Source of surface morphological defects formed on 4H-SiC homoepitaxial films

Plan-view transmission electron microscopy (TEM) was carried out to investigate the source of morphological defects formed on the surface of 4H–SiC homoepitaxial films. The source at the substrate/epifilm interface consisted of an inclusion and partial dislocations emerging from it. Selected-area diffraction pattern analysis, energy dispersive X-ray spectroscopy and micro-Raman spectroscopy revealed that the chemical composition of the inclusion was ZrO2. From the comparison between TEM images and calculated images, it was suggested that the partial dislocations were sheared Frank dislocations with the Burgers vector of the (1/12) type.