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

The current–voltage ( I – V ) characteristics and contact resistivity ( ρ c ) of Ni electrodes formed on heavily Al + -implanted p-type SiC without an alloying process were investigated. A nearly ohmic I – V curve with a ρ c of 9.3 × 10 −2 Ωcm 2 was demonstrated for non-alloyed Ni electrodes by very high-dose Al + implantation (3.1 × 10 20 cm −3 ). The dependence of the experimental ρ c on net acceptor density ( N A ) can be described by a change in the contribution of direct tunneling and trap-assisted tunneling.