Formation of ammonium salts and their effects to control pattern profile in the RIE process fabricating aluminum wirings and poly-silicon gates

摘要

In the RIE process fabricating aluminum wirings and poly-Si gates,it is well-known that etching characteristics are changed by the addition of N_2 to the etching gas.In this paper,we report that ammonium salts were formed by the reaction of nitrogen with hydrogen contained in the photoresist or the etching gas during the RIE process,and they had big effects on the pattern profile of aluminum wirings and poly-Si gates.