DEEP-LEVEL TRAPS IN THE EXTENDED TAIL REGION OF BORON-IMPLANTED N-TYPE 6H-SIC

Deep traps in the boron extended tail region of ion implanted 6H-SiC p n junctions formed during annealing have been studied using deep level transient spectroscopy. Dramatically high concentrations of similar t o 10(16) cm(-3) of the D center have been observed through the unusual appearance of minority peaks in the majority carrier spectra. No evid ence is found for any shallow boron acceptor in this region, but an in duced hole trap I-h at E-V+0.46 eV is found under cold implantation co nditions. These results support the picture of the extended tail, rich in boron-vacancy complexes such as the D center, which forms as a res ult of vacancy enhanced indiffusion. The dominance of the electrically active D center in the depletion layer of the technologically importa nt SIC pn junction diode suggests the need for further research in thi s area. (C) 1998 American Institute of Physics.