Comparison of Graphite and BN/AlN Annealing Caps for Ion Implanted SiC

Abstract

4H-SiC samples implanted with 1020 Al were annealed at various temperatures with a BN/AlN or graphite cap, and there morphological, structural, and electrical properties are compared. No blow holes were observed in either cap. Some Si out-diffuses through the graphite cap which results in a rougher surface and a structurally modified region near the surface. The BN/AlN cap annealed at 1800°C cannot be readily removed, whereas the graphite cap can be removed easily after any annealing temperature. The sheet resistances for both types of samples were about the same.