On the nature of ion implantation induced dislocation loops in 4H-silicon carbide

Transmission electron microscopy was used to investigate B-11, C-12, N-14, Al-27, Si-28, and Ar-37 ion-implanted 4H-SiC epilayers and subsequent defect formation after high temperature annealing. During the annealing process extrinsic dislocation loops of interstitial type are formed on the SiC basal plane with a depth distribution roughly corresponding to the distribution of the implanted ions. The investigation reveals that in samples where the implanted ions are substituting for a position in the silicon sublattice, generating an excess of interstitial silicon, the dislocation loops are more readily formed than in a sample implanted with an ion substituting for carbon. (C) 2002 American Institute of Physics.