Electrical and optical characterization of intrinsic and ion-implantation induced defects in 6-hydrogen-silicon carbide and 4-hydrogen-silicon carbide

Deep level transient spectroscopy (DLTS), Hall effect, and cathodoluminescence (CL) measurements are used to characterize shallow and deep level defects in high-temperature (475 and 500°C) ion-implanted (Ar +, Cr+, Mg+, N+, and P+) n-type 6H- and 4H-SiC. DLTS of room- and high-temperature ion-implanted 6H-SiC:Mg and :Cr indicate a dramatic increase in both the activation of the ion-implanted atoms and the damage recovery of the crystalline lattice with an elevated ion-implantation temperature. The effects of high-temperature annealing, from 1200 to 1800°C, on both damage-recovery and ion activation are measured and analyzed. Trap parameters of the deep level defects are determined, including the identification of a 615 meV V_Si-N_C defect. Double-correlated DLTS measurements indicate a one-dimensional distribution of the various defects, and surface diffusion of ion-implanted Mg during high-temperature annealing. Electrical measurements of 6H-SiC:Mg and :Cr diodes indicate the effect of annealing temperature and ion species on the midgap level defect concentration. CL measurements indicate the formation of deep radiative centers in 500°C ion-implanted 4H-SiC:P and :N. Optimum anneal temperatures are determined for activation of ion-implanted N and P. CL measurements indicate the presence of a 130 meV higher energy conduction band minimum.