The movement of basal plane dislocations (BPDs) in SiC enhanced the formation of stacking faults, which were believed to be a major hindrance in realizing SiC based bipolar devices of high performance and reliability for high power device applications. A first report was made of the evolution and stability of BPDs in highly p-type doped SiC, as compared with conventional highly n-type doped SiC for improved bipolar devices. Using sequentially doped p-type/n-type/p-type SiC single crystals (sequential doping was done in single growth runs) an investigation was made of the occurrence of BPDs in n-type doped SiC versus p-type doped SiC to address their evolution and stability depending on doping type. It was found that BPDs were absent or appear significantly less pronounced in p-type doped SiC as compared to n-type doped SiC, a phenomenon which was of great importance to the stacking fault problem in SiC and hence to the performance and reliability of SiC based bipolar devices.

Evolution and Stability of Basal-Plane Dislocations during Bulk Growth of Highly n-Type Doped versus Highly p-Type Doped 6H-SiC. S.A.Sakwe, R.Müller, D.Queren, U.Künecke, P.J.Wellmann: Physica Status Solidi C, 2006, 3[3], 567-70