Low resistivity (∼10−5 Ω cm2) ohmic contacts to 6H silicon carbide fabricated using cubic silicon carbide contact layer

Abstract
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 Eg∼3.0 eV). High quality ohmic contacts were produced by metallizing and annealing a thin cap layer of 3C‐SiC (Eg∼2.3 eV) grown by chemical vapor deposition on either n‐ or p‐type 6H‐SiC. The measured specific contact resistance (rc) of the ohmic contacts to n‐type 6H‐SiC was found to be less than 1.7×10−5 and 2×10−5 Ω cm2 for contacts to p‐type 6H‐SiC.