JP4976481B2 - Thermosetting die bond film, dicing die bond film, and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting die bond film which can prevent the generation of a void on the boundary of die bond film and can improve the adhesion reliability of an adherend and semiconductor chip even when exposed to a high temperature for a long time. <P>SOLUTION: The thermosetting die bond film at least includes an adhesive layer to be used for fixing a semiconductor chip on an adherend, wherein the adhesive layer contains an epoxy resin and phenol resin as thermosetting resins, as well as an acrylic resin as a thermoplastic resin having a weight-average molecular weight of 100,000 or more, and wherein X/Y is 0.07-0.7 when the total weight of epoxy resin and phenol resin is X, and the weight of acrylic resin is Y, and the reduction ratio of epoxy group after undergoing an one-hour heat treatment at 175&deg;C is 60% or less relative to the amount before the heat treatment. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a thermosetting die bond film used when, for example, a semiconductor element such as a semiconductor chip is bonded and fixed onto an adherend such as a substrate or a lead frame. The present invention also relates to a dicing die bond film in which the thermosetting die bond film and the dicing film are laminated. The present invention also relates to a semiconductor device manufactured using the thermosetting die bond film or the dicing die bond film.

  Conventionally, silver paste is used for fixing a semiconductor chip to a lead frame or an electrode member in a manufacturing process of a semiconductor device. The fixing process is performed by applying a paste adhesive on a die pad or the like of the lead frame, mounting a semiconductor chip on the lead adhesive, and curing the paste adhesive layer.

  However, paste adhesives have large variations in coating amount, coating shape, etc. due to their viscosity behavior and deterioration. As a result, the thickness of the paste-like adhesive formed is not uniform, and the reliability of the fixing strength related to the semiconductor chip is poor. That is, when the application amount of the paste adhesive is insufficient, the bonding strength between the semiconductor chip and the electrode member is lowered, and the semiconductor chip is peeled off in the subsequent wire bonding process. On the other hand, when the application amount of the paste adhesive is too large, the paste adhesive is cast onto the semiconductor chip, resulting in poor characteristics, and the yield and reliability are lowered. Such a problem in the adhering process becomes particularly remarkable as the semiconductor chip becomes larger. Therefore, it is necessary to frequently control the amount of paste adhesive applied, which hinders workability and productivity.

  In this paste adhesive application step, there is a method in which the paste adhesive is separately applied to a lead frame or a formed chip. However, in this method, it is difficult to make the paste adhesive layer uniform, and a special apparatus and a long time are required for applying the paste adhesive. For this reason, a dicing film has been proposed in which a semiconductor wafer is bonded and held in a dicing process, and an adhesive layer for chip fixation necessary for a mounting process is also provided (see, for example, Patent Document 1).

  This dicing film has an adhesive layer that can be peeled off on a support substrate. After dicing the semiconductor wafer under the holding of the adhesive layer, the support substrate is stretched to bond the formed chip. They are peeled off together with the agent layer, collected individually, and fixed to an adherend such as a lead frame through the adhesive layer.

  On the other hand, in recent years, a semiconductor device in which a plurality of semiconductor chips are stacked in multiple stages has been manufactured, and the time spent for the wire bonding process for wire bonding to the semiconductor chip and the process for thermosetting the die bond film has been prolonged. Tend to. Therefore, as a result of being exposed to a high temperature for a long time, polymerization of the thermosetting resin constituting the die bond film is excessively advanced and hardened, and bubbles (voids) may grow at the boundary between the die bond film and the adherend. there were. This void causes a problem that the semiconductor chip is peeled off from the adherend and lacks in adhesion reliability.

JP-A-60-57642

  The present invention has been made in view of the above-mentioned problems, and the object thereof is to make it easy to eliminate voids even when voids are generated at the boundary between the die bond film and the adherend. Thermosetting die-bonding film, dicing die-bonding film, and semiconductor manufactured using said thermosetting die-bonding film or dicing die-bonding film capable of improving the adhesion reliability between the adherend and the semiconductor chip To provide an apparatus.

  In order to solve the conventional problems, the inventors of the present application have studied a thermosetting die-bonding film and a dicing die-bonding film in which the thermosetting die-bonding film and the dicing film are laminated. As a result, by adopting the following configuration, even when exposed to high temperatures for a long time, it prevents the growth of voids at the boundary between the die bond film and the adherend, and adheres the adherend to the semiconductor chip. The inventors have found that the reliability can be improved and have completed the present invention.

That is, the thermosetting die-bonding film according to the present invention is a thermosetting die-bonding film having at least an adhesive layer used for fixing a semiconductor chip to an adherend, and the adhesive layer is a thermosetting resin. Containing an epoxy resin and a phenol resin, and an acrylic resin having a weight average molecular weight of 100,000 or more as a thermoplastic resin, wherein the total weight of the epoxy resin and the phenol resin is X, and the weight of the acrylic resin When X is Y, X / Y is 0.07 to 0.7, and after the heat treatment at 175 ° C. for 1 hour, the reduction rate of the epoxy group based on the pre-heat treatment is 60% or less. It is characterized by.

  According to the said structure, the reduction rate of the epoxy group on the basis of before heat processing after heat-processing at 175 degreeC for 1 hour is 60% or less, progress of thermosetting reaction is suppressed, and progress of bridge | crosslinking is suppressed. It has been. Therefore, even when a void is generated at the boundary between the adhesive layer and the adherend, the void can be easily eliminated by heat and pressure during molding. As a result, it is possible to improve the adhesion reliability between the adherend and the semiconductor chip.

In addition, after the heat treatment at 175 ° C. for 1 hour, the reduction rate of the epoxy group based on the pre-heat treatment (hereinafter also simply referred to as “decrease rate”) is as shown in the following (1) to (4). Ask.
(1) The surface of a thermosetting die-bonding film before thermosetting is measured by an ATR (attenuated total reflection) method with a Fourier transform infrared spectrophotometer (FT-IR), and an aromatic ring absorption band (1497 ± 10 cm) a maximum infrared absorption intensity (A1) in ^-1), determining the ratio (B1 / A1) between the maximum infrared absorption intensity in the absorption band of the epoxy group ^{(905 ± 10cm -1) (B1} ).
(2) The measured thermosetting die-bonding film is heat-treated at 175 ° C. for 1 hour.
(3) The surface of the thermosetting die-bonding film after the heat treatment is measured by ATR method with FT-IR, and the maximum infrared absorption intensity (A2) in the absorption band (1497 ± 10 cm ⁻¹ ) of the aromatic ring, The ratio (B2 / A2) with the maximum infrared absorption intensity (B2) in the absorption band (905 ± 10 cm ⁻¹ ) of the epoxy group is determined.
(4) The reduction rate is obtained by the following formula.
(Decrease rate (%)) = (1− (B2 / A2) / (B1 / A1)) × 100

  In addition, according to the above configuration, since X / Y is 0.07 or more and the content ratio of the thermoplastic resin is a certain value or more, it can have a certain degree of elasticity after thermosetting, and the semiconductor chip is attached. Peeling from the body can be prevented. Moreover, since X / Y is 0.7 or less and the content ratio of the thermoplastic resin is a certain value or less, it becomes possible to ensure adhesive strength at high temperatures.

  Moreover, since the weight average molecular weight of the acrylic resin as a thermoplastic resin is 100,000 or more, adhesiveness and heat resistance can be kept high. The weight average molecular weight is a value measured by GPC (gel permeation chromatography) and calculated in terms of polystyrene.

  Moreover, in the said structure, it is preferable that the said acrylic resin contains the acrylic polymer containing a glycidyl group. This is because by allowing the acrylic polymer to contain a glycidyl group, crosslinking with the acrylic polymer can proceed, and the progress of the thermosetting reaction as the entire adhesive layer can be suppressed. And since progress of the thermosetting reaction as the whole adhesive bond layer can be suppressed, it becomes possible to keep the tensile storage elastic modulus of the adhesive bond layer after thermosetting high.

  Moreover, in the said structure, it is preferable that the said adhesive bond layer does not contain a thermosetting catalyst. By not including the thermosetting catalyst, the progress of the polymerization reaction of the epoxy resin can be suppressed, and the growth of voids at the boundary between the adhesive layer and the adherend can be further suppressed.

  Moreover, in the said structure, it is preferable that the tensile storage elastic modulus in 260 degreeC after heat-processing at 175 degreeC for 1 hour is 0.5 Mpa or more. This is because, by setting the tensile storage modulus at 260 ° C. after the heat treatment to 0.5 MPa or more, it is possible to make it difficult for the semiconductor chip to peel from the adherend.

  Moreover, in order to solve the above-mentioned problems, the dicing die-bonding film according to the present invention is obtained by laminating the thermosetting die-bonding film described above on a dicing film in which an adhesive layer is laminated on a substrate. It is characterized by being.

  In order to solve the above-mentioned problems, a semiconductor device according to the present invention is manufactured using the thermosetting die-bonding film or the dicing die-bonding film described above.

It is a cross-sectional schematic diagram which shows the dicing die-bonding film which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows the dicing die-bonding film which concerns on other embodiment of this invention. It is a cross-sectional schematic diagram which shows the example which mounted the semiconductor chip through the adhesive bond layer in the dicing die-bonding film shown in FIG. It is a cross-sectional schematic diagram which shows the example which mounted the semiconductor chip three-dimensionally through the adhesive bond layer in the dicing die-bonding film shown in FIG. It is a cross-sectional schematic diagram which shows the example which mounted two-dimensionally the two semiconductor chips with the adhesive bond layer via the spacer using the dicing die-bonding film shown in FIG.

(Dicing die bond film)
A dicing die-bonding film according to an embodiment of the present invention will be described below. FIG. 1 is a schematic cross-sectional view showing a dicing die-bonding film according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing another dicing die-bonding film according to another embodiment of the present invention.

  As shown in FIG. 1, the dicing die bond film 10 has a configuration in which a die bond film 3 is laminated on a dicing film 11. The dicing film 11 is configured by laminating the pressure-sensitive adhesive layer 2 on the base material 1, and the die-bonding film 3 is provided on the pressure-sensitive adhesive layer 2. Moreover, the structure which formed the die-bonding film 3 'only in the workpiece | work affixing part may be sufficient as this invention like the dicing die-bonding film 12 shown in FIG.

  The substrate 1 has ultraviolet transparency and serves as a strength matrix for the dicing die bond films 10 and 12. For example, polyolefins such as low density polyethylene, linear polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolyprolene, polybutene, polymethylpentene, ethylene-acetic acid Vinyl copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, Polyester such as polyurethane, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyetheretherketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide, polyphenylsulfur De, aramid (paper), glass, glass cloth, fluorine resin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, metal (foil), paper, and the like.

  Moreover, as a material of the base material 1, polymers, such as the crosslinked body of the said resin, are mentioned. The plastic film may be used unstretched or may be uniaxially or biaxially stretched as necessary. According to the resin sheet to which heat shrinkability is imparted by stretching treatment or the like, the adhesive area between the pressure-sensitive adhesive layer 2 and the die bond films 3 and 3 ′ is reduced by thermally shrinking the base material 1 after dicing, so that the semiconductor chip The collection of the (semiconductor element) can be facilitated.

  The surface of the substrate 1 is chemically treated by conventional surface treatments such as chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. in order to improve adhesion and retention with adjacent layers. Alternatively, a physical treatment or a coating treatment with a primer (for example, an adhesive substance described later) can be performed. The base material 1 can be used by appropriately selecting the same kind or different kinds, and a blend of several kinds can be used as necessary.

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

  It does not restrict | limit especially as an adhesive used for formation of the adhesive layer 2, For example, common pressure sensitive adhesives, such as an acrylic adhesive and a rubber adhesive, can be used. The pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive based on an acrylic polymer from the standpoint of cleanability with an organic solvent such as ultrapure water or alcohol for electronic components that are difficult to contaminate semiconductor wafers and glass. Is preferred.

  Examples of the acrylic polymer include (meth) acrylic acid alkyl esters (for example, 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, hexadecyl ester , Octadecyl esters, eicosyl esters, etc., alkyl groups having 1 to 30 carbon atoms, especially 4 to 18 carbon linear or branched alkyl esters, etc.) and Meth) acrylic acid cycloalkyl esters (e.g., cyclopentyl ester, acrylic polymers such as one or more was used as a monomer component of the cyclohexyl ester etc.). In addition, (meth) acrylic acid ester means acrylic acid ester and / or methacrylic acid ester, and (meth) of the present invention has the same meaning.

  The acrylic polymer contains units corresponding to other monomer components copolymerizable with the (meth) acrylic acid alkyl ester or cycloalkyl ester, if necessary, for the purpose of modifying cohesive force, heat resistance and the like. You may go out. Examples of such monomer components include, for example, 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; maleic anhydride Acid anhydride monomers such as itaconic anhydride; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate Hydroxyl group-containing monomers such as 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; Styrene Contains sulfonic acid groups such as phonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalenesulfonic acid Monomers; Phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; acrylamide, acrylonitrile and the like. One or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers used is preferably 40% by weight or less based on the total monomer components.

  Furthermore, since the acrylic polymer is crosslinked, a polyfunctional monomer or the like can be included as a monomer component for copolymerization, if necessary. Examples of such polyfunctional monomers include 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) An acrylate etc. are mentioned. These polyfunctional monomers can also be used alone or in combination of two or more. The amount of the polyfunctional monomer used is preferably 30% by weight or less of the total monomer components from the viewpoint of adhesive properties and the like.

  The acrylic polymer can be obtained by subjecting a single monomer or a mixture of two or more monomers to polymerization. The polymerization can be performed by any method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization and the like. From the viewpoint of preventing contamination of a clean adherend, the content of the low molecular weight substance is preferably small. From this point, the number average molecular weight of the acrylic polymer is preferably 300,000 or more, more preferably about 400,000 to 3,000,000.

  In addition, an external cross-linking agent can be appropriately employed for the pressure-sensitive adhesive in order to increase the number average molecular weight of an acrylic polymer as a base polymer. Specific examples of the external crosslinking method include a method of adding a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, a melamine crosslinking agent, and reacting them. When using an external cross-linking agent, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked and further depending on the intended use as an adhesive. Generally, it is preferable to add about 5 parts by weight or less, and further 0.1 to 5 parts by weight with respect to 100 parts by weight of the base polymer. Furthermore, you may use additives, such as conventionally well-known various tackifier and anti-aging agent, other than the said component as needed to an adhesive.

  The pressure-sensitive adhesive layer 2 can be formed of a radiation curable pressure-sensitive adhesive. The radiation curable pressure-sensitive adhesive can increase the degree of cross-linking by irradiation with radiation such as ultraviolet rays, and can easily reduce its adhesive strength, and a portion 2a corresponding to the work pasting portion of the pressure-sensitive adhesive layer 2 shown in FIG. The difference in adhesive strength with the other part 2b can be provided by irradiating only with radiation.

  Further, by curing the radiation curable pressure-sensitive adhesive layer 2 in accordance with the die bond film 3 ′ shown in FIG. 2, the portion 2 a having a significantly reduced adhesive force can be easily formed. Since the die bond film 3 ′ is attached to the portion 2 a that has been cured and has reduced adhesive strength, the interface between the portion 2 a and the die bond film 3 ′ of the pressure-sensitive adhesive layer 2 has a property of being easily peeled off during pick-up. On the other hand, the portion not irradiated with radiation has a sufficient adhesive force, and forms the portion 2b.

  As described above, in the pressure-sensitive adhesive layer 2 of the dicing die-bonding film 10 shown in FIG. 1, the portion 2b formed of the uncured radiation-curable pressure-sensitive adhesive sticks to the die-bonding film 3 and is used when dicing. A holding force can be secured. In this way, the radiation curable pressure-sensitive adhesive can support the die bond film 3 for fixing a chip-like work (semiconductor chip or the like) to an adherend such as a substrate with a good balance of adhesion and peeling. In the pressure-sensitive adhesive layer 2 of the dicing film 11 shown in FIG. 2, the portion 2b can fix the wafer ring.

  As the radiation-curable pressure-sensitive adhesive, those having a radiation-curable functional group such as a carbon-carbon double bond and exhibiting adhesiveness can be used without particular limitation. As the radiation curable pressure sensitive adhesive, for example, an addition type radiation curable pressure sensitive adhesive in which a radiation curable monomer component or an oligomer component is blended with a general pressure sensitive pressure sensitive adhesive such as an acrylic pressure sensitive adhesive or a rubber pressure sensitive adhesive. An agent can be illustrated.

  Examples of the radiation curable monomer component to be blended include urethane oligomer, urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol. Examples include stall tetra (meth) acrylate, dipentaerystol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, and the like. Examples of the radiation curable oligomer component include various oligomers such as urethane, polyether, polyester, polycarbonate, and polybutadiene, and those having a molecular weight in the range of about 100 to 30,000 are suitable. The compounding amount of the radiation-curable monomer component or oligomer component can be appropriately determined in accordance with the type of the pressure-sensitive adhesive layer, and the amount capable of reducing the adhesive strength of the pressure-sensitive adhesive layer. Generally, the amount is, for example, about 5 to 500 parts by weight, preferably about 40 to 150 parts by weight with respect to 100 parts by weight of the base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

  In addition to the additive-type radiation curable adhesive described above, the radiation curable pressure-sensitive adhesive has a carbon-carbon double bond in the polymer side chain or main chain or at the main chain terminal as a base polymer. Intrinsic radiation curable pressure sensitive adhesives using Intrinsic radiation curable adhesives do not need to contain oligomer components, which are low molecular components, or do not contain many, so they are stable without the oligomer components moving through the adhesive over time. It is preferable because an adhesive layer having a layered structure can be formed.

  As the base polymer having a carbon-carbon double bond, those having a carbon-carbon double bond and having adhesiveness can be used without particular limitation. As such a base polymer, those having an acrylic polymer as a basic skeleton are preferable. Examples of the basic skeleton of the acrylic polymer include the acrylic polymers exemplified above.

  The method for introducing the carbon-carbon double bond into the acrylic polymer is not particularly limited, and various methods can be adopted. However, the carbon-carbon double bond can be easily introduced into the polymer side chain for easy molecular design. . For example, after a monomer having a functional group is previously copolymerized with an acrylic polymer, a compound having a functional group capable of reacting with the functional group and a carbon-carbon double bond is converted into a radiation curable carbon-carbon double bond. A method of performing condensation or addition reaction while maintaining the above.

  Examples of combinations of these functional groups include carboxylic acid groups and epoxy groups, carboxylic acid groups and aziridyl groups, hydroxyl groups and isocyanate groups, and the like. Among these combinations of functional groups, a combination of a hydroxyl group and an isocyanate group is preferable because of easy tracking of the reaction. Moreover, the functional group may be on either side of the acrylic polymer and the compound as long as the acrylic polymer having the carbon-carbon double bond is generated by a combination of these functional groups. In the preferable combination, it is preferable that 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. Further, as the acrylic polymer, those obtained by copolymerizing the above-exemplified hydroxy group-containing monomers, ether compounds of 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, or the like are used.

  As the intrinsic radiation curable pressure-sensitive adhesive, the base polymer (particularly acrylic polymer) having the carbon-carbon double bond can be used alone, but the radiation curable monomer does not deteriorate the characteristics. Components and oligomer components can also be blended. The radiation-curable oligomer component or the like is usually in the range of 30 parts by weight, preferably in the range of 0 to 10 parts by weight with respect to 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. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α′-dimethylacetophenone, 2-methyl-2-hydroxypropio Α-ketol compounds such as phenone and 1-hydroxycyclohexyl phenyl ketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1- [4- ( Acetophenone compounds such as methylthio) -phenyl] -2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether and anisoin methyl ether; ketal compounds such as benzyldimethyl ketal; 2-naphthalenesulfonyl Black Aromatic sulfonyl chloride compounds such as 1; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime; benzophenone, benzoylbenzoic acid, 3,3′-dimethyl Benzophenone compounds such as -4-methoxybenzophenone; thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2 Thioxanthone compounds such as 1,4-diethylthioxanthone and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketone; acyl phosphinoxide; acyl phosphonate. The compounding quantity of a photoinitiator is about 0.05-20 weight part with respect to 100 weight part of base polymers, such as an acryl-type polymer which comprises an adhesive.

  Examples of radiation curable pressure-sensitive adhesives include photopolymerizable compounds such as addition polymerizable compounds having two or more unsaturated bonds and alkoxysilanes having an epoxy group disclosed in JP-A-60-196956. And a rubber-based pressure-sensitive adhesive and an acrylic pressure-sensitive adhesive containing a photopolymerization initiator such as a carbonyl compound, an organic sulfur compound, a peroxide, an amine, and an onium salt-based compound.

  The radiation curable pressure-sensitive adhesive layer 2 can contain a compound that is colored by irradiation with radiation, if necessary. By including a compound to be colored in the pressure-sensitive adhesive layer 2 by irradiation with radiation, only the irradiated portion can be colored. That is, the portion 2a corresponding to the workpiece pasting portion 3a shown in FIG. 1 can be colored. Accordingly, whether or not the pressure-sensitive adhesive layer 2 has been irradiated with radiation can be immediately determined by visual observation, the workpiece pasting portion 3a can be easily recognized, and workpieces can be easily pasted together. Further, when detecting a semiconductor element by an optical sensor or the like, the detection accuracy is increased, and no malfunction occurs when the semiconductor element is picked up.

  A compound that is colored by radiation irradiation is a compound that is colorless or light-colored before radiation irradiation, but becomes colored by radiation irradiation. Preferable specific examples of such compounds include leuco dyes. As the leuco dye, conventional triphenylmethane, fluoran, phenothiazine, auramine, and spiropyran dyes are preferably used. Specifically, 3- [N- (p-tolylamino)]-7-anilinofluorane, 3- [N- (p-tolyl) -N-methylamino] -7-anilinofluorane, 3- [ N- (p-tolyl) -N-ethylamino] -7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, crystal violet lactone, 4,4 ', 4 "-trisdimethyl Examples include aminotriphenylmethanol, 4,4 ′, 4 ″ -trisdimethylaminotriphenylmethane, and the like.

  Developers preferably used together with these leuco dyes include conventionally used initial polymers of phenol formalin resins, aromatic carboxylic acid derivatives, electron acceptors such as activated clay, and further change the color tone. In some cases, various known color formers can be used in combination.

  Such a compound that is colored by irradiation with radiation may be once dissolved in an organic solvent or the like and then included in the radiation-curable adhesive, or may be finely powdered and included in the pressure-sensitive adhesive. The use ratio of this compound is 10% by weight or less, preferably 0.01 to 10% by weight, more preferably 0.5 to 5% by weight in the pressure-sensitive adhesive layer 2. When the proportion of the compound exceeds 10% by weight, the radiation applied to the pressure-sensitive adhesive layer 2 is excessively absorbed by the compound, so that the portion 2a of the pressure-sensitive adhesive layer 2 is not sufficiently cured, and is sufficiently sticky. Power may not decrease. On the other hand, in order to sufficiently color, it is preferable that the ratio of the compound is 0.01% by weight or more.

  When the pressure-sensitive adhesive layer 2 is formed of a radiation curable pressure-sensitive adhesive, a part of the pressure-sensitive adhesive layer 2 so that the pressure-sensitive adhesive force of the part 2a in the pressure-sensitive adhesive layer 2 <the pressure-sensitive adhesive force of the other part 2b. May be irradiated.

  Examples of the method for forming the portion 2a on the pressure-sensitive adhesive layer 2 include a method in which after the radiation-curable pressure-sensitive adhesive layer 2 is formed on the substrate 1, the portion 2a is partially irradiated with radiation to be cured. . The partial radiation irradiation can be performed through a photomask in which a pattern corresponding to the portion 3b other than the workpiece pasting portion 3a is formed. Moreover, the method etc. of irradiating and hardening | curing an ultraviolet-ray spotly are mentioned. The radiation curable pressure-sensitive adhesive layer 2 can be formed by transferring what is provided on the separator onto the support substrate 1. Partial radiation curing can also be performed on the radiation curable pressure-sensitive adhesive layer 2 provided on the separator.

  In the case where the pressure-sensitive adhesive layer 2 is formed of a radiation curable pressure-sensitive adhesive, all or a part of at least one side of the support substrate 1 other than the part corresponding to the workpiece pasting part 3a is shielded from light. The portion 2a with reduced adhesive strength can be formed by irradiating with radiation after forming the radiation-curable pressure-sensitive adhesive layer 2 on the substrate and curing the portion corresponding to the workpiece pasting portion 3a. . As a light shielding material, what can become a photomask on a support film can be prepared by printing, vapor deposition, or the like. According to this manufacturing method, the dicing die-bonding film 10 of the present invention can be manufactured efficiently.

  In the case where curing is inhibited by oxygen during irradiation, it is desirable to block oxygen (air) from the surface of the radiation curable pressure-sensitive adhesive layer 2 by some method. For example, a method of coating the surface of the pressure-sensitive adhesive layer 2 with a separator, a method of irradiating ultraviolet rays or the like in a nitrogen gas atmosphere, and the like can be mentioned.

  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 chipping of the chip cut surface and compatibility of fixing and holding the adhesive layer. Preferably it is 2-30 micrometers, Furthermore, 5-25 micrometers is preferable.

  The die-bonding films 3 and 3 ′ are composed of only a single adhesive layer, and contain an epoxy resin and a phenol resin as thermosetting resins, and an acrylic resin having a weight average molecular weight of 100,000 or more as a thermoplastic resin. is doing. In this embodiment, the case where the die bond films 3 and 3 ′ are composed of only a single layer of the adhesive layer will be described. However, in the present invention, the laminated structure of the die bond films 3 and 3 ′ is not particularly limited. The thing of the multilayered structure etc. which formed the adhesive bond layer in the single side | surface or both surfaces of a core material may be sufficient. Examples of the core material include a film (for example, a polyimide film, a polyester film, a polyethylene terephthalate film, a polyethylene naphthalate film, and a polycarbonate film), a resin substrate reinforced with glass fibers or plastic non-woven fibers, a silicon substrate, a glass substrate, or the like. Is mentioned.

  The epoxy resin is not particularly limited as long as it is generally used as an adhesive composition. 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, phenol novolak type, orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., bifunctional epoxy resin or polyfunctional epoxy resin, or hydantoin type, trisglycidyl isocyanurate Type or glycidylamine type epoxy resin is used. These can be used alone or in combination of two or more. Among these epoxy resins, those having an epoxy equivalent of 100 g / eq or more and 500 g / eq or less are preferable, and those having an epoxy equivalent of 150 g / eq or more and 400 g / eq or less are more preferable. It is because it is excellent in heat resistance and reaction control property. The epoxy equivalent is measured according to a potentiometric titration method defined in JIS K7236.

  The phenol resin acts as a curing agent for the epoxy resin. For example, a novolac type phenol such as a phenol novolak resin, a phenol aralkyl resin, a cresol novolak resin, a tert-butylphenol novolak resin, a phenol biphenyl resin, or a nonylphenol novolak resin. Examples thereof include resins, resol type phenol resins, polyoxystyrenes such as polyparaoxystyrene. These can be used alone or in combination of two or more. Among these phenol resins, those having a hydroxyl group equivalent of 100 g / eq or more and 500 g / eq or less are preferred, and those having 150 g / eq or more and 400 g / eq or less are more preferred. It is because it is excellent in heat resistance and reaction control property. Among the phenol resins, phenol aralkyl resins and phenol biphenyl resins are particularly preferable from the viewpoints of heat resistance and reaction control. The hydroxyl equivalent is measured according to a potentiometric titration method defined in JIS K0070.

  The mixing ratio of the epoxy resin and the phenol resin is preferably such that, for example, the hydroxyl group in the phenol resin is 0.5 to 2.0 equivalents per 1 equivalent of the epoxy group in the epoxy resin component. . More preferred 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 epoxy resin are likely to deteriorate.

  The acrylic resin has a weight average molecular weight of 100,000 or more, preferably 300,000 to 1,000,000. This is because if the weight average molecular weight is 100,000 or more, the adhesiveness and heat resistance can be kept high.

  Moreover, it is preferable that it is -30 degreeC or more and 30 degrees C or less, and, as for the glass transition point (Tg) of the said acrylic resin, it is more preferable that it is -20 degreeC or more and 15 degrees C or less. It is because the adhesiveness to a semiconductor wafer can be made sufficient by setting it as -30 degreeC or more. Moreover, it is because it can suppress a tack | tack and can improve a handleability by setting it as 30 degrees C or less. The glass transition point is obtained from the maximum value of the loss tangent (tan δ) measured by a dynamic viscoelasticity measuring device (DMA).

The acrylic resin is not particularly limited, and a polymer (copolymer) having one or more esters of acrylic acid or methacrylic acid having a linear or branched alkyl group as components. Can be mentioned. Examples of the alkyl group include a 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- Examples include an ethylhexyl group, an octyl group, an isooctyl group, a nonyl group, an isononyl group, a decyl group, an isodecyl group, an undecyl group, a lauryl group, a tridecyl group, a tetradecyl group, a stearyl group, an octadecyl group, and a dodecyl group.

  Further, the other monomer forming the polymer is not particularly limited, and examples thereof include glycidyl group-containing monomers such as glycidyl acrylate and glycidyl methacrylate, acrylic acid, methacrylic acid, carboxyethyl acrylate, and carboxypentyl. Carboxyl group-containing monomers such as acrylate, itaconic acid, maleic acid, fumaric acid or crotonic acid, acid anhydride monomers such as maleic anhydride or itaconic anhydride, 2-hydroxyethyl (meth) acrylate, (meta ) 2-hydroxypropyl acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, (meth Acry Hydroxyl group-containing monomers such as acid 12-hydroxylauryl or (4-hydroxymethylcyclohexyl) -methyl acrylate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) Sulfonic acid group-containing monomers such as acrylamide propanesulfonic acid, sulfopropyl (meth) acrylate or (meth) acryloyloxynaphthalene sulfonic acid, phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate, styrene monomers, or Acrylonitrile is mentioned.

The ratio of the acrylic polymer containing a glycidyl group contained in the acrylic resin is preferably 80 to 100 parts by weight and more preferably 90 to 100 parts by weight with respect to 100 parts by weight of the acrylic resin.

  The acrylic polymer containing a glycidyl group is preferably a copolymer of a glycidyl group-containing monomer and a monomer that does not contain a glycidyl group, and the mixing ratio thereof is, for example, considering the Tg of the copolymer It can be selected appropriately. Usually, it is preferable that 0.5 to 12.0 parts by weight of the glycidyl group-containing monomer and 88.0 to 99.5 parts by weight of the monomer not containing the glycidyl group with respect to 100 parts by weight of the raw material monomers in total. In this case, it is preferable to use ethyl (meth) acrylate and / or butyl (meth) acrylate as a monomer not containing a glycidyl group. Moreover, it is also preferable to use acrylonitrile as a monomer not containing a glycidyl group from the viewpoint of improving cohesion.

The acrylic resin preferably has an epoxy value of 0.03 to 0.5 eq / kg, and more preferably 0.05 to 0.45 eq / kg. This is because by setting the epoxy value to 0.03 eq / kg or more, the elastic modulus under high temperature conditions after thermosetting can be made sufficient. Moreover, it is because room temperature preservability can be improved by setting it as 0.5 eq / kg or less. The epoxy value is measured as follows.
(Measurement method of epoxy value)
About 3 to 4 g of the sample is precisely weighed in a 100 ml conical flask, and 10 ml of chloroform is added and dissolved. Further, 30 ml of acetic acid, 5 ml of tetraethylammonium bromide solution and 4 to 6 drops of crystal violet indicator are added, and titrated with a 0.1 mol / L perchloric acid acetic acid normal solution while stirring with a magnetic stirrer. A blank test is performed in the same manner. And an epoxy value is obtained by the following formula.
(Epoxy value) = ((V−B) × 0.1 × F) / (W × N)
W: g number of accurately weighed sample B: ml number of 0.1 mol / L perchloric acid acetic acid normal solution required for blank test V: 0.1 mol / L perchloric acid acetic acid normal solution required for titration of sample ml number F: 0.1 mol / L factor of perchloric acid acetic acid normal solution N: solid content (%)

The blend ratio of the acrylic resin is such that X / Y is 0.07 to 0.7, where X is the total weight of the epoxy resin and the phenol resin, and Y is the weight of the acrylic resin. The X / Y is preferably 0.07 to 0.6, and more preferably 0.07 to 0.45. It is because the tensile storage elastic modulus at 260 ° C. after thermosetting can be set to 0.5 MPa or more by setting X / Y to 0.07 or more. Moreover, it is because the adhesive force in high temperature conditions can be ensured by making said X / Y 0.7 or less.

  Moreover, a filler can be suitably mix | blended with die-bonding film 3, 3 'according to the use. The blending of the filler enables imparting conductivity, improving thermal conductivity, adjusting the elastic modulus, and the like. Examples of the filler include inorganic fillers and organic fillers, and inorganic fillers are preferable from the viewpoints of characteristics such as improvement in handleability, improvement in thermal conductivity, adjustment of melt viscosity, and imparting thixotropic properties. The inorganic filler is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, and aluminum borate whisker. , Boron nitride, crystalline silica, amorphous silica and the like. These can be used alone or in combination of two or more. From the viewpoint of improving thermal conductivity, aluminum oxide, aluminum nitride, boron nitride, crystalline silica, and amorphous silica are preferable. Further, from the viewpoint that the above properties are well balanced, crystalline silica or amorphous silica is preferable. In addition, a conductive substance (conductive filler) may be used as the inorganic filler for the purpose of imparting conductivity and improving thermal conductivity. Examples of the conductive filler include metal powder in which silver, aluminum, gold, cylinder, nickel, conductive alloy and the like are made into a spherical shape, needle shape and flake shape, metal oxide such as alumina, amorphous carbon black, graphite and the like.

The average particle size of the filler is preferably 0.005 to 10 μm, and more preferably 0.001 to 1 μm. This is because when the average particle size of the filler is 0.005 μm or more, the wettability to the adherend and the adhesiveness can be improved. Moreover, by setting it as 10 micrometers or less, while being able to make the effect of the filler added for provision of said each characteristic sufficient, heat resistance can be ensured. In addition, the average particle diameter of a filler is the value calculated | required, for example with the photometric type particle size distribution analyzer (The product made from HORIBA, apparatus name; LA-910).

  The filler content is preferably set to 0 to 80% by weight, and more preferably 0 to 70% by weight, based on 100 parts by weight of the total of the epoxy resin, phenol resin, and acrylic resin.

  In addition to the said filler, other additives can be suitably mix | blended with the die-bonding films 3 and 3 'as needed. Examples of other additives include flame retardants, silane coupling agents, ion trapping agents, and the like. Examples of the flame retardant include antimony trioxide, antimony pentoxide, brominated epoxy resin, and the like. These can be used alone or in combination of two or more. Examples of the silane coupling agent include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and the like. These compounds can be used alone or in combination of two or more. Examples of the ion trapping agent include hydrotalcites and bismuth hydroxide. These can be used alone or in combination of two or more.

  Although the thickness (in the case of a laminated body) of die-bonding films 3 and 3 'is not specifically limited, For example, it can select from the range of 1-200 micrometers, Preferably it is 5-100 micrometers, More preferably, it is 10- 80 μm.

  The die bond films 3, 3 'of the dicing die bond films 10, 12 are preferably protected by a separator (not shown). The separator has a function as a protective material for protecting the die bond films 3 and 3 ′ until they are put into practical use. Further, the separator can be used as a support base material when transferring the die bond films 3 and 3 ′ to the pressure-sensitive adhesive layer 2. The separator is peeled off when a workpiece is stuck on the die bond film 3, 3 'of the dicing die bond film. As the separator, a plastic film or paper surface-coated with a release agent such as polyethylene terephthalate (PET), polyethylene, polypropylene, a fluorine release agent, or a long-chain alkyl acrylate release agent can be used.

The die bond films 3 and 3 ′ have an epoxy group reduction rate of 60% or less after heat treatment at 175 ° C. for 1 hour, based on the pre-heat treatment. The reduction rate is preferably 55% or less, and more preferably 50% or less. Since the reduction rate is 50% or less and the progress of the thermosetting reaction is suppressed, the die-bonding films 3, 3 ′ have a certain degree of elasticity even after thermosetting, and the die-bonding films 3, 3 ′ and This is because it is possible to suppress the growth of voids at the boundary with the adherend.

  The die bond films 3 and 3 ′ preferably have a tensile storage modulus at 260 ° C. of 0.5 MPa or more after heat treatment at 175 ° C. for 1 hour, more preferably 0.6 MPa or more and 100 MPa or less. preferable. This is because, by setting the tensile storage modulus at 260 ° C. after the heat treatment to 0.5 MPa or more, the semiconductor chip 5 can be hardly peeled off from the adherend. In addition, the heating conditions at the time of heat-processing the die-bonding films 3 and 3 'will be described in detail later.

  Moreover, it is preferable that the die-bonding films 3 and 3 'do not contain a thermosetting catalyst. By not including the thermosetting catalyst, the progress of the polymerization reaction of the epoxy resin can be suppressed, and the growth of voids at the boundary between the die bond films 3, 3 'and the adherend can be further suppressed.

The dicing die bond films 10 and 12 according to the present embodiment are produced as follows, for example.
First, the base material 1 can be formed by a conventionally known film forming method. Examples of the film forming method include a calendar film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, and a dry lamination method.

  Next, after a pressure-sensitive adhesive composition solution is applied onto the substrate 1 to form a coating film, the coating film is dried under predetermined conditions (heat-crosslinked as necessary), and the pressure-sensitive adhesive layer 2 is formed. Form. It does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 80 to 150 ° C. and the drying time is 0.5 to 5 minutes. Moreover, after apply | coating an adhesive composition on a separator and forming a coating film, the coating film may be dried on the said drying conditions, and the adhesive layer 2 may be formed. Then, the adhesive layer 2 is bonded together with the separator on the base material 1. Thereby, the dicing film 11 is produced.

The die bond films 3 and 3 ′ are produced, for example, as follows.
First, an adhesive composition solution which is a material for forming the die bond films 3 and 3 ′ is prepared. As described above, the adhesive composition solution contains the adhesive composition, filler, and other various additives.

  Next, the adhesive composition solution is applied onto the base separator so as to have a predetermined thickness to form a coating film, and then the coating film is dried under predetermined conditions to form an adhesive layer. It does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 70 to 160 ° C. and the drying time is 1 to 5 minutes. Moreover, after apply | coating an adhesive composition solution on a separator and forming a coating film, you may dry an application film on the said drying conditions, and may form an adhesive bond layer. Then, an adhesive bond layer is bonded together with a separator on a base material separator.

  Subsequently, the separator is peeled off from each of the dicing film 11 and the adhesive layer, and the adhesive layer and the pressure-sensitive adhesive layer are bonded to each other so as to be a bonding surface. Bonding can be performed by, for example, pressure bonding. At this time, the lamination temperature is not particularly limited, and is preferably 30 to 50 ° C., for example, and more preferably 35 to 45 ° C. Moreover, a linear pressure is not specifically limited, For example, 0.1-20 kgf / cm is preferable and 1-10 kgf / cm is more preferable. Next, the base material separator on the adhesive layer is peeled off, and the dicing die-bonding film according to the present embodiment is obtained.

(Method for manufacturing semiconductor device)
The dicing die-bonding films 10 and 12 of the present invention are used as follows by appropriately separating the separator arbitrarily provided on the die-bonding films 3 and 3 ′. Hereinafter, a case where the dicing die-bonding film 10 is used will be described as an example with reference to FIG. FIG. 3 is a schematic cross-sectional view showing an example in which a semiconductor chip is mounted via an adhesive layer in the dicing die-bonding film shown in FIG.

  First, the semiconductor wafer 4 is pressure-bonded onto the workpiece bonding portion 3a of the die-bonding film 3 in the dicing die-bonding film 10, and this is adhered and held and fixed (bonding step). This step is performed while pressing with a pressing means such as a pressure roll. The attaching temperature at the time of mounting is not specifically limited, For example, it is preferable to exist in the range of 20-80 degreeC.

  Next, dicing of the semiconductor wafer 4 is performed. Thereby, the semiconductor wafer 4 is cut into a predetermined size and separated into individual pieces, and the semiconductor chip 5 is manufactured. Dicing is performed according to a conventional method from the circuit surface side of the semiconductor wafer 4, for example. Further, in this step, for example, a cutting method called full cut in which cutting is performed up to the dicing die bond film 10 can be adopted. It does not specifically limit as a dicing apparatus used at this process, A conventionally well-known thing can be used. Further, since the semiconductor wafer is bonded and fixed by the dicing die-bonding film 10, chip chipping and chip jumping can be suppressed, and damage to the semiconductor wafer 4 can also be suppressed.

  In order to peel off the semiconductor chip adhered and fixed to the dicing die bond film 10, the semiconductor chip 5 is picked up. The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, a method of pushing up the individual semiconductor chips 5 from the dicing die bond film 10 side with a needle and picking up the pushed-up semiconductor chips 5 with a pickup device may be mentioned.

  Here, since the pressure-sensitive adhesive layer 2 is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 2 is irradiated with ultraviolet rays. Thereby, the adhesive force with respect to the die-bonding film 3 of the adhesive layer 2 falls, and peeling of the semiconductor chip 5 becomes easy. As a result, the pickup can be performed without damaging the semiconductor chip 5. Conditions such as irradiation intensity and irradiation time at the time of ultraviolet irradiation are not particularly limited, and may be set as necessary. Moreover, the above-mentioned thing can be used as a light source used for ultraviolet irradiation.

  The picked-up semiconductor chip 5 is bonded and fixed to the adherend 6 via the die bond film 3 (die bond). Examples of the adherend 6 include a lead frame, a TAB film, a substrate, and a separately manufactured semiconductor chip. The adherend 6 may be, for example, a deformable adherend that can be easily deformed or a non-deformable adherend (such as a semiconductor wafer) that is difficult to deform.

  A conventionally well-known thing can be used as said board | substrate. As the lead frame, a metal lead frame such as a Cu lead frame or a 42 Alloy lead frame, or an organic substrate made of glass epoxy, BT (bismaleimide-triazine), polyimide, or the like can be used. However, the present invention is not limited to this, and includes a circuit board that can be used by mounting a semiconductor element and electrically connecting the semiconductor element.

  Since the die-bonding film 3 is a thermosetting type, the semiconductor chip 5 is bonded and fixed to the adherend 6 by heat curing to improve the heat resistance strength. The heating temperature can be 80 to 200 ° C, preferably 100 to 175 ° C, more preferably 100 to 140 ° C. The heating time can be 0.1 to 24 hours, preferably 0.1 to 3 hours, more preferably 0.2 to 1 hour. In addition, what the semiconductor chip 5 adhere | attached and fixed to the board | substrate etc. via the die-bonding film 3 can use for a reflow process.

  The shear bond strength of the die-bonding film 3 after thermosetting is preferably 0.2 MPa or more with respect to the adherend 6, more preferably 0.2 to 10 MPa. When the shear bond strength of the die bond film 3 is at least 0.2 MPa or more, the die bond film 3 and the semiconductor chip 5 or the adherend 6 are bonded by ultrasonic vibration or heating in the wire bonding process. Less shear deformation occurs on the adhesive surface. That is, the semiconductor element is less likely to move due to ultrasonic vibration during wire bonding, thereby preventing the success rate of wire bonding from decreasing.

  In addition, the manufacturing method of the semiconductor device which concerns on this invention performs wire bonding, without passing through the thermosetting process by heat processing of the die-bonding film 3, Furthermore, the semiconductor chip 5 is sealed with sealing resin, The said sealing resin May be aftercured. In this case, the shear adhesive force at the time of temporary fixing of the die bond film 3 is preferably 0.2 MPa or more, more preferably 0.2 to 10 MPa with respect to the adherend 6. When the shear bonding force at the time of temporarily fixing the die bond film 3 is at least 0.2 MPa or more, even if the wire bonding step is performed without passing through the heating step, the die bond film is caused by ultrasonic vibration or heating in the step. 3 is less likely to cause shear deformation at the bonding surface between the semiconductor chip 5 and the semiconductor chip 5 or the adherend 6. That is, the semiconductor element is less likely to move due to ultrasonic vibration during wire bonding, thereby preventing the success rate of wire bonding from decreasing.

  The wire bonding is a step of electrically connecting the tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 5 with a bonding wire 7 (see FIG. 3). . As the bonding wire 7, for example, a gold wire, an aluminum wire, a copper wire or the like is used. The temperature at the time of wire bonding is 80 to 250 ° C, preferably 80 to 220 ° C. The heating time is several seconds to several minutes. The connection is performed by a combination of vibration energy by ultrasonic waves and crimping energy by applying pressure while being heated so as to be within the temperature range. This step may be performed without thermosetting the die bond film 3.

  The sealing step is a step of sealing the semiconductor chip 5 with the sealing resin 8 (see FIG. 3). This step is performed to protect the semiconductor chip 5 and the bonding wire 7 mounted on the adherend 6. This step is performed by molding a sealing resin with a mold. As the sealing resin 8, for example, an epoxy resin is used. Although the heating temperature at the time of resin sealing is normally performed at 175 degreeC for 60 to 90 second, this invention is not limited to this, For example, it can cure at 165 to 185 degreeC for several minutes. Thereby, the sealing resin is cured, and the semiconductor chip 5 and the adherend 6 are fixed through the die bond film 3. That is, in the present invention, even when the post-curing step described later is not performed, the die bonding film 3 can be fixed in this step, and the number of manufacturing steps can be reduced and the semiconductor device manufacturing period can be reduced. It can contribute to shortening.

  In the post-curing step, the sealing resin 8 that is insufficiently cured in the sealing step is completely cured. Even if the die bond film 3 is not completely thermoset in the sealing step, the die bond film 3 can be completely thermoset together with the sealing resin 8 in this step. Although the heating temperature in this process changes with kinds of sealing resin, it exists in the range of 165-185 degreeC, for example, and heating time is about 0.5 to 8 hours.

  Further, as shown in FIG. 4, the dicing die-bonding film of the present invention can also be suitably used when a plurality of semiconductor chips are stacked and three-dimensionally mounted. 4 is a schematic cross-sectional view showing an example in which a semiconductor chip is three-dimensionally mounted via an adhesive layer in the dicing die-bonding film shown in FIG. In the case of the three-dimensional mounting shown in FIG. 4, first, at least one die bond film 3 cut out to be the same size as the semiconductor chip is die-bonded on the adherend 6, and then the semiconductor chip 5 is interposed via the die bond film 3. Die bonding is performed so that the wire bond surface is on the upper side. Next, the die bond film 13 is die bonded while avoiding the electrode pad portion of the semiconductor chip 5. Further, another semiconductor chip 15 is die-bonded on the die-bonding film 13 so that the wire-bonding surface is on the upper side.

  Next, thermosetting of the die bond films 3 and 13 is performed, and then a wire bonding process is performed. Thereby, each electrode pad in the semiconductor chip 5 and the other semiconductor chip 15 and the adherend 6 are electrically connected by the bonding wire 7.

  Subsequently, a sealing process for sealing the semiconductor chip 5 and the like with the sealing resin 8 is performed, and the sealing resin is cured. In addition, you may perform a postcure process after a sealing process.

  In the case of three-dimensional mounting of a semiconductor chip, the number of bonding wires 7 that connect the semiconductor chips 5 and 15 and the adherend 6 increases, so that the time spent in the wire bonding process tends to be long, It will be exposed to high temperature for a long time. However, according to the die bond films 3 and 13, it is possible to suppress the progress of the thermosetting reaction even when exposed to a high temperature for a long time.

  Moreover, as shown in FIG. 5, it is good also as three-dimensional mounting which laminated | stacked the spacer via the die-bonding film between the semiconductor chips. FIG. 5 is a schematic cross-sectional view showing an example in which two semiconductor chips are three-dimensionally mounted with an adhesive layer through a spacer using the dicing die-bonding film shown in FIG.

  In the case of the three-dimensional mounting shown in FIG. 5, first, the die bond film 3, the semiconductor chip 5, and the die bond film 21 are sequentially laminated on the adherend 6 and die bonded. Further, the spacer 9, the die bond film 21, the die bond film 3, and the semiconductor chip 5 are sequentially laminated on the die bond film 21 and die bonded.

  Next, thermosetting of the die bond films 3 and 21 is performed, and then a wire bonding process is performed as shown in FIG. Thereby, the electrode pad in the semiconductor chip 5 and the adherend 6 are electrically connected by the bonding wire 7.

  Then, the sealing process which seals the semiconductor chip 5 with the sealing resin 8 is performed, and the sealing resin is cured. Thereby, a semiconductor package is obtained. The sealing process is preferably a batch sealing method in which only the semiconductor chip 5 side is sealed on one side. Sealing is performed to protect the semiconductor chip 5 attached on the pressure-sensitive adhesive sheet, and the typical method is molding in a mold using the sealing resin 8. In that case, it is common to perform a sealing process simultaneously using the metal mold | die which consists of an upper metal mold | die and a lower metal mold | die which have a some cavity. The heating temperature at the time of resin sealing is preferably in the range of 170 to 180 ° C, for example. A post-curing step may be performed after the sealing step.

  The spacer 9 is not particularly limited, and for example, a conventionally known silicon chip or polyimide film can be used. A core material can be used as the spacer. It does not specifically limit as a core material, A conventionally well-known thing can be used. Specifically, a film (for example, a polyimide film, a polyester film, a polyethylene terephthalate film, a polyethylene naphthalate film, a polycarbonate film, etc.), a resin substrate reinforced with glass fibers or plastic non-woven fibers, a mirror silicon wafer, a silicon substrate or A glass substrate or the like can be used.

  Next, the semiconductor package is surface-mounted on a printed wiring board. Examples of the surface mounting method include reflow soldering in which solder is supplied on a printed wiring board in advance and then heated and melted with hot air or the like to perform soldering. Examples of the heating method include hot air reflow and infrared reflow. Moreover, any system of whole heating or local heating may be used. The heating temperature is preferably 230 to 280 ° C., and the heating time is preferably in the range of 1 to 360 seconds.

  Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, the materials, blending amounts, and the like described in this example are not intended to limit the gist of the present invention only to those unless otherwise limited.

Example 1
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by DIC Corporation, HP-7200H, epoxy equivalent 280)
9 parts by weight (b) phenol resin (Mitsui Chemicals, Millex XLC-4L, hydroxyl equivalent 170) 13 parts by weight (c) Acrylic ester polymer (manufactured by Nagase ChemteX Corporation, SG-80H, weight) Average molecular weight 350,000, epoxy value 0.07, Tg 11 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs Co., Ltd., SO-25R) 60 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film A having a thickness of 25 μm was produced.

(Example 2)
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., ESN-175S, epoxy equivalent 270)
15 parts by weight (b) phenol resin (Mitsui Chemicals, Millex XLC-4L, hydroxyl equivalent 170) 20 parts by weight (c) Acrylic acid ester polymer (manufactured by Nagase ChemteX Corporation, SG-80H, weight) Average molecular weight 350,000, epoxy value 0.07, Tg 11 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs Co., Ltd., SO-25R) 60 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film B having a thickness of 25 μm was produced.

Example 3
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by DIC Corporation, HP-7200H, epoxy equivalent 280)
3 parts by weight (b) phenolic resin (Mitsui Chemicals, Millex XLC-4L, hydroxyl equivalent 170) 5 parts by weight (c) Acrylic acid ester polymer (manufactured by Nagase ChemteX Corporation, SG-80H, weight) Average molecular weight 350,000, epoxy value 0.07, Tg 11 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs Co., Ltd., SO-25R) 60 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film C having a thickness of 25 μm was produced.

Example 4
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by DIC Corporation, HP-7200H, epoxy equivalent 280)
20 parts by weight (b) phenol resin (Mitsui Chemicals, Millex XLC-4L, hydroxyl equivalent 170) 35 parts by weight (c) Acrylic acid ester polymer (manufactured by Nagase ChemteX Corporation, SG-80H, weight) Average molecular weight 350,000, epoxy value 0.07, Tg 11 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs Co., Ltd., SO-25R) 60 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film D having a thickness of 25 μm was produced.

(Comparative Example 1)
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by DIC Corporation, HP-7200H, epoxy equivalent 280)
2 parts by weight (b) phenol resin (Mitsui Chemicals, Millex XLC-4L, hydroxyl equivalent 170) 3 parts by weight (c) acrylic ester polymer (Negami Kogyo Co., Ltd., Paracron W-197CM, weight) Average molecular weight 400,000, epoxy value 0, Tg18 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs Co., Ltd., SO-25R) 60 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film E having a thickness of 25 μm was produced.

(Comparative Example 2)
The following (a) to (e) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by DIC Corporation, HP-7200H, epoxy equivalent 280)
20 parts by weight (b) phenolic resin (Mitsui Chemicals Co., Ltd., Millex XLC-4L, hydroxyl group equivalent 170) 30 parts by weight (c) acrylic acid ester polymer (manufactured by Nagase ChemteX Corporation, SG-80H, weight) Average molecular weight 350,000, epoxy value 0.07, Tg 11 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs, SO-25R) 60 parts by weight (e) thermosetting catalyst (triphenyl phosphite, Hokuko) Chemical Co., Ltd.) 0.5 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film F having a thickness of 25 μm was produced.

(Comparative Example 3)
In Comparative Example 3, except that (e) thermosetting catalyst (Shikoku Kasei Co., Ltd., C11-Z) was used as the thermosetting catalyst of (e) above, and the addition amount was 2 parts by weight, In the same manner as in Comparative Example 2, a die bond film G according to this example was produced.

(Comparative Example 4)
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 23.6% by weight.
(A) Epoxy resin (manufactured by DIC Corporation, HP-7200H, epoxy equivalent 280)
35 parts by weight (b) phenolic resin (Mitsui Chemicals Co., Ltd., Millex XLC-4L, hydroxyl group equivalent 170) 40 parts by weight (c) Acrylic acid ester polymer (manufactured by Nagase ChemteX Corporation, SG-80H, weight) Average molecular weight 350,000, epoxy value 0.07, Tg 11 ° C.) 100 parts by weight (d) spherical silica (manufactured by Admatechs Co., Ltd., SO-25R) 60 parts by weight

  The adhesive composition solution was applied on a release film (release liner) made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. Thus, a die bond film H having a thickness of 25 μm was produced.

(Decrease rate)
It calculated | required as the following (1)-(4).
(1) About the die-bonding films A to H, the surface was measured by ATR method with FT-IR (Thermo Fisher Scientific Co., Ltd., Nicolet IR200), and the absorption band (1497 ± 10 cm ^{− of} aromatic ring) a maximum infrared absorption intensity (A1) in ^1), was determined the ratio of the maximum infrared absorption intensity (B1) in the absorption band of the epoxy group ^{(905 ± 10cm -1) (B1} / A1).
(2) Next, the measured die bond films A to H were heat-treated at 175 ° C. for 1 hour.
(3) The surface of the die bond films A to H after the heat treatment is measured by the ATR method with the FT-IR, and the maximum infrared absorption intensity (A2) in the absorption band of the aromatic ring and the absorption band of the epoxy group The ratio (B2 / A2) to the maximum infrared absorption intensity (B2) was determined.
(4) The reduction rate was calculated | required about die-bonding film AH according to the following formula, respectively.
(Decrease rate (%)) = (1− (B2 / A2) / (B1 / A1)) × 100
The results are shown in Table 1.

(Measurement of tensile storage modulus at 260 ° C after heat treatment)
The die bond films A to H were heat-treated at 175 ° C. for 1 hour. Then, it cut | disconnected so that it might become a strip-shaped measurement piece of width 10mm respectively. Next, using a fixed viscoelasticity measuring device (RSAIII, manufactured by Rheometric Scientific), the tensile storage modulus at −50 to 300 ° C. under conditions of a frequency of 1 Hz and a heating rate of 10 ° C./min. It was measured. The measured values at 260 ° C. at that time are shown in Table 1.

(Void evaluation 1)
Die bond films A to H were each attached to a 5 mm square semiconductor chip under the condition of 40 ° C., and the release liner was peeled off. Then, under the conditions of 120 ° C., 0.1 MPa, 1 second, BGA ( Ball grid array). Next, heat treatment was performed at 120 ° C. for 10 hours, and sealing was performed using a sealing resin (GE-100, manufactured by Nitto Denko Corporation). After resin sealing, the voids were observed with an ultrasonic microscope to determine the void area. The area of the void was obtained using binarization software (WinRoof ver. 5.6). A case where the void area was less than 10% with respect to the surface area of the die bond film was evaluated as ◯, and a case where it was 10% or more was evaluated as x. The results are shown in Table 1. The BGA substrate having an uneven surface is a BGA substrate having a surface roughness (centerline average roughness Ra) of 2 μm or more measured for three arbitrarily selected rows on the substrate. The surface roughness was measured with a desktop surface profiler (P-15, manufactured by KLA-Tencor).

(Void evaluation 2)
A sample was prepared in the same manner as in the void evaluation 1 except that the heat treatment condition before resin sealing was changed to 1 hour at 175 ° C., and the void area was determined. A case where the void area was less than 10% with respect to the surface area of the die bond film was evaluated as ◯, and a case where it was 10% or more was evaluated as x. The results are shown in Table 1.

(Moisture absorption reliability 1)
The die bond films A to H are each attached to a 5 mm square semiconductor chip under the condition of 40 ° C., and the release liner is peeled off, and then applied to a BGA (Ball grid array) substrate under the conditions of 120 ° C., 0.1 MPa, and 1 second. Mounted. Nine such samples were prepared for each of the die bond films A to E. Next, heat treatment was performed at 120 ° C. for 10 hours, and sealing was performed using a sealing resin (GE-100, manufactured by Nitto Denko Corporation). Next, it was left for 168 hours in an atmosphere of 85 ° C. and 60% RH. After that, it was passed through an IR reflow furnace set to maintain a temperature of 260 ° C. or higher for 10 seconds, and it was observed with an ultrasonic microscope whether peeling occurred at the interface between the semiconductor chip and the BGA substrate. As a result of observation, the probability that peeling occurred was calculated.

(Moisture absorption reliability 2)
A sample was prepared and observed in the same manner as in the moisture absorption reliability 1 except that the heat treatment condition before resin sealing was changed to 175 ° C. for 1 hour. As a result of observation, the probability that peeling occurred was calculated.

(result)
As can be seen from the results in Table 1 below, in the die bond films of Examples 1 and 2, the void area was small and the moisture absorption reliability was excellent. On the other hand, in the die bond film of Comparative Example 1, the area occupied by voids was small, but the moisture absorption reliability was poor. Moreover, in the die-bonding film of the comparative example 2 and the comparative example 3, the area which a void occupies was much and was inferior to moisture absorption reliability.

DESCRIPTION OF SYMBOLS 1 Base material 2 Adhesive layer 3, 3 'Die bond film (thermosetting type die bond film)
4 semiconductor wafer 5 semiconductor chip 6 adherend 7 bonding wire 8 sealing resin 10, 12 dicing die bond film 11 dicing film 13 die bond film (thermosetting die bond film)
15 Semiconductor Chip 21 Die Bond Film (Thermosetting Die Bond Film)

Claims (6)

A thermosetting die-bonding film having at least an adhesive layer used for fixing to an adherend of a semiconductor chip,
The adhesive layer contains an epoxy resin and a phenol resin as a thermosetting resin, and an acrylic resin having a weight average molecular weight of 100,000 or more as a thermoplastic resin,
When the total weight of the epoxy resin and the phenol resin is X and the weight of the acrylic resin is Y, X / Y is 0.07 to 0.7,
A thermosetting die-bonding film characterized in that a reduction rate of epoxy groups after heat treatment at 175 ° C. for 1 hour is 60% or less based on that before heat treatment.   The thermosetting die-bonding film according to claim 1, wherein the acrylic resin includes an acrylic polymer containing a glycidyl group.   The thermosetting die-bonding film according to claim 1, wherein the adhesive layer does not contain a thermosetting catalyst.   The thermosetting die-bonding film according to any one of claims 1 to 3, wherein a tensile storage elastic modulus at 260 ° C after heat treatment at 175 ° C for 1 hour is 0.5 MPa or more. The dicing die-bonding film, wherein the thermosetting die-bonding film according to claim 1 is laminated on a dicing film in which an adhesive layer is laminated on a substrate. A semiconductor device manufactured using the thermosetting die-bonding film according to claim 1 or the dicing die-bonding film according to claim 5.

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