Study on Plasma Etching of β-Sic Thin Films Prepared by Epitaxial Grown on Si-Substrates in Different Etching Gases

Plasma etching of β-SiC single crystal thin films produced via epitaxial growth on Si-substrates have been performed with different etching gases such as CF4, SF6, CF4+O2 and SF6+O2 mixtures. Experimental results indicate that when SF6+O2 mixture is used as etching gas, the etching rates of β-SiC films are higher than those of when CF4 +O2 is used as reactant gas. When SiC films are etched using SF6+O2 mixture, no dark layer which is residual SiC with a C-rich surface is formed under any gas mixing ratio used. However, there is a very slight discoloration in the sample surface when SiC is etched by using CF4+O2 mixture. which indicates that the sample surface being etched has a better smooth finish. Etching products using different etching gases are also compared discussed