Effects of heating ramp rates on the characteristics of Al implanted 4H–SiC junctions

Abstract

The role of the heating rate in the postimplantation annealing process of SiC was investigated. Structural and electrical properties of an Al+ implanted junction in n-type 4H–SiC were studied for a 30min annealing at 1600°C in argon atmosphere and changing the heating rate between 7 and 40°C∕s. With the increasing of the heating rate the surface roughness increases, but the electrical performance of the devices improves. In particular, the faster ramp-up rate reduces the sheet resistance of the implanted layer of about 40% with respect to the slowest process and significantly reduces the leakage current of the diodes.