SUBLIMATION GROWTH OF SILICON CARBIDE SINGLE CRYSTALS

摘要

A method of forming large device quality single crystals of silicon carbide (33). A monocrystalline seed crystal (32) of silicon carbide of the desired polytype and a silicon carbide source powder (40) are introduced into a sublimation system and the source powder is heated to a temperature sufficient to enable it to sublime. The growth surface of the seed crystal is also heated to a somewhat lower temperature than that of the source powder and there is generated and maintained a constant flow of vaporized Si, Si2C and SiC2 per unit area per unit time from the source powder to the growth surface of the seed crystal. The constant flow is maintained by a method which includes maintaining a constant thermal gradient as measured between the growth surface of the seed crystal and the source powder as the crystal grows and the source powder is used up, while maintaining the growth surface of the seed crystal and the source powder at their respective different temperatures, thereby maintaining a constant growth rate of the single seed crystal and a consistent growth of a single polytype on the single growth surface thereof.