ELECTROCHEMICAL STUDIES ON ETCHING OF MICRO-ELECTROMECHANICAL SYSTEMS (MEMS) MATERIALS IN TETRAMETHYL AMMONIUM HYDROXIDE (TMAH) SOLUTIONS: A REVIEW

摘要

This paper reviews the state-of-knowledge on etching of MEMS materials like silicon and aluminum interconnects in TMAH solutions. An analysis of the published literature shows that silicon structures having silicon oxide and or silicon nitride mask layer along with aluminum interconnect used in MEMS fabrication can be selectively and anisotropically etched in TMAH solutions by doping the TMAH solution with silicon. Currently studies are progressing with different grades of aluminum to eventually develop a better understanding of the reasons for material selectivity.