Lely method![]()
OverviewThe Lely method produces bulk silicon carbide crystals through the process of sublimation. Silicon carbide powder is loaded into a graphite crucible, which is purged with argon gas and heated to approximately 2,500 °C (4,530 °F). The silicon carbide near the outer walls of the crucible sublimes and is deposited on a graphite rod near the center of the crucible, which is at a lower temperature.[2] Several modified versions of the Lely process exist, most commonly the silicon carbide is heated from the bottom end rather than the walls of the crucible, and deposited on the lid. Other modifications include varying the temperature, temperature gradient, argon pressure, and geometry of the system. Typically, an induction furnace is used to achieve the required temperatures of 1,800–2,600 °C (3,270–4,710 °F).[2]: 195 See alsoReferences
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