NITROGEN ION-IMPLANTATION INTO 6H-SIC AND APPLICATION TO HIGH-TEMPERATURE, RADIATION-HARD DIODES

Ion implantation of nitrogen (N) into 6H-SiC{0001} epilayers was syste matically investigated. The N profiles simulated with a TRIM (transpor t of ions in matter) program showed good agreement with experimental r esults when the tilt angle was set larger than 5 degrees. The sheet re sistance of implanted layers decreased with increasing annealing tempe rature, and a low sheet resistance of 820 Omega/square was obtained by annealing at 1600 degrees C. The implanted p-n junction diodes showed a small reverse leakage current of 2.9 x 10(-9) A/cm(2) at a bias vol tage of -10 V, and a high breakdown voltage of 446 V at room temperatu re. The diodes operated with good rectification at a high temperature of 350 degrees C. The characteristics of the diodes showed very Little change after gamma-ray irradiation with total doses up to 10 Mrad.