Chapter XIII semiconducting compounds

Amelinckx (1) studied growth spirals on SiC and found their form in agreement with the theory of Burton & Cabrera. Weill (2) observed a constant spiral spacing on SiC of 15 microns and a critical nucleus size of 1.2 microns at 0.4% supersaturation. Ramsdell and Mitchell (3) report a new hexagonal polymorph of silicon carbide and Baumann (4) studied several methods of preparing SiC. While pure silicon and carbon react only at the melting point of silicon, Baumann was able to prepare β SiC at 525°C by reacting carbon with a silicon-aluminum-zinc alloy. He also observed that the formation of SiC from SiO2 and carbon proceeds through the initial formation of elemental silicon at approximately 1500°C. He found the transformation of β SiC to α SiC at 2100°C.