Ion Implantation Induced Defects in 6H-SiC and Their Annealing Behaviour

Fourfold Al+ implantations into 6H-SiC have been carried out in order to create a laterally structured p-doped layer. This way, a 400 nm thick box-shaped Al profile with a concentration plateau of 5x1019 cm-3 buried 200 nm below the SiC surface could be realized. The defects caused by the ion implantation should be minimized by implantation at higher substrate temperatures and post implantation annealing. In addition to the traditional furnace annealing a flash lamp annealing has been used. The defect structure after implantation and annealing has been investigated by Slow Positron Implantation Spectroscopy (SPIS). It could be shown that vacancies and vacancy agglomerates can be removed using furnace annealing at 1650 0C. However, dislocation loops in the implantation region remain stable at this temperature. Using flash lamp annealing a further defect removal could be observed.