Epoxy resin composition

Abstract

An epoxy resin composition comprising, as main components, (a) 100 parts by weight of a polyfunctional epoxy resin which stays liquid at an ordinary temperature and has two or more glycidyl groups in the molecule thereof, (b) 3 to 80 parts by weight of a curing agent and (c) 1 to 100 parts by weight of a modified epoxy resin, is suitable as an underfill sealing agent, is capable of heat-curing in a short time with a good productivity, is capable of surely connecting a semiconductor device such as a CSP and a BGA on a wiring board without giving an adverse effect on each part disposed on the wiring board by heat-curing at a relatively low temperature, has excellent heat shock property (temperature cycling property) and impact resistance, is free from bleeding of contaminants from its cured product, and is capable of easily detaching the CSP or BGA from the wiring board in the case where a defect is found, making it possible to reuse a normal wiring board or semiconductor device.

Dependencies are inferred from the claim text.