High-dose Al-implanted 4H-SiC p(+)-n-n(+) junctions

p(+)-n-n(+) junctions were fabricated by ion implantation with Al of low-do ped epitaxial n layers of 4H-SiC grown by chemical vapor deposition on comm ercial 4H-SiC wafers both with and without reduction of micropipe densities . It was shown that, using high levels of Al ion doping (5x10(16) cm(-2)) i n combination with rapid thermal anneal, single-crystal p(+)-4H-SiC layers can be obtained. These layers do not form barriers at the contact metal-sem iconductor interface and do not introduce additional resistance into struct ures with p(+)-n junctions. This significantly reduces the forward voltage drop across the structure in a wide range of current densities up to 10(4) A cm(-2). (C) 2000 American Institute of Physics. [S0003-6951(00)02144-6].