated. . The radiation curable oligomer component or the like is usually in the range of 30 parts by weight, preferably 0 to 10 parts by weight, based on 100 parts by weight of the base polymer.

The radiation curable pressure-sensitive adhesive contains a photopolymerization initiator when cured by ultraviolet rays or the like. As a photoinitiator, for example, 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2- Α-ketol compounds such as hydroxypropiophenone and 1-hydroxycyclohexylphenyl ketone; Methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane Acetophenone compounds such as -1; Benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether; Ketal compounds such as benzyl dimethyl ketal; Aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; Photoactive oxime compounds such as 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime; Benzophenone compounds such as benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone; Thioxanthone, 2-chloro thioxanthone, 2-methyl thioxanthone, 2,4-dimethyl thioxanthone, isopropyl thioxanthone, 2,4-dichloro thioxanthone, 2,4-diethyl thioxanthone Thioxanthone compounds such as santon and 2,4-diisopropyl thioxanthone; Campoquinone; Halogenated ketones; Acylphosphine oxide; Acyl phosphonate, etc. are mentioned. The blending amount of the photopolymerization initiator is, for example, about 0.05 to 20 parts by weight based on 100 parts by weight of a base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

In addition, as the radiation-curable pressure-sensitive adhesive, for example, a photopolymerizable compound such as an addition polymerizable compound having two or more unsaturated bonds and an alkoxysilane having an epoxy group disclosed in Japanese Patent Laid-Open No. 60-196956, and carbonyl And rubber-based adhesives and acrylic adhesives containing photopolymerization initiators such as compounds, organic sulfur compounds, peroxides, amines, and onium salt-based compounds.

In the radiation-curable pressure-sensitive adhesive layer 2, if necessary, a compound to be colored by irradiation with radiation may be contained. By including the compound to be colored by radiation irradiation in the pressure-sensitive adhesive layer 2, only the irradiated portion can be colored. The compound to be colored by irradiation with radiation is colorless or pale color before irradiation with radiation, but is a compound that becomes colored by irradiation with radiation, and examples thereof include leuco dyes. The ratio of use of the compound to be colored by irradiation with radiation can be appropriately set.

The thickness of the pressure-sensitive adhesive layer 2 is not particularly limited, but is preferably about 1 to 50 µm from the viewpoint of preventing notch on the chip cut surface and the compatibility of fixing and holding the adhesive layer. Preferably, 2 to 30 μm and 5 to 25 μm are more preferable.

It is preferable that the film adhesives 3 and 3'of the dicing tape integrated film adhesives 10 and 12 are protected by a separator (not shown). The separator has a function as a protective material that protects the film adhesives 3 and 3'until it is provided for practical use. The separator is peeled off when attaching the work onto the film adhesives 3 and 3'of the dicing tape integrated film adhesive. As the separator, a plastic film or paper coated on the surface with a release agent such as polyethylene terephthalate (PET), polyethylene, polypropylene, a fluorine-based release agent, or a long-chain alkyl acrylate-based release agent can also be used.

The dicing tape-integrated film adhesives 10 and 12 can be manufactured by a conventional method. For example, by bonding the pressure-sensitive adhesive layer 2 of the dicing tape 11 and the film adhesives 3 and 3', the dicing tape-integrated film adhesives 10 and 12 can be manufactured.

In the dicing tape-integrated film adhesive 10, 12, the peeling force of the film adhesive 3, 3'and the dicing tape 11, peeling rate: 300 mm/min, peeling temperature: 25°C, It is preferable that it is in the range of 0.01-3.00N/20mm, and it is more preferable that it is in the range of 0.02-2. If the peeling force is 0.01N/20mm or more, scattering of chips during dicing can be suppressed. In addition, if the peeling force is 3.00N/20mm or less, pickup can be facilitated.

[Semiconductor device manufacturing method]

The method for manufacturing a semiconductor device according to the present embodiment,

Step A of attaching a semiconductor wafer to the film adhesive of the dicing tape integrated film adhesive,

Step B of dicing the semiconductor wafer together with the film adhesive,

Step C of picking up a semiconductor element equipped with a film adhesive obtained by dicing, and

Step D of maintaining the film-type adhesive in the range of 0.05 to 40 MPa for 0.01 to 2 seconds in the range of 50 to 150°C after contacting the semiconductor device with the film-type adhesive to an adherend, and

After the step D, at least a step E of thermosetting the film adhesive is provided.

Hereinafter, a case of manufacturing a semiconductor device using the dicing tape-integrated film adhesive 10 will be described with reference to FIG. 3 with respect to the method of manufacturing a semiconductor device according to the present embodiment. 3 is a diagram for explaining a method of manufacturing a semiconductor device of the present invention.

First, the semiconductor wafer 4 is pressed onto the semiconductor wafer attachment portion 3a of the film adhesive 3 in the dicing tape integrated film adhesive 10, and adhered and held to fix it (attachment process, Step A). This step is performed while pressing by a pressing means such as a pressing roll. At this time, it can be compressed at a low temperature of about 40°C. Specifically, the compression bonding temperature (attachment temperature) is preferably 35°C or higher, and more preferably 37°C or higher. The upper limit of the pressing temperature is preferably lower, preferably 50°C or less, more preferably 45°C or less, and still more preferably 43°C or less. Since it can adhere to the semiconductor wafer 4 at a low temperature of about 40° C., heat influence on the semiconductor wafer 4 can be prevented, and warpage of the semiconductor wafer 4 can be suppressed.

The pressure during the compression bonding is preferably 1×10 ⁵ to 1×10 ⁷ Pa, more preferably 2×10 ⁵ to 8×10 ⁶ Pa. In addition, the time for the pressing is preferably 1 second to 5 minutes, more preferably 1 minute to 3 minutes.

Next, the semiconductor wafer 4 is diced together with the film adhesive 3 (Step B). In this way, the semiconductor wafer 4 is cut into a predetermined size and divided into pieces to manufacture the semiconductor chip 5. Dicing is performed, for example, from the circuit surface side of the semiconductor wafer 4 according to a conventional method. In addition, in this process, for example, a cutting method called full cut in which a cutout is formed up to the dicing tape-integrated film adhesive 10 can be adopted. The dicing apparatus used in this step is not particularly limited, and a conventionally known one can be used. In addition, since the semiconductor wafer 4 is bonded and fixed by the dicing tape-integrated film adhesive 10, not only can chip cutout and chip scattering can be suppressed, but also breakage of the semiconductor wafer 4 can be suppressed.

Next, in order to peel the semiconductor chip 5 adhered and fixed to the dicing tape integrated film adhesive 10, the semiconductor chip 5 is picked up (step C). The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, an individual semiconductor chip 5 is pushed up from the side of the dicing tape-integrated film adhesive 10 with a needle, and the pushed up semiconductor chip 5 is picked up by a pickup device. .

Here, when the pressure-sensitive adhesive layer 2 is an ultraviolet-curable type, the pick-up is performed after irradiating the pressure-sensitive adhesive layer 2 with ultraviolet rays. Thereby, the adhesive force of the pressure-sensitive adhesive layer 2 to the film adhesive 3 is lowered, and the semiconductor chip 5 provided with the film adhesive 3 becomes easy to peel. As a result, pickup is possible without damaging the semiconductor chip 5. Conditions such as irradiation intensity and irradiation time during UV irradiation are not particularly limited, and may be appropriately set as necessary.

The picked up semiconductor chip 5 is bonded and fixed to the adherend 6 via a film adhesive 3 (die attach, step D). At this time, after contacting the semiconductor device 5 provided with the film-type adhesive to the adherend 6, the film-type adhesive 3 is in the range of 50 to 150°C (preferably in the range of 80 to 140°C) At 0.01 to 2 seconds (preferably 0.02 to 1.5 seconds) within the range of 0.05 to 40 MPa (preferably 0.1 to 30 MPa). Thereby, the film adhesive 3 can be sufficiently softened and can be brought into close contact. Since the temperature below 150°C softens the film adhesive 3 at a relatively low temperature, oxidation of the adherend 6 can be prevented.

Subsequently, the film adhesive 3 is thermally cured (step E). Thereby, the semiconductor chip 5 and the adherend 6 are bonded together. The heating temperature during thermal curing is preferably 100°C or higher, and more preferably 120°C or higher. The heating temperature at the time of thermal curing is preferably 350°C or less, and more preferably 300°C or less. If the heating temperature is within the above range, good adhesion can be achieved.

Next, a wire bonding step of electrically connecting the distal end of the terminal portion (inner lead) of the adherend 6 and the electrode pad (not shown) on the semiconductor chip 5 with the bonding wire 7 is performed. As the bonding wire 7, for example, a gold wire, an aluminum wire, or a copper wire is used. The temperature at the time of wire bonding is preferably 80°C or higher, more preferably 120°C or higher, and the temperature is preferably 250°C or lower, and more preferably 175°C or lower. In addition, the heating time is performed for several seconds to several minutes (for example, 1 second to 1 minute). The connection is performed by combining vibration energy by ultrasonic waves and compression energy by applying pressure while heated to fall within the above temperature range.

Subsequently, the sealing process of sealing the semiconductor chip 5 with the sealing resin 8 is performed. This step is performed in order to protect the semiconductor chip 5 and the bonding wire 7 mounted on the adherend 6. This step is performed by molding the sealing resin into a mold. As the sealing resin 8, for example, an epoxy resin is used. The heating temperature at the time of resin sealing is preferably 165°C or higher, more preferably 170°C or higher, and the heating temperature is preferably 185°C or lower, and more preferably 180°C or lower.

If necessary, the sealing material may be further heated (post-curing step). This makes it possible to completely cure the sealing resin 8 that is insufficiently cured in the sealing process. The heating temperature can be appropriately set.

Example

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited to the following examples unless departing from the gist of the present invention. In addition, in each example, all parts are based on weight unless otherwise specified.

The components used in the examples will be described.

Teisan Resin SG-70L (acrylic copolymer, Mw: 900,000, glass transition temperature: -13°C): manufactured by Nagase Chemtex Co., Ltd.

EOCN-1020-4 (a solid epoxy resin at 25°C): manufactured by Nippon Kayaku Co., Ltd.

HP-4700 (solid epoxy resin at 25°C): manufactured by DIC

HP-4032D (liquid epoxy resin at 25°C): manufactured by DIC

JER828 (liquid epoxy resin at 25°C): manufactured by Mitsubishi Chemical Co., Ltd.

MEH-8000H (phenolic resin as a curing agent): manufactured by Meiwa Kasei Co., Ltd.

1400YP (conductive particles, copper powder, average particle diameter: 7 μm): manufactured by Mitsui Kinzoku Kogyo

SPH02J (conductive particles, silver powder, average particle diameter: 1 μm): manufactured by Mitsui Kinzoku Kogyo

TPP-K (hardening accelerator): manufactured by Hokko Chemical Co., Ltd.

Examples and Comparative Examples

According to the mixing ratio shown in Table 1, each component and solvent (methyl ethyl ketone) shown in Table 1 were put into a stirring kiln of a hybrid mixer (HM-500 manufactured by Keyence), and stirred and mixed in a stirring mode for 3 minutes. The obtained varnish was applied to a release-treated film (MRA50 manufactured by Mitsubishi Corporation) and then dried to prepare a film adhesive. The thickness of each film adhesive is shown in Table 1. In addition, in Table 1, the weight ratio (A)/(B) when the weight of the thermoplastic resin is A, the total weight of the thermosetting resin and the curing agent is B, and the content of the conductive particles to the entire film adhesive (% by weight) ) Is also shown.

The obtained film adhesive was cut into a circular shape having a diameter of 230 mm, and adhered on the pressure-sensitive adhesive layer of a dicing tape (P2130G manufactured by Nitto Denko Corporation) at 25°C to prepare a dicing tape-integrated film adhesive.

A silicon wafer (made by Shin-Etsu Chemical Co., Ltd., thickness 0.6 mm) was ground to a thickness of 0.2 mm using a bag grinder (DFG-8560 manufactured by DISCO, Inc.). Next, Ti (titanium) was deposited to a thickness of 200 nm on the grinding surface. Next, Ni (nickel) was deposited on the Ti layer to a thickness of 200 nm. Next, Ag (silver) was deposited on the Ni layer to a thickness of 300 nm. As described above, a wafer provided with a back metal film was produced.

The following evaluation was performed using the obtained film adhesive, the dicing tape integrated film adhesive, and the wafer provided with the back side metal film. The results are shown in Table 2.

[Measurement of glass transition temperature after thermosetting, and measurement of storage modulus at 175°C after thermosetting]

The film adhesive was superimposed on the film adhesive until the thickness became 500 μm. Then, it was heated at 140° C. for 1 hour and further heated at 260° C. for 5 hours to heat cure. Next, a rectangle having a length of 22.5 mm (measurement length) and a width of 10 mm was cut with a cutter knife, and the storage modulus at -50 to 300°C was measured using a solid viscoelasticity measuring device (RSAII, manufactured by Rheometric Scientific Co., Ltd.). Measured. Measurement conditions were a frequency of 1 Hz and a temperature increase rate of 10°C/min. The value at 175°C at that time was taken as the measured value of the storage modulus at 175°C after heat curing. Further, the glass transition temperature was obtained by calculating the value of tan δ (E" (loss modulus)/E' (storage modulus)), and the results are shown in Table 2.

[Measurement of electrical resistivity at 25°C after heat curing]

The film adhesives of Examples and Comparative Examples were heated at 140° C. for 1 hour and further heated at 260° C. for 5 hours to thermally cure. Next, the measurement was performed by a four-terminal method using a circuit element measuring instrument (Hioki Denki Co., Ltd., Milliohm High Tester AC3560). The results are shown in Table 2.

[Measurement of peel force between film adhesive and dicing tape]

After bonding a polyester adhesive tape (BT-315 manufactured by Nitto Denko Co., Ltd.) on the film adhesive of the dicing tape-integrated film adhesive for maintenance purposes, it was cut into a width of 100 mm x 100 mm to prepare a sample. I did. With respect to this sample, the film adhesive was peeled from the dicing tape with a T-type peeling tester at a peeling rate of 300 mm/min and a peeling temperature of 25°C, and peeling force was measured. The results are shown in Table 2.

[Measurement of shear adhesion with copper]

The film adhesives of Examples and Comparative Examples were bonded to silicon having a thickness of 500 μm and 5 mm×5 mm at 60°C to prepare a chip for measuring shear adhesion. The adhesive side of this measurement chip was bonded to a copper plate by holding 0.5 MPa for 0.5 seconds at 150°C. As the copper plate, a copper plate (JIS standard C1020) having a thickness of 200 μm was used. This sample for measurement was subjected to a shear tester (manufactured by Dage, Dage 4000) to measure the shear adhesion between the film adhesive and copper. The shear test conditions were 500 µm/s, a measurement gap of 100 µm, and a stage temperature of 150°C. The case where the shear adhesion was in the range of 5 to 200 g/25 mm 2 was evaluated as "○", and the case outside the range of 5 to 200 g/25 mm 2 was evaluated as "×". Table 2 shows the results together with the measured values.

[Heat resistance evaluation]

The wafer metal film provided with the back metal film prepared above was bonded to the film adhesive side of the dicing tape integrated film adhesive produced above. Bonding was performed using a wafer mounter (manufactured by Nitto Seiki) MA-3000III at an adhesion rate of 10 mm/min and an adhesion temperature of 70°C. Next, dicing was performed with a dicing machine to obtain a chip with a 5 x 5 mm film adhesive. Then, it was die-attached to a copper lead frame (manufactured by Dai Nippon Instsu Corporation, product names: QFN32, 64) with a die bonder. Die attach conditions were temperature: 150 degreeC, holding time: 0.5 second, and pressure: 0.5 MPa. Thereafter, after holding at 140° C. for 1 hour, heating at 260° C. for 5 hours to heat cure the film adhesive. Then, it sealed with a sealing resin (made by Hitachi Kasei Co., Ltd., GE7470), and heated at 175 degreeC for 5 hours, and the sealing resin was hardened. Then, it cut into 8x8mm and obtained the package.

Ten packages prepared above were subjected to a thermal cycle test of 1000 cycles at a temperature: -55 to 125°C. The test was performed in accordance with JEDEC standard 22-A104C condition B.

After the thermal cycle, the package was observed with an ultrasonic microscope, and the case where even one peeling of the chip was observed was evaluated as x, and the case where peeling was not observed in all ten was evaluated as ○. The results are shown in Table 2.

1: description
2: adhesive layer
3, 3': film adhesive
4: semiconductor wafer
5: semiconductor chip
6: adherend
7: bonding wire
8: sealing resin
10, 12: dicing tape integrated film adhesive
11: dicing tape

Claims (10)

Including a thermosetting resin, a curing agent and conductive particles,
The glass transition temperature after heat curing is 130°C or higher,
A film adhesive for semiconductor devices, characterized in that the electrical resistivity at 25°C after heat curing is 1×10 ^-2 Ω·m or less. delete The method of claim 1,
Containing a thermoplastic resin,
When the weight of the thermoplastic resin is A and the total weight of the thermosetting resin and the curing agent is B, the weight ratio (A)/(B) is in the range of 1/9 to 4/6. glue. The method of claim 1,
A film adhesive, wherein the content of the conductive particles is 30 to 95% by weight based on the entire film adhesive. The method of claim 1,
A film adhesive having a tensile storage modulus of 50 to 1500 MPa at 175°C after heat curing. The method of claim 1,
A film adhesive having a shear adhesion to copper at 150° C. of 5 to 200 g/25 mm 2 after holding at 0.5 MPa for 0.5 seconds at 150° C. The method according to any one of claims 1 and 3 to 6,
Film-type adhesive, characterized in that the thickness is in the range of 5 to 100㎛. A dicing tape in which an adhesive layer is laminated on a substrate,
Having the film adhesive according to claim 1,
Dicing tape integrated film adhesive, characterized in that the film adhesive is formed on the pressure-sensitive adhesive layer. According to claim 8
A die, characterized in that the peeling force between the film adhesive and the dicing tape is in the range of 0.01 to 3.00 N/20 mm under conditions of a peel rate: 300 mm/min, peel temperature: 25° C., and a T-type peel tester Sing tape integrated film adhesive. It is a manufacturing method of a semiconductor device using the dicing tape-integrated film adhesive according to claim 8 or 9,
Step A of attaching a semiconductor wafer to the film adhesive of the dicing tape integrated film adhesive,
Step B of dicing the semiconductor wafer together with the film adhesive,
Step C of picking up a semiconductor element equipped with a film adhesive obtained by dicing, and
Step D of maintaining the film-type adhesive in the range of 0.05 to 40 MPa for 0.01 to 2 seconds in the range of 50 to 150°C after contacting the semiconductor device with the film-type adhesive to an adherend, and
A method for manufacturing a semiconductor device, comprising a step E of thermosetting the film adhesive after the step D.

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