Boron and aluminium doping by diffusion into n-type 4H–SiC Si-face substrates was carried out at the temperatures of 1800–2000C. Secondary ion mass spectroscopy was employed to obtain the impurity profiles, which showed that linearly graded boron profile and shallow aluminium profiles were achieved, which may be a promising application in SiC device fabrication, such as p–n diode or ohmic contact. Characterization of high temperature processing influence on SiC surface morphology was performed. Elemental boron and aluminium carbide were determined to be the best candidates as an impurity source materials for realizing p-type diffusion.

Boron and Aluminum Diffusion into 4H–SiC Substrates. A.Kubiak, J.Rogowski: Materials Science and Engineering B, 2011, 176[4], 297-300