ALUMINUM NITRIDE-SILICON CARBIDE SOLID-SOLUTIONS GROWN BY PLASMA-ASSISTED, GAS-SOURCE MOLECULAR-BEAM EPITAXY

Solid solutions of aluminum nitride (AlN) and silicon carbide (SiC) ha ve been grown at 900-1300 degrees C on vicinal alpha(6H)-SiC(0001) sub strates by plasma-assisted, gas-source molecular beam epitaxy, Under s pecific processing conditions, films of (AlN)(x)(SiC)(1-x) with 0.2 le ss than or equal to x less than or equal to 0.8, as determined by Auge r electron spectrometry (AES), were deposited. Reflection high-energy electron diffraction (RHEED) was used to determine the crystalline qua lity, surface character, and epilayer polytype. Analysis of the result ing surfaces was also performed by scanning electron microscopy (SEM). High-resolution transmission electron microscopy (HRTEM) revealed tha t monocrystalline films with x greater than or equal to 0.25 had the w urtzite (2H) crystal structure; however, films with x < 0.25 had the z incblende (3C) crystal structure.