Advantages of Creating Buffered HF at the Point-of-Use

摘要

A new way of forming buffered hydrofluoric acid (BHF) at the point-of-use (POU) offers substantial advantages compared with conventional pre-mixed BHF solutions. The new method involves co-injection of HF and ammonium hydroxide (NH_4OH) immediately prior to use. Results show better etch uniformity, lower metallic impurities, lower particle densities and no need for surfactants. These are the findings of Dr. Steven Verhaver-beke, director of research for CFM Technologies Inc. (West Chester, Pa.). Verhaverbeke presented his work at the 14th International Symposium on Contamination Control, held April 26-May 1 in Phoenix, Ariz., part of the 44th Annual Meeting of the Institute of Environmental Sciences (IES, Mt. Prospect, Ill..).