Growth and Characterization of Layered Structures of Silicon Carbide and Aluminum Nitride

Heterostructures of SiC and AlN in either sequence, AlN on SiC or SiC on AlN, were grown on Si, Al2O3, and 6H-SiC substrates by (metalorganic) chemical vapor deposition (CVD). On Si substrates, a SiC layer was first grown by a two-step technique and an AlN layer was deposited subsequently. On other substrates, an AlN layer was first grown, followed by SiC deposition. Multi-layered structures (SiC/AlN/SiC) were also produced to demonstrate the ability of heteroepitaxy of SiC and AlN on each other. AlN grown on 3C-SiC were highly oriented polycrystalline films. AlN films on 6H-SiC, SiC films on A1N/Al2O3, and SiC films on AlN/6H-SiC were single crystal. In the latter two cases, the SiC films were in hexagonal structure. These SiC films were smooth and specular in appearance and showed n-type conductivity.