Formation of ohmic contacts on heavily Al⁺-implanted p-type SiC without an alloying process

Abstract

Current–voltage (I–V) characteristics and contact resistivity (ρ c) of the Ni electrodes formed on heavily Al+-implanted p-type SiC without alloying process were investigated. A nearly ohmic I–V curve with ρ c of 9.3×10–2 Ωcm2 is demonstrated for non-alloyed Ni electrodes by very high-dose Al+ implantation (3.1×1020 cm−3). The net acceptor density dependence of the experimental ρ c can be described by a change in the contribution of direct tunneling and trap-assisted tunneling.