JP2015151440A - Resin composition and film-like resin composition using the same, resin cured product, and method for manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which exhibits excellent flux activity and has migration resistance, and has excellent connectivity; a film-like resin composition using the same; a resin cured product; and a method for manufacturing a semiconductor device.SOLUTION: A resin composition is a resin composition containing an epoxy resin, a thermoplastic resin, a curing agent, a flux agent, and a metal hydroxide, and contains a compound having a carboxyl group as the flux agent. An amount of the metal hydroxide to be blended is preferably 0.1-5 pts.wt. with respect to 100 pts.wt. of the resin composition.

Description

  The present invention relates to a resin composition, a film-shaped resin composition using the same, a cured resin product, and a method for manufacturing a semiconductor device.

  Conventionally, in order to connect a semiconductor chip and a substrate, a wire bonding method using a fine metal wire such as a gold wire has been widely applied. On the other hand, in order to meet the demands for higher functionality, higher integration, higher speed, etc., for semiconductor devices, flip chips that form conductive protrusions called bumps on a semiconductor chip or substrate and directly connect the semiconductor chip to the substrate Connection methods (FC connection methods) are becoming widespread.

  For example, for connection between a semiconductor chip and a substrate, a COB (Chip On Board) type connection method that is actively used in BGA (Ball Grid Array), CSP (Chip Size Package), and the like also corresponds to the FC connection method. The FC connection method is also widely used in a COC (Chip On Chip) type connection method in which connection portions (bumps and wirings) are formed on semiconductor chips to connect the semiconductor chips (for example, patents). Reference 1).

  For packages that are strongly required to be further reduced in size, thickness, and functionality, a chip stack type package, POP (Package On Package), TSV (Through-Silicon Via), etc., in which the above-described connection methods are stacked and multi-staged, etc. Has also started to spread widely. Such stacking / multi-stage technology arranges semiconductor chips and the like three-dimensionally, so that the package can be made smaller than the two-dimensional arrangement technique. In addition, it is effective as a next-generation semiconductor wiring technology because it is effective for improving the performance of semiconductors, reducing noise, reducing the mounting area, and saving power.

  By the way, as a main metal used for the connection part (bump or wiring), there are solder, tin, gold, silver, copper, nickel and the like, and a conductive material including a plurality of these is also used. The metal used in the connection part may be oxidized on the surface and an oxide film may be formed, or impurities such as oxide may adhere to the surface, which may cause impurities on the connection surface of the connection part. . If such impurities remain, there is a concern that the connectivity / insulation reliability between the semiconductor chip and the substrate or between the two semiconductor chips is lowered, and the merit of employing the above-described connection method is impaired.

  In addition, as a method of suppressing the generation of these impurities, there is a method of coating a connection portion known by OSP (Organic Solderability Preservatives) treatment with an anti-oxidation film, but this anti-oxidation film has solder wettability during the connection process. May cause a decrease in connectivity and connectivity.

  Therefore, as a method for removing the above-described oxide film and impurities, a method of adding a fluxing agent to a semiconductor material has been proposed (see, for example, Patent Documents 2 to 5).

JP 2008-294382 A JP 2001-223227 A JP 2002-283098 A JP 2005-272547 A JP 2006-169407 A

  In general, metal bonding is used for connection between connection portions from the viewpoint of sufficiently ensuring connectivity and insulation reliability. Since metal bonding is a connection method using a high temperature (for example, 200 ° C. or higher), it is caused by volatile components remaining in the semiconductor sealing material and newly generated volatile components by decomposition of the components contained in the semiconductor sealing material. The semiconductor sealing material may foam. Thereby, bubbles called voids are generated, and the semiconductor sealing material is peeled off from the semiconductor chip and the substrate. In addition, when springback occurs in the void or semiconductor chip during heating and pressurization / pressure release, connection failure such as breakage of the connection portion due to tearing of the connection bump connecting the connection portions occurs.

  Also, if the semiconductor sealing material does not have sufficient flux activity (removal effect of oxide film and impurities on the metal surface), the oxide film and impurities on the metal surface cannot be removed, and a good metal-metal junction is formed. As a result, continuity cannot be ensured, resulting in poor connection.

  By the way, an organic acid such as carboxylic acid is generally used as a fluxing agent for ensuring flux activity, but materials containing organic acid often show acidity, corrode the connection bump metal, and migration occurs. There is a concern that connection failure may occur due to this.

  INDUSTRIAL APPLICABILITY The present invention provides a resin composition that exhibits good flux activity, has migration resistance, and has excellent connectivity, and a film-like resin composition, a cured resin, and a semiconductor device using the same. It aims to provide a method.

  As a result of intensive studies to solve these problems, the present inventors add a metal hydroxide to a resin composition containing an epoxy resin, a thermoplastic resin, a curing agent, and a flux agent having a carboxyl group. As a result, it was found that good migration resistance could be imparted without significantly degrading the flux activity, and that excellent connectivity could be imparted, and the present invention was completed based on such knowledge.

  That is, the present invention relates to a resin composition containing an epoxy resin, a thermoplastic resin, a curing agent, a flux agent and a metal hydroxide, and relates to a resin composition containing a compound having a carboxyl group as the flux agent.

The resin composition of the present invention can impart good migration resistance and can provide excellent connectivity without significantly deteriorating the flux activity by combining the specific components described above. As the reason for this, the present inventors consider as follows.
That is, the compound having a carboxyl group added as a fluxing agent lowers the pH of the resin composition, but the metal hydroxide functions as a neutralizing agent to raise the pH to such an extent that migration can be suppressed. Therefore, good migration resistance can be imparted without significantly impairing the flux activity. Usually, when a neutralizing agent is added, while the pH can be raised, the flux activity of a compound having a carboxyl group is significantly reduced. The reason why the metal hydroxide does not greatly affect the flux activity is not clear, but by using the present invention, it is possible to achieve both conflicting flux activity and migration resistance. Moreover, the present inventors consider as follows as a reason which can provide favorable connectivity.
When the resin composition of the present invention is connected to a semiconductor device, the surface of the metal used for the connection portion is oxidized to form an oxide film, or impurities such as oxide adhere to the surface, so that the connection portion The connection surface is poor due to the generation of impurities on the connection surface, but the resin composition of the present invention has sufficient flux activity, so that connectivity is ensured.

In general, migration is known to occur due to ionization of metal ions due to the potential difference between metal bumps and the presence of water adsorbed on the surface from the ambient atmosphere. It is thought that it is as follows.
1. Water in the ambient atmosphere is adsorbed and diffused, and water is electrolyzed by the potential difference between the bumps.
2. Metals are eluted by ions generated by electrolysis.
3. The ionized metal moves between the bumps and precipitates, causing a short circuit.

  In the migration process described above, the process of elution of the metal 2 and the movement of the ionized metal 3 between the bumps is considered to be suppressed when the pH value of the resin composition approaches 7 (neutral). Thus, migration can be suppressed by bringing the pH value of the resin composition closer to 7.

  The fluxing agent in the present invention is not particularly limited as long as it is a compound having a carboxyl group, but is preferably a compound having two carboxyl groups. Compared with a compound having one carboxyl group, a compound having two carboxyl groups is less likely to volatilize even at a high temperature during connection, and the generation of voids can be further suppressed. In addition, when a compound having two carboxyl groups is used, an increase in the viscosity of the resin composition at the time of storage and connection work can be further suppressed as compared with the case of using a compound having three or more carboxyl groups. In addition, the connectivity of the semiconductor device can be further improved.

  The metal hydroxide in the present invention is not particularly limited, but is preferably a metal hydroxide such as aluminum hydroxide, magnesium hydroxide or zinc hydroxide, or a composite metal hydroxide. Further, from the viewpoint of suppressing thickening, it is preferably magnesium hydroxide or a composite metal hydroxide, more preferably a composite hydroxide containing magnesium and zinc or magnesium and nickel, and from the viewpoint of pH increase. A composite hydroxide of magnesium and zinc is particularly preferable.

  It is preferable that the compounding quantity of the metal hydroxide in this invention is 0.1-5 mass parts with respect to 100 mass parts of said resin compositions. If it is 0.1 part by mass or more, it sufficiently functions as a neutralizing agent when added, and if it is 5 parts by mass or less, thickening is suppressed when it is formed into a film, and connectivity can be expected. It is more preferably 0.3 to 3 parts by mass, and further preferably 0.5 to 2 parts by mass.

  It is preferable that the hardening | curing agent in this invention contains an imidazole type compound at the point which is excellent in storage stability and the heat resistance of hardened | cured material.

  The resin composition in the present invention preferably further contains an inorganic filler. Thereby, the viscosity of a resin composition, the physical property of the hardened | cured material of a resin composition, etc. can be controlled with a component. Specifically, suppression of void generation at the time of connection, reduction of the moisture absorption rate of the cured product of the resin composition, and the like can be achieved.

  The resin composition in the present invention contains a thermoplastic resin, and the resin composition can be easily formed into a film by blending the thermoplastic resin into the resin composition. For this reason, it is preferable that the weight average molecular weight of a thermoplastic resin is a high molecular component of 10,000 or more. The film-like resin composition is excellent in handleability and workability, and it is possible to manufacture a semiconductor device excellent in connection reliability with good productivity. The film-like resin composition is obtained by forming the resin composition into a film shape.

In the resin composition of the present invention, the cured product of the resin composition is pulverized, and 5 g of the pulverized sample and 50 g of ion-exchanged water are put in a container and sealed, and the extract after boiling extraction at 121 ° C. and 1 atm for 20 hours is used. The pH value is preferably 5.5-7, more preferably 6-7, and even more preferably 6.3-7. Thereby, migration can be suppressed.
The resin composition or film-shaped resin composition in the present invention can be cured by heating to obtain a resin cured product. Moreover, when manufacturing a semiconductor device in which each connection portion between a semiconductor chip and a substrate or between semiconductor chips is electrically connected to each other using a resin composition or a film-like resin composition, Provided is a method for manufacturing a semiconductor device, at least a part of which is sealed with the resin composition or the film-like resin composition.
Thereby, it has excellent connection reliability by exhibiting good flux activity at the connection part, and also has migration resistance with suppressed migration that is a concern.

  The present invention can provide a resin composition that exhibits good flux activity, migration resistance, and excellent connectivity. In addition, a semiconductor device using this resin composition can be provided.

1 is a schematic cross-sectional view showing an embodiment of a semiconductor device.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

  The resin composition in the present invention is a resin composition containing an epoxy resin, a thermoplastic resin, a curing agent, a flux agent and a metal hydroxide, and contains a compound having a carboxyl group as the flux agent.

Hereinafter, each component which comprises the resin composition of this embodiment is demonstrated.
(Epoxy resin)
The epoxy resin in the present invention is not particularly limited, but those having two or more epoxy groups in the molecule can be preferably used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, naphthalene type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, phenol aralkyl type epoxy resin, biphenyl type epoxy resin, triphenylmethane type epoxy resin, di A cyclopentadiene type epoxy resin and various polyfunctional epoxy resins can be used. These can be used alone or as a mixture of two or more.

  The epoxy resin is an epoxy whose thermal weight loss rate at 250 ° C. is 5 mass% or less when the temperature at the time of connection is 250 ° C. from the viewpoint of suppressing generation of volatile components by decomposition at the time of connection at high temperature. It is preferable to use a resin. In the case of 300 ° C., it is preferable to use an epoxy resin having a thermal weight loss rate at 300 ° C. of 5% by mass or less.

  The content of the epoxy resin is, for example, 5 to 75% by mass, preferably 10 to 50% by mass, and more preferably 15 to 35% by mass, based on the total amount of the resin composition.

(Curing agent)
The curing agent in the present invention is not particularly limited, and examples thereof include imidazole compounds, phenol resin curing agents, acid anhydride curing agents, amine curing agents, and phosphine curing agents. Among them, it is desirable to use an imidazole compound that exhibits good flux activity and is excellent in storage stability and heat resistance of a cured product.

Examples of imidazole-based curing agents include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole. 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl -(1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [ 2'-ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-di Mino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2- Examples include phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins and imidazoles.
Among these, from the viewpoint of excellent curability, storage stability, and connection reliability, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimelli Tate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6 [2'-Ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine Isocyanuric acid adducts, 2-phenylimidazole isocyanuric acid adducts, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl 4- methyl-5-hydroxymethylimidazole is preferred. These can be used alone or in combination of two or more. Moreover, it is good also as a latent hardening | curing agent which encapsulated these.

  0.1-20 mass parts is preferable with respect to 100 mass parts of epoxy resins, and, as for content of an imidazole type hardening | curing agent, 0.1-10 mass parts is more preferable. If the content of the imidazole-based curing agent is 0.1 parts by mass or more, the curability tends to be improved, and if it is 20 parts by mass or less, the resin composition does not cure before the metal bond is formed. There is a tendency for poor connection to occur.

(Inorganic filler)
The resin composition in the present invention may contain an inorganic filler. Examples of the inorganic filler include glass, silica, alumina, titanium oxide, carbon black, mica, and boron nitride. Among these, silica, alumina, titanium oxide, and boron nitride are preferable, and silica, alumina, and boron nitride are more preferable. Moreover, as an inorganic filler, 1 type may be used independently and 2 or more types may be used together.

  The viscosity of the resin composition, the physical properties of the cured product of the resin composition, and the like can be controlled by the inorganic filler. Specifically, suppression of void generation at the time of connection, reduction of the moisture absorption rate of the cured product of the resin composition, and the like can be achieved.

  The shape, particle size and content of the inorganic filler are not particularly limited. Further, the inorganic filler may have its physical properties adjusted as appropriate by surface treatment.

  The content of the inorganic filler is preferably 10 to 80% by mass and more preferably 15 to 60% by mass based on the total amount of the resin composition. Furthermore, it is preferably 15 to 50% by mass from the viewpoint of the smoothness of the appearance when formed into a film and the resin composition dispersing step.

  The inorganic filler is preferably composed of an insulator. If it is made of a conductive material (for example, solder, gold, silver, copper, etc.), insulation reliability (particularly HAST resistance) may be reduced.

  Moreover, the resin composition of the present embodiment may contain a resin filler. As a result, it is possible to further suppress the generation of voids at the time of connection, reduce the moisture absorption rate of the cured product of the resin composition, and the like. As a resin filler, the filler which consists of resin, such as a polyurethane and a polyimide, is mentioned, for example.

(Thermoplastic resin)
The resin composition in the present invention contains a thermoplastic resin, and preferably contains a polymer component having a weight average molecular weight of 10,000 or more as the thermoplastic resin. A resin composition containing a polymer component having a weight average molecular weight of 10,000 or more is further excellent in heat resistance and film formability.

  Examples of the thermoplastic resin include phenoxy resin, polyimide resin, polyamide resin, polycarbodiimide resin, cyanate ester resin, acrylic resin, polyester resin, and polyethylene from the viewpoint of obtaining excellent heat resistance, film formability, and connection reliability. Resins, polyethersulfone resins, polyetherimide resins, polyvinyl acetal resins, urethane resins and acrylic rubbers are preferred. Among these, from the viewpoint of excellent heat resistance and film formability, phenoxy resin, polyimide resin, acrylic rubber, acrylic resin, cyanate ester resin and polycarbodiimide resin are more preferable, and phenoxy resin, polyimide resin, acrylic rubber and acrylic resin are more preferable. preferable. These thermoplastic resins can be used alone or as a mixture or copolymer of two or more.

The weight average molecular weight of the polymer component is 10,000 or more, preferably 20000 or more, and more preferably 30000 or more. According to such a thermoplastic resin, the heat resistance and film formability of the resin composition can be further improved.
The weight average molecular weight of the polymer component is preferably 1000000 or less, and more preferably 500000 or less. According to such a thermoplastic resin, an effect of high heat resistance is obtained.

In addition, the said weight average molecular weight shows the weight average molecular weight of polystyrene conversion measured using GPC (gel permeation chromatography, Gel Permeation Chromatography). An example of measurement conditions for the GPC method is shown below.
Device name: HCL-8320GPC, UV-8320 (product name, manufactured by Tosoh Corporation), or HPLC-8020 (product name, manufactured by Tosoh Corporation)
Column: TSKgel superMultipore HZ-M × 2, or 2pieces of GMHXL + 1 piece of G-2000XL
Detector: RI or UV detector Column temperature: 25-40 ° C
Eluent: Select a solvent in which the polymer component dissolves. For example, THF (tetrahydrofuran), DMF (N, N-dimethylformamide), DMA (N, N-dimethylacetamide), NMP (N-methylpyrrolidone), toluene. In addition, when selecting the solvent which has polarity, the density | concentration of phosphoric acid is 0.05-0.1 mol / L (usually 0.06 mol / L), and the density | concentration of LiBr is 0.5-1.0 mol / L ( Usually, it may be adjusted to 0.63 mol / L).
Flow rate: 0.30 to 1.5 mL / min Standard substance: Polystyrene

  When the resin composition contains a thermoplastic resin, the ratio (mass ratio) of the epoxy resin content to the thermoplastic resin content is preferably 0.01 to 5, and preferably 0.05 to 3. Is more preferable, and it is still more preferable that it is 0.1-2. By setting the mass ratio to 0.01 or more, better curability and adhesive strength can be obtained, and by setting the mass ratio to 5 or less, better film formability can be obtained.

(Flux agent)
The fluxing agent in the present invention is not particularly limited as long as it is a compound having a carboxyl group, but is preferably a compound having two carboxyl groups. Compared with a compound having one carboxyl group, a compound having two carboxyl groups is less likely to volatilize even at a high temperature during connection, and the generation of voids can be further suppressed. In addition, when a compound having two carboxyl groups is used, an increase in the viscosity of the resin composition at the time of storage and connection work can be further suppressed as compared with the case of using a compound having three or more carboxyl groups. In addition, the connectivity of the semiconductor device can be further improved.

  Examples of the fluxing agent include an electron donating group at the 2-position of a dicarboxylic acid selected from succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid and dodecanedioic acid. Two substituted compounds can be used.

  Examples of the flux compound include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, and dodecanedioic acid having 3 electron donating groups at the 3-position. One substituted compound can also be used.

  The melting point of the flux compound is preferably 150 ° C. or lower, more preferably 140 ° C. or lower, and further preferably 130 ° C. or lower. Such a flux compound is likely to exhibit sufficient flux activity before the curing reaction between the epoxy resin and the curing agent occurs. Therefore, according to the resin composition (semiconductor adhesive) containing such a flux compound, it is possible to realize a semiconductor device that is further excellent in connection reliability. Further, the melting point of the flux compound is preferably 25 ° C. or higher, and more preferably 50 ° C. or higher. The flux compound is preferably solid at room temperature (25 ° C.).

  The compounding quantity of the flux agent in this invention should just be the compounding quantity normally used, for example, it is preferable that it is 0.5-10 mass parts with respect to 100 mass parts of resin compositions.

  The pH value of the resin composition is preferably 5.5 or more, more preferably 6 or more, from the viewpoint of suppressing migration. The pH value is obtained by pulverizing the cured product of the resin composition, placing 5 g of the pulverized sample and 50 g of ion-exchanged water in a container and sealing it, and measuring the extracted water after boiling extraction at 121 ° C. and 1 atm for 20 hours. It is done.

  The resin composition in the present invention may further contain additives such as a curing accelerator, a silane coupling agent, a titanium coupling agent, an antioxidant, a leveling agent, and an ion trapping agent. These may be used alone or in combination of two or more. What is necessary is just to adjust about a compounding quantity so that the effect of each additive may express.

  The resin composition in the present invention can be formed into a film. An example of a method for producing a film-like resin composition using the resin composition of the present embodiment is shown below.

  First, an epoxy resin, a thermoplastic resin, a curing agent, a fluxing agent and a metal hydroxide, and an inorganic filler are added to an organic solvent, and dissolved or dispersed by stirring, mixing, kneading, etc. to prepare a resin varnish. To do. Then, after applying the resin varnish on the base film subjected to the mold release treatment using a knife coater, roll coater, applicator, etc., the organic solvent is removed by heating, thereby forming a film-like resin on the base film. A composition can be formed.

  Although the thickness of the film-like resin composition is not particularly limited, for example, it is preferably 0.5 to 1.5 times the height of the bump before connection, and more preferably 0.6 to 1.3 times. Preferably, it is 0.7 to 1.2 times.

  When the thickness of the film-shaped resin composition is 0.5 times or more the height of the bump, generation of voids due to unfilling of the resin composition can be sufficiently suppressed, and connection reliability is further improved. Can do. Further, when the thickness is 1.5 times or less, the amount of the resin composition pushed out from the chip connection region at the time of connection can be sufficiently suppressed, so that the resin composition can be sufficiently adhered to unnecessary portions. Can be prevented. If the thickness of the film-like resin composition is more than 1.5 times, bumps must be removed from many resin compositions, and poor conduction tends to occur. In addition, it is not preferable to remove a large amount of resin against weakening of the bump (miniaturization of bump diameter) due to narrow pitch and multiple pins because damage to the bump increases.

  In general, when the height of the bump is 5 to 100 μm, the thickness of the film-shaped resin composition is preferably 2.5 to 150 μm, and more preferably 3.5 to 120 μm.

  As the organic solvent used for preparing the resin varnish, those having properties capable of uniformly dissolving or dispersing each component are preferable. For example, dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, diethylene glycol dimethyl ether, Examples include toluene, benzene, xylene, methyl ethyl ketone, tetrahydrofuran, ethyl cellosolve, ethyl cellosolve acetate, butyl cellosolve, dioxane, cyclohexanone, and ethyl acetate. These organic solvents can be used alone or in combination of two or more. Stir mixing and kneading in preparing the resin varnish can be performed using, for example, a stirrer, a raking machine, a three roll, a ball mill, a bead mill, or a homodisper.

  The base film is not particularly limited as long as it has heat resistance capable of withstanding the heating conditions when the organic solvent is volatilized. Polyolefin film such as polypropylene film and polymethylpentene film, polyethylene terephthalate film, polyethylene naphthalate Examples thereof include polyester films such as films, polyimide films, and polyetherimide films. The base film is not limited to a single layer made of these films, and may be a multilayer film made of two or more materials.

  It is preferable that the drying conditions for volatilizing the organic solvent from the resin varnish applied to the base film are such that the organic solvent is sufficiently volatilized, specifically, 50 to 200 ° C. and 0.1 to 90 minutes. It is preferable to perform heating. The organic solvent is preferably removed to 1.5% by mass or less with respect to the total amount of the film-like resin composition.

  Moreover, you may form the resin composition in this invention directly on a wafer. Specifically, for example, the resin composition may be directly formed on the wafer by removing the organic solvent after spin coating the resin varnish directly on the wafer to form a film.

  The semiconductor device of this embodiment will be described below with reference to FIG. FIG. 1 is a schematic cross-sectional view showing an embodiment of a semiconductor device of the present invention. As shown in FIG. 1, a semiconductor device 100 includes a semiconductor chip 10 and a substrate (circuit wiring board) 20 that face each other, wiring 15 that is disposed on the mutually facing surfaces of the semiconductor chip 10 and the substrate 20, and a semiconductor chip. 10 and the connection bumps 30 that connect the wirings 15 of the substrate 20 to each other, and the cured resin 40 obtained by curing the resin composition filled in the gap between the semiconductor chip 10 and the substrate 20 without any gap. The semiconductor chip 10 and the substrate 20 are flip-chip connected by wiring 15 and connection bumps 30. The wiring 15 and the connection bump 30 are sealed with a cured resin 40 and are blocked from the external environment.

  The semiconductor chip 10 is not particularly limited, and an elemental semiconductor composed of the same kind of element such as silicon or germanium, or a compound semiconductor such as gallium arsenide or indium phosphide can be used.

  The substrate 20 is not particularly limited as long as it is a circuit board, and an unnecessary portion of a metal film is etched on the surface of an insulating substrate mainly composed of glass epoxy, polyimide, polyester, ceramic, epoxy, bismaleimide triazine, or the like. Circuit board having wiring (wiring pattern) 15 formed by removing, circuit board having wiring 15 formed on the surface of the insulating substrate by metal plating or the like, wiring by printing a conductive material on the surface of the insulating substrate A circuit board on which 15 is formed can be used.

  The connection parts such as the wiring 15 and the connection bumps 30 have gold, silver, copper, and solder as main components (the main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper). ), Nickel, tin, lead and the like, and may contain a plurality of metals.

  Among the above metals, gold, silver and copper are preferable, and silver and copper are more preferable from the viewpoint of providing a package with excellent electrical conductivity and thermal conductivity of the connection portion. From the viewpoint of providing a package with reduced cost, silver, copper, and solder are preferable, copper and solder are more preferable, and solder is more preferable, based on being inexpensive. If an oxide film is formed on the surface of a metal at room temperature, the productivity may decrease or the cost may increase. From the viewpoint of suppressing the formation of the oxide film, gold, silver, copper and solder are preferable, and gold, silver Solder is more preferable, and gold and silver are more preferable.

  Gold, silver, copper, solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper), tin, nickel, etc. are mainly used on the surfaces of the wiring 15 and the connection bumps 30. The metal layer as a component may be formed by plating, for example. This metal layer may be composed of only a single component or may be composed of a plurality of components.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the scope of the present invention is not limited by these.

The compounds used in each example and comparative example are as follows.
Epoxy resin 1: polyfunctional solid epoxy containing triphenolmethane skeleton (Japan Epoxy Resin Co., Ltd., trade name “EP1032H60”, hereinafter referred to as “EP1032”)
Epoxy resin 2: bisphenol F type liquid epoxy (Japan Epoxy Resin Co., Ltd., trade name “YL983U”, hereinafter referred to as “YL983U”)
Curing agent: 2-phenyl-4-methyl-5-hydroxymethylimidazole (manufactured by Shikoku Kasei Co., Ltd., trade name: 2P4MHZ-PW, hereinafter referred to as “2P4MHZ”).
Flux agent 1: Adipic acid (Tokyo Kasei Co., Ltd., melting point: about 153 ° C.)
Flux agent 2: glutaric acid (Tokyo Kasei Co., Ltd., melting point: about 98 ° C.)

  Metal hydroxide: Magnesium hydroxide / zinc hydroxide solid solution composite metal hydroxide (Tateho Chemical Co., Ltd., trade name “Echo Mug Z-10”, hereinafter referred to as “Z-10”)

Inorganic filler: Silica filler (Admatechs Co., Ltd., trade name “SE2050”, average particle size 0.5 μm, hereinafter referred to as “SE2050”)
Resin filler: Organic filler (Rohm and Haas Japan Co., Ltd., trade name “EXL-2655”, core-shell type organic fine particles, hereinafter referred to as “EXL-2655”)
Thermoplastic resin: Phenoxy resin (Toto Kasei Co., Ltd., trade name “ZX1356”, Tg: about 71 ° C., hereinafter referred to as “ZX1356”)

(Other materials)
Coupling agent: SH6040 (Silane coupling agent, Toray Dow Corning Silicone Co., Ltd., trade name, hereinafter referred to as “SH6040”)

<Preparation of resin composition>
Example 1
An epoxy resin, a curing agent, an inorganic filler, a resin filler, and methyl ethyl ketone (in which the solid content is 63% by mass) are added, and 0.8 mm diameter beads and 2.0 mm diameter beads are added in the same weight as the solid content. The mixture was stirred for 30 minutes with a planetary ball mill PM 400 manufactured by Lecce Corporation. Thereafter, a thermoplastic resin was added and stirred again for 30 minutes with a bead mill, and then the beads used for stirring were removed by filtration to obtain a resin varnish.
The obtained resin varnish was coated on a base film (trade name “Purex A70” manufactured by Teijin DuPont Films, Ltd.) with a small precision coating device (Ransui Seiki Co., Ltd.), and a clean oven (ESPEC Dried (70 ° C./10 min) to obtain a film-shaped resin composition.

(Examples 2-3, Comparative Examples 1-4)
Except having changed the resin composition of the used material as described in the following Table 1, it is the same as Example 1, and the film-like resin composition of Examples 2-3 and the film-like resin of Comparative Examples 1-4 A composition was prepared.

  Below, the evaluation method of the film-form resin composition obtained by the Example and the comparative example is shown.

<Connectivity>
The film-like resin composition produced in the example or comparative example was cut out to a predetermined size (length 8 mm × width 8 mm × thickness 0.045 mm), and a glass epoxy substrate (glass epoxy substrate: 420 μm thickness, copper wiring: 9 μm thickness) ) Affixed on top and flip-mounted a semiconductor chip with solder bumps (chip size: 7.3 mm long x 7.3 mm wide x 0.15 mm thick, bump height: copper pillar + solder meter approximately 40 μm, number of bumps 328) It was mounted with an apparatus “FCB3” (trade name, manufactured by Panasonic Corporation) (mounting conditions: pressure head temperature 350 ° C., pressure bonding time 5 seconds, pressure bonding pressure 0.5 MPa). As a result, a semiconductor device in which the glass epoxy substrate and the semiconductor chip with solder bumps were daisy chain connected as in FIG. 1 was produced.

  The connection resistance value of the obtained semiconductor device was measured using a multimeter (trade name “R6871E” manufactured by ADC Co., Ltd.) to evaluate initial conduction after mounting. When the connection resistance value is 10.0 to 13.5Ω, the connectivity is good “A”, when the connection resistance value is 13.5 to 20Ω, the connectivity is “B”, and the connection resistance value is greater than 20Ω. The case where the connection resistance value was less than 10Ω and the case of Open due to connection failure (resistance value not displayed) were all evaluated as connectivity failure “C”.

<Flux activity evaluation>
Regarding the semiconductor device manufactured by the above method, the cross section of the connection portion is observed, and the case where 90% or more of the solder is wet on the upper surface of the Cu wiring is “A” (good), and the case where the solder is less than 90%. It was evaluated as “B” (insufficient wetness).

<Evaluation of migration resistance>
The film-shaped resin composition produced by the above method is heated at 240 ° C. for 60 minutes in an air atmosphere. The obtained cured product is pulverized (Tyler 200 mesh pass), 5 g of pulverized sample and 50 g of ion-exchanged water are put in a container and sealed, and boiled and extracted at 121 ° C. and 1 atm for 20 hours. It was measured. The pH value of the extract at this time was measured, and the case where the pH value was 5.5 to 7 was evaluated as “A” (good), and the case where the pH value was less than 5.5 or more than 7 was evaluated as “B”.
These evaluation results are summarized in Table 1.

  The resin compositions of Examples 1 to 3 have good flux activity and at the same time have a pH value of 5.5 to 7.0, and therefore can suppress the occurrence of migration. Furthermore, it turns out that it is excellent in connectivity. Moreover, since Comparative Examples 1 and 2 do not contain a metal hydroxide, the pH value is less than 5.5, and there is a concern about the occurrence of migration. Since Comparative Example 3 did not contain a fluxing agent, the solder wettability was not sufficient, and the connectivity was poor. Moreover, since the comparative example 4 did not contain a metal hydroxide and a flux agent, the pH value was less than 5.5, the solder wettability was not sufficient, and the connectivity was poor.

DESCRIPTION OF SYMBOLS 10 ... Semiconductor chip, 15 ... Wiring (connection part), 20 ... Board | substrate (circuit wiring board), 30 ... Connection bump, 40 ... Resin hardened | cured material, 100 ... Semiconductor device

Claims (10)

  A resin composition comprising an epoxy resin, a thermoplastic resin, a curing agent, a fluxing agent, and a metal hydroxide, and comprising a compound having a carboxyl group as the fluxing agent.   The resin composition of Claim 1 whose compounding quantity of the said metal hydroxide is 0.1-5 mass parts with respect to 100 mass parts of said resin compositions.   The resin composition according to claim 1 or 2, wherein the compound having a carboxyl group as the fluxing agent is a compound having two carboxyl groups.   The resin composition according to any one of claims 1 to 3, wherein the curing agent contains an imidazole compound.   The resin composition according to any one of claims 1 to 4, further comprising an inorganic filler.   The resin composition according to any one of claims 1 to 5, wherein the thermoplastic resin is a polymer component having a weight average molecular weight of 10,000 or more.   The cured product of the resin composition is pulverized, 5 g of the pulverized sample and 50 g of ion-exchanged water are put in a container and sealed, and the pH value after boiling extraction at 121 ° C. and 1 atm for 20 hours is 5.5 to 7. The resin composition according to any one of claims 1 to 6.   The film-form resin composition formed by shape | molding the resin composition as described in any one of Claims 1-7 in a film form.   A cured resin obtained by curing reaction of the resin composition according to any one of claims 1 to 7 and the film-like resin composition according to claim 8.   A semiconductor device and a substrate, or a method for manufacturing a semiconductor device in which respective connection portions between semiconductor chips are electrically connected to each other, wherein at least a part of the connection portions is defined in any one of claims 1 to 7. A method for producing a semiconductor device sealed with the resin composition according to claim 8 or the film-like resin composition according to claim 8.

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