Process for removal of cured epoxy

Abstract

The cleaning compositions of the present invention comprise pyridine or substituted pyridines alone or in admixture with sulfoxides. Preferred compositions comprise pyridine and dimethylsulfoxide (DMSO). Any concentration of DMSO from 0-50% can be used, but preferred compositions contain 5-25% DMSO. The present invention is employed to treat integrated circuit modules enclosed in a cap or can. Following treatment the cap or can, which is sealed to the substrate by means of the cured epoxy, can be removed to allow rework. The preferred method of removing the cured epoxy from module substrates is by refluxing in the solution. The cured epoxy is totally removed and there is no attack of the Al-Cu or Sn-Pb metallurgies or chip polyimide passivation. The silicone overcoat material is not removed from behind the chips, eliminating the need to reapply the material after rework.

Dependencies are inferred from the claim text.