To overcome these challenges and obtain high quality 200mm SiC wafers,solutions are proposed:
In terms of 200mm seed crystal preparation, appropriate temperature field, flow field, and expanding assemblwere studied and designed to take into account crystal quality and expanding size; Starting with a 150mm SiCseed crystal, carry out seed crystal iteration to gradually expand the SiC crystal size until it reaches 200mm;Throuch multiple crystal growth and processing, gradually optimize the crystal quality in the crystal expandingarea, and improve the quality of 200mm seed crystals.
n terms of 200mm conductive crvstal and substrate preparation. research has optimized the temperature fieland flow field design for large size crystal growth, conduct 200mm conductive SiC crystal growth, and controldoping uniformity. After rough processing and shaping of the crystal, an 8-inch electrically conductive 4H-SiCingot with a standard diameter was obtained. After cutting, grinding, polishing, processing to obtain SiC 200mmwafers with a thickness of 525um or so.