Al+ implanted vertical 4H-SiC p-i-n diodes: experimental and simulated forward current-voltage characteristics

The temperature dependence of the forward and reverse current voltage characteristics of circular Al+ implanted 4H-SiC p-i-n vertical diodes of various diameters, post implantation annealed at 1950 °C/5 min, have been used to obtain the thermal activation energies of the defects responsible of the generation and the recombination currents, as well as the area and the periphery current component of the current voltage characteristics. The former have values compatible with those of the traps associated to the carbon vacancy defect in 4H-SiC. The hypothesis that only these traps may justify the trend of the current voltage characteristics of the studied diodes has been tested by simulations in a Synopsys Sentaurus TCAD suite.