Abstract: Epoxy resin compositions comprising (A) an epoxy resin having an epoxy equivalent of at least 185 and possessing a structure in which two benzene rings can be directly conjugated, carbon atoms having an sp2 type atomic orbital accounting for at least 50% of all the carbon atoms, (B) a &bgr;-naphthol type phenolic resin curing agent, (C) a curing accelerator, and (D) an inorganic filler cure into products having satisfactory solder crack resistance on use of lead-free solder and improved flame retardance despite the absence of halogenated epoxy resins and antimony compounds and are thus suited for semiconductor encapsulation.

Abstract: Semiconductor encapsulating epoxy resin compositions comprising an epoxy resin, a phenolic resin curing agent, a fire retardant comprising zinc molybdate carried on spherical silica having a mean particle diameter of 0.2-20 &mgr;m and a specific surface of 1-20 m2/g, and an inorganic filler are able to provide cured products having excellent fire retardance. The compositions have good flow and curing properties and excellent reliability and do not pose a hazard to human health or the environment.

Abstract: Semiconductor encapsulating epoxy resin compositions comprising an epoxy resin, a phenolic resin curing agent, a fire retardant comprising zinc molybdate carried on spherical silica having a mean particle diameter of 0.2-20 &mgr;m and a specific surface of 1-20 m2/g, and an inorganic filler are able to provide cured products having excellent fire retardance. The compositions have good flow and curing properties and excellent reliability and do not pose a hazard to human health or the environment.

Abstract: In an epoxy resin composition comprising an epoxy resin, a curing agent, and an inorganic filler, the filler is porous silica having a specific surface area of 6-200 m2/g, a true specific gravity of 2.0-2.2, and a mean particle size of 2-50 &mgr;m. The epoxy resin composition is readily moldable, has a low moisture permeability and reliability in the cured state, and is suitable for forming a premolded hollow semiconductor package.

Abstract: In an epoxy resin composition comprising an epoxy resin, a curing agent, and an inorganic filler, the filler is porous silica having a specific surface area of 6-200 m2/g, a true specific gravity of 2.0-2.2, and a mean particle size of 2-50 &mgr;m. The epoxy resin composition is readily moldable, has a low moisture permeability and reliability in the cured state, and is suitable for forming a premolded hollow semiconductor package.

Abstract: A semiconductor encapsulating epoxy resin composition comprising (A) an epoxy resin, (B) a phenolic resin curing agent, (C) a molybdenum compound, and (D) 300-900 parts by weight per 100 parts by weight of components (A) and (B) combined of an inorganic filler contains nitrogen atoms in an amount of 1.5-20% by weight based on the weight of components (A) and (B) combined. Cured parts of the composition exhibit high-temperature capabilities and flame retardance despite the absence of halogenated epoxy resins and antimony trioxide.

Abstract: An epoxy resin composition comprising (A) a biphenyl skeleton epoxy resin, (B) a biphenyl skeleton phenolic resin as a curing agent, (C) molybdenum compound, and (D) an inorganic filler is suited for semiconductor encapsulation since it is effectively moldable and cures into a part having improved reflow crack resistance, moisture resistance, and flame retardance. It does not pose a hazard to human health or the environment.

Abstract: A semiconductor encapsulating epoxy resin composition is provided comprising (A) an epoxy resin, (B) a phenolic resin curing agent, (C) a microencapsulated flame retardant comprising a red phosphorus-base core coated with a thermoplastic resin and/or thermosetting resin, (D) a molybdenum compound, and (E) an inorganic filler. The composition and its cured product have moisture-proof reliability and high flame retardance despite the absence of halogenated epoxy resins and antimony oxide.

Abstract: An epoxy resin composition contains (A) an epoxy resin, (B) a phenolic resin curing agent, (C) a curing catalyst, and (D) an inorganic filler. The catalyst is a quaternary phosphorus compound or a quaternary phosphorus compound which has been mixed and reacted with a phenolic resin having at least two hydroxyl groups. The composition is effectively flowable, moldable and curable and thus suitable for semiconductor encapsulation.

Abstract: In an epoxy resin composition comprising an epoxy resin, a curing agent, and an inorganic filler, the filler is porous silica having a specific surface area of 6-200 m2/g, a true specific gravity of 2.0-2.2, and a mean particle size of 2-50 &mgr;m. The epoxy resin composition is readily moldable, has a low moisture permeability and reliability in the cured state, and is suitable for forming a premolded hollow semiconductor package.

Abstract: Epoxy resin compositions comprising (A) a crystalline epoxy resin, (B) a polyfunctional phenolic resin, (C) an organic phosphorus curing accelerator, (D) an aminosilane coupling agent, and (E) at least 88 wt % based on the composition of an inorganic filler are smoothly flowing, fast curing and shelf stable. Due to minimized package warp, minimized wire flow, improved adhesion, and low water absorption, the compositions enable highly reliable encapsulation of semiconductor devices, especially BGA.

Abstract: By removing a fraction of fine particles having a particle size of less than 2 &mgr;m from starting inorganic filler particles having a mean particle size of 10-50 mm and adding thereto particles having a mean particle size of 0.1-2 &mgr;m and a specific surface area of 3-10 m2/g (BET), there is obtained a particulate inorganic filler having a mean particle size of 5-40 &mgr;m. When a large amount of the inorganic filler is loaded in an epoxy resin composition, the composition maintains a low melt viscosity enough to mold and is effective for encapsulating a semiconductor device without causing die pad deformation and wire deformation. The encapsulated semiconductor device is highly reliable.

Abstract: A flame retardant epoxy resin composition suitable for semiconductor encapsulation contains (A) a crystalline epoxy resin whose 30 wt % m-cresol solution has a viscosity of lower than 80 centipoise at 25° C., (B) a curing agent having at least two phenolic hydroxyl groups, and (C) silica. The composition optionally contains (D) an organopolysiloxane, (E) an organic phosphine oxide, (F) an amide group-containing release agent, and/or (G) a silane coupling agent. The cured composition achieves flame retardance rating UL-94 V-0 without a need for flame retardants and remains stable at high temperature.

Abstract: An epoxy resin composition comprising an epoxy resin, a curing agent, an inorganic filler, and a curing accelerator is suited for semiconductor encapsulation. A specific organic phosphorus compound is used as the curing accelerator. The composition is smoothly flowing, stable during storage, effectively curable and mold releasable and can be molded and cured into products free from wire flow and voids.

Abstract: An epoxy resin composition comprising (A) a biphenyl skeleton-bearing epoxy resin, (B) a biphenyl skeleton-bearing phenolic resin as a curing agent, (C) an organosiloxane containing phenyl and organooxy groups, and (D) an inorganic filler is suited for semiconductor encapsulation since it is effectively moldable and cures into a part having improved reflow crack resistance, moisture resistance, and flame retardance. It does not pose a hazard to human health or the environment.

Abstract: An epoxy resin composition comprising an epoxy resin of a specific structure, a phenolic resin of a specific structure, and an inorganic filler is suited for semiconductor encapsulation since it is effectively moldable and cures into products having improved flame retardance, reflow crack resistance and dielectric properties.

Abstract: Epoxy resin compositions comprising (A) a polyfunctional epoxy resin, (B) a polyfunctional phenolic resin curing agent, (C) an organophosphorus curing accelerator, (D) an aminosilane coupling agent, and (E) an inorganic filler have excellent flow properties, shelf stability and curing speed and are thus suitable for semiconductor encapsulation, especially BGA encapsulation. Semiconductor devices encapsulated with the epoxy resin compositions are highly reliable.

Abstract: An epoxy resin composition comprising a crystalline epoxy resin, a phenolic resin, and an inorganic filler is improved in moldability by previously reacting phenolic hydroxyl groups on the phenolic resin with epoxy groups on the crystalline epoxy resin to form a reaction product and blending the reaction product in the composition. The composition is moldable over semiconductor devices without voids and wire flow. The encapsulated semiconductor devices thus remain reliable.

Abstract: An epoxy resin composition comprising an epoxy resin, a curing agent, and an inorganic filler has a melt viscosity of at most 150 poise at 175.degree. C. The inorganic filler has a BET specific surface area of 1.5-6 m.sup.2 /g and is such that when a 75/25 mixture of the inorganic filler and a bisphenol F type liquid epoxy resin is measured for viscosity at shear rates of 0.6/sec. and 10/sec. at a temperature of 25.+-.0.05.degree. C. by an E type viscometer, the ratio of the viscosity at 0.6/sec. to the viscosity at 10/sec. is at least 3.5/1. The amount of the inorganic filler loaded is 80-90% by weight of the composition. The composition is suitable for the encapsulation of matrix frames.

Abstract: In an epoxy resin composition comprising an epoxy resin, a curing agent, and 80-90 wt % of a particulate inorganic filler, fine particles having a particle size of less than 3 .mu.m account for 10-40 wt % of the inorganic filler, and the inorganic filler has a specific surface area of less than 2.5 m.sup.2 /g as measured by a nitrogen adsorption BET method. The inorganic filler satisfies that when a blend of a bisphenol F type liquid epoxy resin having a viscosity of 30-45 poises at 25.degree. C. as measured by Gardner-Holdt method with 75 wt % of the inorganic filler is measured for viscosity at 25.degree. C. by means of an E type viscometer, the viscosity at a shear rate of 0.6 s.sub.-1 is less than 50,000 poises and the ratio of the viscosity at a shear rate of 0.6 s.sup.-1 to the viscosity at a share rate of 10 s.sup.-1 is less than 2.5/1. The epoxy resin composition has a low melt viscosity enough to mold on semiconductor devices without die pad and wire deformation.