Inductively coupled plasma etching of LiTaO₃ in CHF₃/Ar plasmas

Abstract

CHF₃/Ar plasma was used to etch LiTaO₃ crystal by inductively coupled plasma technology. The etched crystals under different process parameters were analyzed by surface profilometer and characterized by atomic force microscopy and scanning electron microscope. It was shown that ICP power, RIE power, and total gas flow rate had similar effects on etching rate and selectivity, while Ar/(Ar + CHF₃) gas ratio had opposite effects on etching rate and selectivity, with better etching rate and selectivity at the ratio of 0.2. Our work gives a fundamental instruction for the fabrication of LiTaO₃ based devices.

Keywords:

• LiTaO₃
• inductively coupled plasma
• etching rate
• selectivity

Additional information

Funding

This work was financially supported by the Science and Technology Department of SICHUAN Province (2020YFG0042) and the Foundation of State Key Laboratory of Electronic Thin Films and Integrated Devices (kFJJ201911).