LOW-RESISTIVITY (SIMILAR-TO-10(-5)OMEGA-CM2) OHMIC CONTACTS TO 6H SILICON-CARBIDE FABRICATED USING CUBIC SILICON-CARBIDE CONTACT LAYER

Silicon carbide is a wide band-gap semiconductor material which exists in more than 170 polytypes. In this work, heteropolytype epitaxy was used to decrease the specific contact resistance of ohmic contacts to the 6H-SiC polytype (band gap E(g) approximately 3.0 eV). High quality ohmic contacts were produced by metallizing and annealing a thin cap layer of 3C-SiC (E(g) approximately 2.3 eV) grown by chemical vapor deposition on either n- or p-type 6H-SiC. The measured specific contact resistance (r(c)) of the ohmic contacts to n-type 6H-SiC was found to be less than 1.7 x 10(-5) and 2 x 10(-5) OMEGA cm2 for contacts to p-type 6H-SiC.