Material and n-p junction characteristics of As- and Sb-implanted SiC

Single and multiple energy As and Sb implantations were performed into p-ty pe 6H-SiC epitaxial layers at room temperature (RT) and 800 degreesC. Secon dary ion mass spectrometry measurements showed severe implant loss for anne aling temperatures > 1500 degreesC. Rutherford backscattering spectroscopy/ channeling (RBS/C) measurements indicated a high degree of residual lattice damage for RT implantations even after 1600 degreesC annealing while less damage was detected in 800 degreesC implanted samples. Electrical activatio ns (ratios of sheet carrier concentrations to implant doses) of 11 and 20% were measured for 800 degreesC As and Sb implantations annealed at 1500 deg reesC, respectively. The Schottky capacitance-voltage profiling measurement s indicated substitutional concentrations in the low 10(18) cm(-3) range fo r both As and Sb. Based on the experimental data, carrier ionization energi es of 130 and 88 meV were estimated for As and Sb donors, respectively. Ver tical n-p junction diodes were made by using multiple energy As and Sb impl anted epitaxial layers Elevated temperature As implanted diodes exhibited a room temperature reverse leakage current of approximate to 8 x 10 A/cm(2) with no passivation at - 100 V bias and a forward series resistance of 460 Ohm. (C) 2000 Elsevier Science B.V. All rights reserved.