ELECTROLYTIC SOLUTION FORMULATION FOR ELECTROPOLISHING PROCESS

摘要

An electrolytic solution formulation for an electropolishing process comprises at least an acid solution and an organic additive. The acid solution includes phosphoric acid or a mixture of phosphoric acid and sulfuric acid solutions, which can form a passivation layer on the surface of the metal layer. The additive comprises at least an acide group, wherein the diffusion of the organic additive is controlled in which a concentration graident is formedin the opening of the metal layer. The electropolishing rate at the top of the opening is thereby faster than that at the bottom of the opening. The organic additive is selected from a monocaboxylic acid compound, a dicarboxylic acid compound, a tricarboxylic acid compound, a heterocyclic carboxylic acid compound or a sulfonic acid compound.