Facet-dependent electrical conductivity properties of a 4H-SiC wafer

Intrinsic {0001} 4H-SiC wafer cut to expose {101&cmb.macr;0} and {12&cmb.macr;10} side faces allows for conductivity measurements on different crystal surfaces. The wafer has a band gap of 3.20 eV. Its {0001} face gives a strong emission band at 384 nm, but the {101&cmb.macr;0} face is barely emissive. The {0001} face is also highly electrically conductive. The {101&cmb.macr;0} and {12&cmb.macr;10} faces show similar but comparatively less conductivity than the {0001} face. Clean current-rectifying I - V curves are obtained for the {0001}/{101&cmb.macr;0} facet combination, so novel transistors can be fabricated using the electrical facet effect. Moreover, the SiC wafer displays clear photoconductivity properties. Electrical conductivity of a 4H-SiC wafer is facet-dependent with its {0001} face being much more conductive than its {101&cmb.macr;0} face, and it presents a perfect current rectification effect.