[25a-E104-1~10] 8.2 Plasma deposition of thin film, plasma etching and surface treatment

△ [25a-E104-4] Etching characteristics of gallium nitride for cyclic etching at high temperatures

〇Rikyu Minami¹, Shohei Nakamura^1,2, Atsushi Tanide², Kenji Ishikawa¹, Takayoshi Tsutsumi¹, Hiroki Kondo¹, Makoto Sekine¹, Masaru Hori¹ (1.Nagoya Univ., 2.SCREEN Holdings Co., Ltd.)

Keywords:gallium nitride, plasma etching, Atomic layer etching

Atomic layer etching is effective for controlling nanoscale etching depth and suppressing plasma irradiation damage in the production of gallium nitride (GaN) power devices. Since the vapor pressure of the nitrogen-based reaction product is higher at room temperature than that of the Ga-based reaction product, preferential desorption of nitrogen occurs. At high temperatures, the difference in vapor pressure is reduced and the preferential desorption of nitrogen is suppressed. In this study, alternating irradiation of Ar plasma and Cl radicals was performed at high temperature, and the time course of GaN film thickness was analyzed in real time using in-situ spectroscopic ellipsometry (in-situ SE).