Liquid-phase epitaxial growth of heavily doped Al p-type contact layers for SiC devices and resulting ohmic contacts

In this paper we report on ohmic contacts to p-type silicon carbide with record low specific contact resistance. The contacts were formed to p(+)-SiC layers with high Al concentration grown by liquid phase epitaxy (LPE) on 2 inch 6H and 4H-SiC samples. Al atomic concentration in LPE grown layers exceeded 1x10(20) cm(-3). Ti-Al ohmic contacts with contact resistivity in 10(-6) Omegaxcm(2) range were fabricated to both p-6H-SiC and p-4H-SiC materials in reproducible manner. Developed LPE technology may substitute ion implantation technique for p(+)-contact layer formation for power SiC devices.