Silicon carbide substrate
According to different downstream application fields, the core classifications include:
1) Conductive type: It can be further processed into power devices such as Schottky diodes, MOSFETs, IGBTs, etc., and applied in fields such as new energy vehicles, rail transit, and high-power transmission and transformation.
2) Semi insulating type: It can be further used to produce microwave and radio frequency devices such as HEMTs, which are applied in fields such as information communication and radio detection.
The preparation of silicon carbide substrates belongs to a technology and process intensive industry, and the core process flow includes:
1)Raw material synthesis involves mixing high-purity silicon powder and carbon powder according to a formula, and reacting them in a reaction chamber at high temperatures above 2000 ℃ to synthesize silicon carbide particles with specific crystal forms and particle sizes. Through processes such as crushing, screening, and cleaning, high-purity silicon carbide powder raw materials that meet the requirements for crystal growth are produced.
2) Crystal growth, currently the mainstream process in the market is PVT gas-phase transport method. Heat the silicon carbide powder in a closed and vacuum growth chamber at 2300 ° C to sublime it into a reaction gas. Afterwards, it is transferred to the surface of the seed crystal for atomic deposition, growing into silicon carbide single crystals.
3) Crystal processing mainly includes processes such as ingot processing, ingot cutting, grinding, polishing, cleaning, etc., ultimately forming a silicon carbide substrate.