JP2010265416A - Film adhesive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film adhesive used in a dicing step and a die-bonding step of a semiconductor wafer, which film adhesive ensures the alignment of a bump of a chip and a terminal of a substrate after picking up the chip. <P>SOLUTION: The film adhesive 100 is obtained by sequentially laminating an adhesive layer 12, a thermosetting resin layer 30, and a second plastic layer 20 on a first plastic layer 10, wherein the area of the adhesive layer is bigger than the area of the thermosetting resin layer, and the thermosetting resin layer has parallel transmittance of visible light of 15-100% when uncured. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a film adhesive.

  In general, semiconductor chips are directly mounted on a circuit board by face-down bonding, and solder bumps are formed on the electrodes of the semiconductor chip and soldered to the circuit board. Alternatively, conductive bonding is applied to the protruding electrodes provided on the semiconductor chip. A method of applying an agent and making an electrical connection to a circuit board electrode is known.

  In these systems, when exposed to various environments, there is a problem that connection reliability is lowered because stress based on the difference in thermal expansion coefficient between the chip to be connected and the substrate is generated at the connection interface. For this reason, a method of filling the gap between the chip and the substrate with an underfill material such as an epoxy resin is generally studied for the purpose of reducing the stress at the connection interface.

  The underfill material filling method includes a method of injecting a low-viscosity liquid resin after connecting the chip and the substrate, and a method of mounting the chip after placing the underfill material on the substrate. On the other hand, there are a method of applying a liquid resin and a method of attaching a film-like resin as a method of mounting a chip after an underfill material is previously installed on a substrate.

  However, in the application of liquid resin, it is difficult to precisely control the application amount with a dispenser. In recent chip thinning, since the amount of coating is too large, the resin that exudes during bonding scoops up the side of the chip and contaminates the bonding tool, necessitating cleaning of the tool, making the mass production process complicated It is the cause.

  In addition, in the case of pasting a film-like resin, it is easy to make the optimum resin amount by controlling the thickness of the resin, but when pasting the film on the substrate, a film pasting process called a temporary crimping process is required. is there. In the pre-bonding process, a “reel-shaped tape” slit to a width larger than the target chip width is used, and the adhesive on the substrate is half-cut according to the chip size, so that the adhesive does not react Affix to the substrate by thermocompression bonding at temperature.

  However, the accuracy of supplying the film to the chip mounting position is poor, and in order to ensure the yield, it is common that the film attached by temporary pressure bonding is larger than the chip size. For this reason, it is necessary to allow a sufficient distance from the adjacent parts, which hinders high density mounting. In addition, it is difficult to process a narrow reel corresponding to a minute chip or the like.

  Furthermore, since it takes too much time to perform each of these operations on each of the flip-chip connected elements, it can be said that there are problems in terms of processes.

  For this reason, as a method of supplying a film-like adhesive of the same size as the chip size and reducing the number of processes, the adhesive can be processed simultaneously with chip processing by back grinding, dicing, etc. after supplying the adhesive in the wafer state. A method has been proposed for obtaining a chip with an adhesive. (See Patent Document 1)

  An integrated film adhesive in which a dicing adhesive film and a die bonding adhesive film are bonded together is also known (see Patent Document 2).

JP 2006-049482 A JP 2007-123914 A

  However, the adhesive film as described above has a problem that the wafer is damaged or the bonding adhesive film is peeled off from the chip when the chip is picked up by the flip chip bonder. Furthermore, there are the following problems depending on the degree of visible light permeability of the adhesive film. That is, when connecting the terminal (bump) of the chip and the terminal of the substrate, the alignment between the chip and the substrate is performed by visually observing the marks provided on them, but the visible light permeability of the adhesive film is insufficient. If it exists, it becomes difficult to perform alignment.

  Accordingly, an object of the present invention is a film-like adhesive used in a semiconductor wafer dicing process and a die bonding process, and after the chip is picked up, the chip bump and the substrate terminal are reliably aligned. It is in providing the film adhesive which can be manufactured.

  The present invention is a film adhesive in which an adhesive layer, a thermosetting resin layer, and a second plastic layer are laminated in this order on a first plastic layer, and the area of the adhesive layer is thermoset. The thermosetting resin layer provides a film adhesive having a visible light parallel transmittance of 15 to 100% when uncured. In addition, the area of an adhesive layer and a thermosetting resin layer means the area of a main surface.

  Since the thermosetting resin layer has visible light permeability, the film adhesive of the present invention has a flip chip bonder chip when connecting the bump on the chip circuit surface and the terminal on the substrate side facing the chip circuit surface in flip chip mounting. And positioning of the substrate can be ensured.

  The film adhesive of the present invention preferably includes a release layer between the second plastic layer and the thermosetting resin layer. By forming the release layer, the second plastic layer can be easily peeled from the thermosetting resin layer when the wafer is attached to the film adhesive.

  In the present invention, it is preferable that the 90 ° peel peeling force between the pressure-sensitive adhesive layer and the thermosetting resin layer is 50 N / m or less at both peeling speeds of 300 mm / min and 500 mm / min. By adopting such a configuration, sufficient adhesion between the pressure-sensitive adhesive layer and the thermosetting resin layer can be ensured, and chip peeling from the film adhesive during wafer dicing can be prevented. On the other hand, the affinity between the adhesive layer and the thermosetting resin layer is not too high, and the peel force is kept low, so even if a flip chip bonder is used to pick up the chip, the chip is securely Can be picked up.

  The thermosetting resin layer preferably has a thickness of 5 to 100 μm. Thereby, insufficient embedding of the wafer circuit surface around the protruding connection terminal can be suppressed, and generation of voids can be suppressed.

  The thermosetting resin layer preferably comprises at least a polymer resin, a curable monomer, and a latent curing agent. Thereby, it is possible to allow time for reading the alignment mark when the chip and the substrate are aligned by the flip chip bonder.

  According to the present invention, a film-like adhesive used in a semiconductor wafer dicing process and a die-bonding process, which can reliably align the chip and the substrate after picking up the chip. Can provide.

It is a perspective view of the film adhesive concerning a first embodiment. It is sectional drawing along the II-II line of FIG. It is sectional drawing of the film adhesive which concerns on 2nd embodiment.

  Hereinafter, the film adhesive according to a preferred embodiment will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. In addition, the drawings are partially exaggerated for easy understanding, and dimensional ratios do not necessarily match those described.

  FIG. 1 is a perspective view of a film adhesive according to the first embodiment, and FIG. 2 is a cross-sectional view taken along line II-II in FIG. A film adhesive 100 according to the first embodiment shown in FIG. 1 includes a pressure-sensitive adhesive layer 12 between a first plastic layer 10 and a second plastic layer 20 facing each other. As shown, a thermosetting resin layer 30 is formed between the pressure-sensitive adhesive layer 12 and the second plastic layer 20.

  As shown in FIG. 2, the film adhesive 100 covers the second plastic layer 20, the thermosetting resin layer 30 formed on the second plastic layer 20, and the thermosetting resin layer 30. The pressure-sensitive adhesive layer 12 formed on the second plastic layer 20 and the first plastic layer 10 formed on the pressure-sensitive adhesive layer 12 are provided.

  FIG. 3 is a cross-sectional view of the film adhesive according to the second embodiment. The film adhesive 110 according to the second embodiment shown in FIG. 2 is a film according to the first embodiment except that a release layer 40 is provided between the second plastic layer 20 and the thermosetting resin layer 30. It has the same configuration as the adhesive. That is, as shown in FIG. 3, the film adhesive 110 was formed on the second plastic layer 20, the release layer 40 formed on the second plastic layer 20, and the release layer 40. The thermosetting resin layer 30, the pressure-sensitive adhesive layer 12 formed on the second plastic layer 20 so as to cover the thermosetting resin layer 30, and the first plastic layer 10 formed on the pressure-sensitive adhesive layer 12 And. In some cases, the first plastic layer 10 and the pressure-sensitive adhesive layer 12 may be provided as a single unit. In this case, the laminate of the first plastic layer 10 and the pressure-sensitive adhesive layer 12 is referred to as a dicing tape 14 (FIG. 1-3).

  Examples of the first plastic layer 10 and the second plastic layer 20 include polyester films such as polyethylene terephthalate films, polytetrafluoroethylene films, polyethylene films, polypropylene films, polymethylpentene films, and polyolefin films such as polyvinyl acetate films. A plastic film such as a polyvinyl chloride film or a polyimide film can be used, and these may have a multilayer structure.

  The thickness of the first plastic layer 10 is appropriately selected within a range that does not impair workability. However, when a high energy ray (in particular, ultraviolet ray) curable pressure sensitive adhesive is used as the pressure sensitive adhesive constituting the pressure sensitive adhesive layer 12, the thickness does not hinder the transmission of the high energy ray. Usually, it is 10-500 micrometers, Preferably it is 50-200 micrometers.

  In order to improve the adhesion between the first plastic layer 10 and the pressure-sensitive adhesive layer 12, the surface of the first plastic layer 10 is subjected to chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. Chemical or physical surface treatment may be applied.

  As the second plastic layer 20, a film made of a fluororesin and having a low surface energy can be used. As such a film, for example, A-63 (mold release treatment agent: modified silicone type) manufactured by Teijin DuPont Films Co., Ltd. or A-31 (mold release treatment agent: Pt type products) manufactured by Teijin DuPont Films Ltd. Silicone type).

  In order to keep the peeling force between the second plastic layer 20 and the thermosetting resin layer 30 low, as shown in FIG. 3, a silicone-type release agent, a fluorine-type release agent, and a long-chain alkyl acrylate-type release layer are provided between the layers. It is preferable to provide a release layer 40 composed of a release agent such as an agent.

  The thickness of the second plastic layer 20 is appropriately selected within a range that does not impair workability. Usually, it is 100 micrometers or less, Preferably it is 10-75 micrometers, More preferably, it is 25-50 micrometers.

  Examples of the thermosetting resin constituting the thermosetting resin layer 30 include those having a film forming property such as an acrylic rubber resin, a polyimide resin, and a phenoxy resin as the base resin, and epoxy resins and bismaleimides as the thermosetting component. Examples thereof include a resin, a triazine resin, a phenol resin and the like that are cured by heat. The thermosetting resin may further contain a curing agent that reacts with the thermosetting component, and may be encapsulated by coating the curing agent with a polyurethane-based or polyester-based polymer substance to increase the curing time. .

  In order to increase the adhesive strength between the thermosetting resin layer 30 and the wafer, a coupling agent may be included, and examples of the coupling agent include silane, titanium, and aluminum. Examples of the silane coupling agent include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, 3-aminopropylmethyldisilane. Examples include ethoxysilane, 3-ureidopropyltriethoxysilane, and 3-ureidopropyltrimethoxysilane, which can be used alone or in combination of two or more.

  From the viewpoint of controlling fluidity and improving the elastic modulus, a filler may be added to the thermosetting resin to such an extent that the above-described transmittance can be maintained. Examples of the filler include 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, and crystallinity. Examples thereof include composite oxides such as silica, amorphous silica, mullite and cordierite, montmorillonite and smectite, and the shape of the filler is not particularly limited. These fillers can be used alone or in combination of two or more.

  By adding an ion scavenger to the thermosetting resin, it is possible to adsorb ionic impurities and improve insulation reliability during moisture absorption. Examples of the ion scavenger include triazine thiol compounds and bisphenol reducing agents, such as compounds known as copper damage inhibitors to prevent copper ionization and dissolution, and zirconium and antimony bismuth magnesium aluminum compounds. And inorganic ion adsorbents.

  When forming the thermosetting resin layer 30, the thermosetting resin may be varnished. The solvent for varnishing the thermosetting resin is not particularly limited as long as it is an organic solvent, but can be determined in consideration of the volatility during film production from the boiling point. For example, a relatively low boiling point solvent such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, xylene does not cure the film during film production. This is preferable. These solvents can be used alone or in combination of two or more.

  The thickness of the thermosetting resin layer 30 is usually 5 to 200 μm, preferably 7 to 150 μm, and more preferably 10 to 100 μm. If the thickness is less than 5 μm, it becomes difficult to secure a sufficient adhesive force with the wafer, or the convex electrodes of the circuit board cannot be filled. On the other hand, when it is thicker than 200 μm, it is uneconomical, and it tends not to meet the demand for downsizing of semiconductor devices, and there is no advantage in characteristics.

  The main surface shape (planar shape) of the thermosetting resin layer 30 is preferably circular, substantially circular, or a semiconductor wafer shape.

  The thermosetting resin layer 30 also has a visible light parallel transmittance of 15 to 100% when uncured, preferably 18 to 100%, and more preferably 25 to 100%. If the visible light parallel transmittance is less than 15%, the alignment mark cannot be identified by a flip chip bonder described later, and the alignment operation between the chip and the substrate becomes difficult.

It is preferable that the thermosetting resin layer 30 can suppress the influence of the expansion | swelling by the temperature change after connecting a chip | tip and a circuit board, or heating moisture absorption. The linear expansion coefficient at 40 to 100 ° C. after curing is preferably 60 × 10 ⁻⁶ / ° C. or less, more preferably 55 × 10 ⁻⁶ / ° C. or less, and 50 × 10 ⁻⁶ / ° C. or less. More preferably it is. This is to achieve high connection reliability. When the linear expansion coefficient after curing exceeds 60 × 10 ⁻⁶ / ° C., the temperature change after mounting and expansion due to heat absorption between the chip and the circuit board wiring. Tend to be unable to maintain the electrical connection.

  As the pressure-sensitive adhesive layer 12, one having adhesive strength at room temperature and having adhesiveness to the thermosetting resin layer 30 is preferable. As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 12, for example, an acrylic resin, various synthetic rubbers, natural rubber, polyimide resin, or the like can be used. As the pressure-sensitive adhesive, those that are cured by high energy rays such as ultraviolet rays and radiation or heat (that is, the pressure-sensitive adhesive force can be reduced) are more preferable.

  As the pressure-sensitive adhesive which is cured by high energy rays (or ultraviolet rays), those whose adhesive strength is reduced by irradiation with high energy rays (or ultraviolet rays) are particularly preferable. In the case of curing using an energy beam, it is preferable to contain an energy beam curing adhesive component.

  The shape (plan view shape) of the main surface of the pressure-sensitive adhesive layer 12 has a slightly larger area than the shape of the thermosetting resin layer 30 in plan view, and can cover the thermosetting resin layer 30. It is preferable that the shape has a peripheral portion (becomes a ring mounting portion for dicing) that does not overlap the thermosetting resin layer 30. There are circular, substantially circular, quadrangular, pentagonal, hexagonal, octagonal, and wafer shapes. However, the preferable shape is circular because of the relationship with the preferable shape (circular or wafer shape) of the thermosetting resin layer 30 described above.

  The peripheral portion of the pressure-sensitive adhesive layer 12 that does not overlap the thermosetting resin layer 30 is preferably wide enough to mount and fix the dicing ring.

  The thickness of the pressure-sensitive adhesive layer 12 is usually 1 to 100 μm, preferably 2 to 20 μm, and more preferably 3 to 10 μm. If it is thinner than 1 μm, it will be difficult to ensure sufficient adhesive strength with the thermosetting resin layer 30, and the semiconductor chip may be scattered during dicing. On the other hand, if it is thicker than 100 μm, it is not economical and there is no advantage in characteristics.

  The film adhesive 100 according to the first embodiment can be produced, for example, by the method described below. That is, first, a material obtained by dissolving the raw resin composition of the thermosetting resin layer 30 in a solvent such as an organic solvent on the second plastic layer 20 to form a varnish, a knife coat method, a roll coat method, a spray coat method. Then, coating is performed by a gravure coating method, a bar coating method, a curtain coating method, or the like, and the solvent is removed to form the thermosetting resin layer 12. Thereafter, a dicing tape 14 made of the first plastic layer 10 and the pressure-sensitive adhesive layer 12 separately produced is laminated at room temperature to 60 ° C. Thereby, on the 1st plastic layer 10, the adhesive layer 12, the thermosetting resin layer 30, and the 2nd plastic layer 20 can be obtained the film adhesive 100 laminated | stacked in this order.

  In order to produce the film adhesive 110 according to the second embodiment, a release agent is applied on the second plastic layer 20 (if the release agent contains a solvent, the solvent is removed). After forming the release layer 40, the thermosetting resin layer 30, the pressure-sensitive adhesive layer 12, and the first plastic layer 10 are formed on the release layer 40 in the same manner as described above. Thereby, the film adhesive 110 can be obtained.

  As the flip chip bonder, for example, trade name Flip Chip Bonder CB-1050 manufactured by Athlete FA Co., Ltd. can be used.

  A chip recognition device of a flip chip bonder generally includes a halogen light source having a halogen lamp, a light guide, an irradiation device, and a CCD camera.

  In a state where the thermosetting resin layer 30 and the wafer circuit surface having protruding connection terminals are attached, the flip chip bonder passes through the thermosetting resin layer 30 and passes through the circuit surface of the wafer (the chip circuit surface after dicing). It is preferable to be able to identify the alignment mark formed in (1). The alignment mark is identified by a chip recognition device mounted on the flip chip bonder.

  In the present invention, “alignment is possible” means that the alignment mark image on the chip captured using the chip recognition device of the flip chip bonder and the registered alignment mark image are registered. This means that the alignment is good and the alignment work is performed reliably.

  The parallel transmittance can be measured by an integrating sphere photoelectric photometry method using a turbidimeter manufactured by Nippon Denshoku Co., Ltd., trade name NDH2000. For example, after calibrating a PET film (Purex, total light transmittance 90.45, haze 4.47) manufactured by Teijin DuPont Films Co., Ltd. with a film thickness of 50 μm as a reference material, the PET substrate is 25 μm thick and thermosetting. A resin is applied to prepare a sample. From the measurement results, turbidity, total light transmittance, diffuse transmittance, and parallel transmittance can be obtained.

  The visible light parallel transmittance can be measured with a trade name U-3310 type spectrophotometer manufactured by Hitachi, Ltd. For example, after performing baseline correction measurement using a PET film (Purex, 555 nm, transmittance 86.03%) made by Teijin DuPont Films Co., Ltd. with a film thickness of 50 μm as a reference material, thermosetting 25 μm thick on the PET substrate A transparent resin is applied, and the transmittance in the visible light region of 400 nm to 800 nm can be measured. Since the wavelength relative intensity of the halogen light source and light guide used in the flip chip bonder is strongest at 550 nm to 600 nm, the transmittance can be compared with a transmittance of 555 nm in the present invention.

  The 90 ° peel peeling force between the pressure-sensitive adhesive layer 12 and the thermosetting resin layer 30 is preferably 10 to 50 N / m at both peeling speeds of 300 mm / min and 500 mm / min. That is, the 90 ° peel peeling force is within a range of 10 N / m to 50 N / m at a peeling speed of 300 mm / min, and is within a range of 10 N / m to 50 N / m even at 500 mm / min. preferable. The 90 ° peel peeling force is more preferably 15 to 45 N / m, and further preferably 18 to 40 N / m at both peeling speeds of 300 mm / min and 500 mm / min.

  The peel force between the thermosetting resin layer 30 and the pressure-sensitive adhesive layer 12 (dicing tape 14) is measured by a 90 ° peel peel force. A dicing tape 14 including the first plastic layer 10 and the pressure-sensitive adhesive layer 12 is laminated on the thermosetting resin layer 30 at room temperature to 60 ° C., and the pressure-sensitive adhesive layer 12 and the thermosetting are formed on the first plastic layer 10. A film adhesive 100 in which the resin layer 30 and the second plastic layer 20 are laminated in this order is obtained. Thereafter, the second plastic layer 20 is peeled off, and the film adhesive is laminated on the wafer by a laminator set at a heating temperature of 80 ° C., then a 10 mm width cut is made and a strip for tensile measurement is prepared as a sample. At this time, when UV irradiation type adhesive is used, UV irradiation is appropriately performed.

  The wafer is pressed against the stage, one end of the strip sample (dicing tape 14) is fixed to a tensile jig of a tensile measuring machine, a 90 ° peel test is performed, and the sample is peeled off from the thermosetting resin. By this measurement, the 90 ° peel strength of the thermosetting resin layer 30 and the pressure-sensitive adhesive layer 12 can be measured.

  Similarly, the adhesive force between the thermosetting resin layer 30 and the wafer is measured by a 90 ° peel strength. After laminating the thermosetting resin layer 30 on a wafer with a laminator set at a heating temperature of 80 ° C., the Kapton tape (manufactured by Nitto Denko Corporation, 10 mm width, 25 μm thickness) is applied with the adhesive surface facing the thermosetting resin layer 30. After being pasted and sufficiently adhered, a 10 mm width cut is made in the thermosetting resin layer 30 having an external shape of Kapton tape.

  One end of the laminated body of the completed thermosetting resin layer 30 and the Kapton tape is peeled off from the wafer and fixed to a tension jig of a tension measuring machine. The wafer is pressed against the stage, the strip is pulled up, a 90 ° peel test is performed, and the thermosetting resin layer 30 is peeled off from the wafer. By this measurement, the adhesive force between the thermosetting resin layer 30 and the semiconductor wafer can be measured.

  The lamination of the wafer and the film adhesive or the lamination of the wafer and the thermosetting resin layer 30 is preferably performed at a temperature at which the thermosetting resin is softened. For example, it is preferably performed while heating to 40 to 80 ° C, more preferably performed while heating to 60 to 80 ° C, and further preferably laminated while heating to 70 to 80 ° C.

  When laminating at a temperature lower than the temperature at which the thermosetting resin softens, insufficient embedding of the protruding connection terminals on the periphery of the wafer circuit surface occurs, resulting in a state where a void is involved. Thereby, peeling of the chip from the film adhesive at the time of wafer dicing, deformation of the thermosetting resin layer 30 at the time of pickup, alignment mark identification failure at the time of alignment, and lowering of connection reliability due to voids, etc. There is a tendency to cause.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.

(Film A)
25 parts by weight of phenoxy resin (manufactured by Toto Kasei Co., Ltd .: trade name FX293), 20 parts of epoxy resin (made by Japan Epoxy Resin Co., Ltd., trade name E1032H60), liquid epoxy resin (made by Japan Epoxy Resin Co., Ltd., trade name Epicoat) 828) and 15 parts of a microcapsule type latent curing agent (manufactured by Asahi Kasei Electronics Co., Ltd .: trade name HX3941HP) were dissolved in a mixed solvent of toluene and ethyl acetate. The cordierite particles (2MgO · 2Al ₂ O ₃ · 5SiO ₂ , specific gravity 2.4, linear expansion coefficient 1.5 ×, with a mean particle size of 1 μm, which was subjected to a 5 μm classification treatment to remove large particle sizes. 100 parts of 10 ⁻⁶ / ° C. and a refractive index of 1.57) were added and dispersed by stirring. And after apply | coating this dispersion liquid on a separator film (PET film) using a roll coater, it was made to dry for 10 minutes in 70 degreeC oven, and the 25-micrometer-thick insulating thermosetting resin layer was obtained on a separator film. It was.

(Film B)
25 parts by weight of phenoxy resin (manufactured by Toto Kasei Co., Ltd .: trade name ZX-1356-2), 25 parts of epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., trade name E1032H60), liquid epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd.) 10 parts of the trade name Epicoat 828) and 35 parts of the microcapsule type latent curing agent (trade name HX3941HP manufactured by Asahi Kasei Electronics Co., Ltd.) were dissolved in a mixed solvent of toluene and ethyl acetate. To this solution, cordierite particles _{(2MgO · 2Al 2 O 3 ·} 5SiO 2 having an average particle diameter of 1μm subjected to classification treatment of 5μm to remove large particle size, specific gravity 2.4, the linear expansion coefficient of 1.5 × 10 ⁻⁶ / ° C., refractive index 1.57) and 87.5 parts of core-shell type impact resistance modifier (trade name KW-4426, manufactured by Mitsubishi Rayon Co., Ltd.) were added and dispersed by stirring. And after apply | coating this dispersion liquid on a separator film (PET film) using a roll coater, it was made to dry for 10 minutes in 70 degreeC oven, and the 25-micrometer-thick insulating thermosetting resin layer was obtained on the separator. .

(Film C)
Conventionally, a film generally used as a die bonding film was produced as follows. That is, 27.5 parts by weight of an epoxy resin (product name YDCN-703, manufactured by Toto Kasei Co., Ltd.), 22.5 parts by weight of a phenol resin (product name XLC-LL, manufactured by Mitsui Chemicals, Inc.), a silane coupling agent (Japan) Unicar Co., Ltd., trade name NUC A-1160) 0.7 parts by weight, silica filler (Nippon Aerosil Co., Ltd., trade name R972, average particle size 0.016 μm) 5 parts by weight, curing accelerator (Shikoku Kasei Co., Ltd.) Product, product name 2PZ-CN) 0.25 parts by weight was added, and cyclohexanone was further added and stirred and mixed. Thereafter, the obtained mixture was kneaded for 90 minutes using a bead mill. Acrylic rubber (manufactured by Nagase ChemteX Corporation, trade name HTR-860P-3, molecular weight 800,000, Tg-7 ° C.) 100 parts by weight, curing accelerator (trade name 2PZ-CN, manufactured by Shikoku Kasei Co., Ltd.) 0.5 part by weight was added and vacuum degassed. The obtained adhesive varnish was applied onto a 38 μm-thick surface release-treated polyethylene terephthalate (manufactured by Teijin DuPont Films Ltd., Teijin Tetron Film: A-31) and dried by heating at 100 ° C. for 30 minutes. Obtained.

(Dicing tape A)
For the pressure-sensitive adhesive, an acrylic copolymer using 2-ethylhexyl acrylate and methyl methacrylate as main monomers and hydroxyethyl acrylate and acrylic acid as functional group monomers was obtained by a solution polymerization method. The synthesized acrylic copolymer had a weight average molecular weight of 400,000 and a glass transition point of -38 ° C. A pressure-sensitive adhesive solution in which 10 parts by weight of a polyfunctional isocyanate crosslinking agent (trade name Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.) is blended with 100 parts by weight of this acrylic copolymer is prepared, and a polyolefin film (thickness: 100 μm) is prepared. The coating was dried so that the thickness of the pressure-sensitive adhesive upon drying was 10 μm. Furthermore, a biaxially stretched polyester film separator (thickness 25 μm) coated with a silicone release agent was laminated on the pressure-sensitive adhesive surface. The pressure-sensitive adhesive film was allowed to stand at room temperature for 1 week and sufficiently aged.

(Dicing tape B)
For the adhesive, an acrylic copolymer using 2-ethylhexyl acrylate and methyl methacrylate as main monomers and hydroxyethyl methacrylate as a functional group monomer was obtained by a solution polymerization method. The synthesized acrylic copolymer had a weight average molecular weight of 550,000 and a glass transition point of -70 ° C. A pressure-sensitive adhesive solution containing 5 parts by weight of a polyfunctional isocyanate cross-linking agent (Sumijur N75, manufactured by Sumika Bayer Urethane Co., Ltd.) was prepared with respect to 100 parts by weight of this acrylic copolymer, and a polyolefin film (thickness: 100 μm) was prepared. The coating was dried so that the thickness of the pressure-sensitive adhesive upon drying was 10 μm. Furthermore, a biaxially stretched polyester film separator (thickness 25 μm) coated with a silicone release agent was laminated on the pressure-sensitive adhesive surface. The pressure-sensitive adhesive film was allowed to stand at room temperature for 1 week and sufficiently aged.

(Examples 1 to 4 and Comparative Examples 1 and 2)
Film A, film B, film C, dicing tape A, dicing tape B and dicing tape C were bonded in the combinations shown in Table 1 at room temperature to 60 ° C. to obtain a film adhesive. The second plastic layer was peeled off from each film adhesive, and the wafer thinned by back grinding was bonded at 80 ° C. The back grind tape was peeled from the wafer and diced to 10 mm × 10 mm square with a dicer, and then the chip was picked up with a flip chip bonder. And based on the alignment mark, the flip chip was mounted in the electrode position of the resin substrate, and the semiconductor device was produced.

The film adhesive was evaluated for the following items.
(1) Dicing Tape Peeling Force The 90 ° peel peeling force (N / m) between the dicing tape and the thermosetting resin layer was measured (peeling speed: 300 mm / min and 500 mm / min).
(2) Pickup property “Good” when the success rate of pick-up by the flip chip bonder is 90% or more, and “No” when less than 90%.
(3) Visibility: “O” if alignment by flip chip bonder is possible, “X” if alignment is impossible.

  According to the present invention, a film-like adhesive used in a semiconductor wafer dicing process and a die-bonding process, which can reliably align the chip and the substrate after picking up the chip. Can provide.

  DESCRIPTION OF SYMBOLS 10 ... 1st plastic layer, 12 ... Adhesive layer, 14 ... Dicing tape, 20 ... 2nd plastic layer, 30 ... Thermosetting resin layer, 40 ... Release layer, 100 ... Film concerning 1st embodiment 110, a film adhesive according to the second embodiment.

Claims (5)

On the first plastic layer, a pressure-sensitive adhesive layer, a thermosetting resin layer and a second plastic layer are film adhesives laminated in this order,
A film adhesive in which the area of the pressure-sensitive adhesive layer is larger than the area of the thermosetting resin layer, and the thermosetting resin layer has a visible light parallel transmittance of 15 to 100% when uncured.   The film adhesive according to claim 1, further comprising a release layer between the second plastic layer and the thermosetting resin layer.   The film form according to claim 1 or 2, wherein a 90 ° peel peeling force between the pressure-sensitive adhesive layer and the thermosetting resin layer is 50 N / m or less at both peeling speeds of 300 mm / min and 500 mm / min. adhesive.   The said thermosetting resin layer is a film adhesive as described in any one of Claims 1-3 whose thickness is 5-100 micrometers.   The said thermosetting resin layer is a film adhesive as described in any one of Claims 1-4 which consists of a polymeric resin, a curable monomer, and a latent hardener at least.

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