Wet-etch process and composition
AssigneeAmoco Corporation
InventorsDouglas E. Fjare, Allyson J. Beuhler, Cynthia A. Navar
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Abstract
A wet-etch composition for polyamic acids and partially cured polyamic acids comprising an aqueous solution having a major portion of water, a substituted hydrocarbon solvent and a non-ionic base that is strong enough to deprotonate the polyamic acid or a partially cured polyamic acid in a weight ratio of 0.1-49:49-0.1, with the proviso that the composition contains less than 1.0 percent ionic base. The present invention further provides a process for wet-etching polyamic acids or partially cured polyamic acids.
Claims10
A wet-etch composition for selectively etching a polyamic acid of a partially cured polyamic acid comprising an aqueous solution comprising at least 50 weight percent of the total composition of water, a substituted hydrocarbon solvent, and an alkylamine wherein the weight ratio of the substituted hydrocarbon solvent to the alkylamine is about 0.1-49:49-0.1, weight the proviso that the composition contains less than 1.0 weight percent of the total composition ionic base.
Dependencies are inferred from the claim text.