Cathodoluminescence study of the properties of stacking faults in 4H-SiC homoepitaxial layers

Abstract

In-grown stacking faults in n-type 4H-SiC epitaxial layers have been investigated by real-color cathodoluminescence imaging and spectroscopy carried out at room and liquid helium temperatures. Stacking faults with 8H stacking order were observed, as well as double layer and multilayer 3C-SiC structures and a defect with an excitonic band gap at 2.635 eV. It was found that 8H stacking faults and triangular surface defects can be generated from similar nucleation sources. Time-resolved measurements reveal that compared to defect-free regions, the carrier lifetimes are severely reduced by the presence of stacking faults corresponding to triangular surface defects and three-dimensional 3C-SiC inclusions.