The structure and crystal quality of epitaxial films of SiC/AlN/6H-SiC(0001) prepared by chemical vapor deposition were evaluated by high resolution transmission electron microscopy (HRTEM) and x-ray diffraction techniques. Cross-sectional HRTEM revealed an abrupt AlN layer-6H-SiC substrate junction, but the transition between the AlN and SiC layers was much rougher, leading to the formation of a highly disordered SiC region adjacent to the interface. The AlN layer was relatively defect free, while the SiC layer contained many microtwins and stacking faults originating at the top SiC/AlN interface. The SiC layer was the 3C-polytype, as determined by double crystal x-ray rocking curves. The SiC layers were under in-plane compressive stress, with calculated defect density between 2-4 × 107 defects/cm-2.
- Chemical vapor deposition (CVD)
- High resolution transmission electron microscopy (HRTEM)
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry