Process research on ultrasonic vibration assisted lapping of single crystal silicon carbide

Abstract

Aimming at the problems such as low material removal rate and abrasive agglomeration when polishing single crystal silicon carbide wafers with traditional methods, this study proposed a ultrasonic vibration assisted lapping method. It studied the influence of different process parameters including speeds, abrasive concentrations, pressures and abrasive grain sizes on the lapping efficiency and lapping quality of single crystal silicon carbide wafers. The experimental results and theoretical analysis show that ultrasonic vibration effectively improves the material removal rate of single crystal silicon carbide wafer polishing. When the lapping disc speed is 50 r/min, the lapping fluid concentration is 2.5%, the pressure is 0.015 MPa and the abrasive grain size is 0.5 μm, the effect of improving the material removal rate is the most obvious, thus increased by 23.4%, 33.8%, 72.3% and 184.2% respectively. At the same time, by tracking and testing the surface roughness during the lapping process, the best time for ultrasonic vibration-assisted grinding of abrasives with different particle sizes was determined.

Keywords

• ultrasonic vibration
• silicon carbide
• polishing
• material removal rate