Ni/W/Ni ohmic contacts for both n- and p-type 4H-SiC

Abstract

In this study, we used a Ni/W/Ni-layered structure to provide low-resistive ohmic contacts with good thermal stability for both n-type and p-type 4H-SiC. As reference, we used Ni and Ni/Ti/Ni as control groups with specific contact resistivities, and we verified the thermal stability of the structures by specific contact resistivity measurements and thermal duration tests. We found that for both n-type and p-type semiconductors, Ni/W/Ni is superior in terms of thermal stability and specific contact resistivity. Using XRD, we also analyzed the components involved in ohmic contact and thermal stability tests.