Photoelectrochemical Etching Process of 6H-SiC Wafers Using HF-Based Solution and H_2O_2 Solution as Electrolytes

摘要

In this paper a photoelectrochemical (PEC) etching process for the (6H, 4H) - SiC wafers is described. The wet etching process was made using either the HF-based solution or H_2O_2 solution. The etching characteristics of the two methods were compared. The etching rate was shown to significantly dependent on the wavelength of the UV light and resulted in different etching characteristics for (4H, 6H) - SiC wafer. The root mean square (RMS) roughness of the PEC etched surface was about 27 A. An attempt was made to employ a photoresist as a mask for patterning.