Thick, high quality 4H-SiC epilayers have been grown in a vertical hot-wall chemical vapor deposition system at a high growth rate on (0001) 8 0 off-axis substrates. We discuss the use of dichlorosilane as the Si-precursor for 4H-SiC epitaxial growth as it provides the most direct decomposition route into SiCl 2 , which is the predominant growth species in chlorinated chemistries. A specular surface morphology was attained by limiting the hydrogen etch rate until the system was equilibrated at the desired growth temperature. The RMS roughness of the grown films ranged from 0.5-2.0 nm with very few morphological defects (carrots, triangular defects, etc.) being introduced, while enabling growth rates of 30-100 µm/hr, 5-15 times higher than most conventional growths. Site-competition epitaxy was observed over a wide range of C/Si ratios, with doping concentrations < 1x10 14 cm -3 being recorded. X-ray rocking curves indicated that the epilayers were of high crystallinity, with linewidths as narrow as 7.8 arcsec being observed, while microwave photoconductive decay (µPCD) measurements indicated that these films had high injection (ambipolar) carrier lifetimes in the range of 2 µs.3

Thick and high quality 4H-SiC epilayers have been grown in a vertical hot-wall chemical vapor deposition system at a high growth rate on (0001) 8 0 off-axis substrates. We discuss the use of dichlorosilane as the Si-precursor for 4H-SiC epitaxial growth as it provides the most direct decomposition route into SiCl 2 , which is the predominant growth species in chlorinated chemistries. The RMS roughness of the films ranged from 0.5-2.0 nm with very few morphological defects (carrots, triangular defects, etc.) being introduced, while enabling growth rates of 30-100 µm/hr, 5-15 times higher than most conventional growths. A specular surface morphology was attained by limiting the hydrogen etch rate until the system was equilibrated at the desired growth temperature. Site-competition epitaxy was observed over a wide range of C/Si ratios, with doping concentrations as low as 2x10 14 cm -3 being recorded. X-ray rocking curves indicated that the epilayers were of high crystallinity, with linewidths as narrow as 7.8 arcsec being observed, while microwave photoconductive decay (µPCD) measurements indicated that these films had high injection (ambipolar) carrier lifetimes in the range of 2 µs. These films also appeared to be free of polytype inclusions.

The effect of using SiO2 capping layer during Al implant activation anneal on the performance of 4H-SiC P-i-N diodes has been investigated. Two sets of 4H-SiC pin diode samples, one with SiO2 cap and another with graphite cap, were annealed under high temperatures of 1500°C for activation after Al implantation at 650°C to form the p-type active region and the JTE region. The surface stoichiometry of annealed SiC was examined by x-ray photoelectron spectroscopy (XPS). Various material and device parameters including surface roughness, sheet resistance, minimum forward leakage current and maximum breakdown voltage have been extracted for comparison. The results show that SiO2 cap effectively protects the SiC surface during high temperature implant annealing.