Depletion Of Charge Carriers Research Articles

1131. Growth, processing and characterization of beta-silicon carbide single crystals

Abstract : A study of epitaxial vapor deposition of beta-silicon carbide on solution grown beta-silicon carbide surfaces was initiated. A literature survey and design and construction of a versatile vapor deposition apparatus were complete. Continuously oriented (111)/(111) beta-silicon carbide deposits were obtained by pyrolysis of methyltrichlorosilane and, independently, silane/propane mixtures. Oxidation experiments were conducted on solution grown beta-silicon carbide platelets in dry oxygen and steam. The oxidation kinetics in the parabolic (diffusion controlled) rate region are identical with those of silicon. Oxide films free of pinhole defects were obtained only by dry oxidation. Metal-oxide-semiconductor structures were fabricated using evaporated aluminum and their capacitance-voltage characteristics were determined at 100 kc. The dielectric constant of the oxide is k = 3.9, as expected for silicon dioxide. Depletion of charge carriers in the semiconductor adjacent to the oxide interface under a dc bias on the aluminum gate was demonstrated through the resulting change in capacitance with gate voltage. The variation in capacitance increased with decreasing oxide film thickness and the results were consistent with the expected net donor concentration in these crystals. (Author)