Fabrication of Quartz Crystal Resonator by Inductively Coupled Plasma Etching Method

Abstract

Abstract: In order to fabricate quartz crystal resonators, the step morphology was prepared on the quartz substrate by photolithography and inductively coupled plasma etching. The influences of the process parameters such as the excitation power, the bias power and the heat-conducting substance on the etching effect were studied. The surface morphology of etched pattern was observed using scanning electron microscope, and the process parameters which meet the requirements of industrial production were obtained through experiment and analysis. Finally, the vertical step morphology with a height of about 22 μm was obtained using optimized processing parameters. The characteristics of dry etching and the feasibility of dry etching for industrial production of quartz crystal resonators were demonstrated by comparing with wet etching.

Key words: quartz crystal, photolithography, inductively coupled plasma etching, processing parameter, step etching

CLC Number:

TH162

CHEN Jingbai, ZHANG Xinhai, LIU Feng. Fabrication of Quartz Crystal Resonator by Inductively Coupled Plasma Etching Method[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(9): 3395-3401.

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