Study of nitrogen, aluminium and boron incorporation in SiC layers grown by sublimation epitaxy

Abstract

Sublimation epitaxy is a growth technique viable for SiC epilayer fabrication since the method is technologically simple, the growth rate is high (up to 100 μm/h) and the as-grown surfaces are very smooth. However, the remaining issues of purity and intentional doping control need to be studied and the behaviour understood before this method can be applied to device fabrication. We will show results of nitrogen, aluminium and boron incorporation in layers grown by sublimation epitaxy. The epilayers have been studied using electrical, secondary ion mass spectrometry and cathodoluminescence measurements as well as by low-temperature photoluminescence spectroscopy. Possible solutions to lower especially the nitrogen concentrations in epilayers are presented along with experimental results leading to epilayer net doping concentrations in the N D− N A∼10 15 cm −3 range.