A study on the removal method of Si residue during Si wet etching

In this paper, problems that can occur during the poly-Si wet etch in the semiconductor manufacturing process and methods to solve these problems were introduced. In fact, when Poly-Si is etched in semiconductor process despite the over etching, etching is not clear and residue is left behind which affects huge yield drop. The reasons why Si residue is generated can be largely divided into two categories. One is low wettability by hydrophobic Si surface. The other one is local residue due to insoluble H2 Bubbles that are generated during the wet etching. This paper will explain experiments and results to solve the two problems.