Direct imaging and optical activities of stacking faults in 4H-SiC homoepitaxial films

Abstract

Both Shockley- and Frank-type stacking faults (SFs) in 4H-SiC were directly observed by scanning electron microscopy (SEM) and their optical activities were investigated by cathodoluminescence technique. The Shockley-type SFs identified by transmission electron microscopy show strong luminescence at wavelength of 471 nm while the Frank-type ones emit the luminescence at 482 nm. Both types of SFs present bright contrast in in-lens SEM images while no obvious contrast in out-lens images. The positions of the SFs observed by SEM correlate well with those detected in cathodoluminescence images. The bright SF contrast in SEM is discussed.