Preparation method of silicon carbide VDMOS (Vertical Double-diffused Metal Oxide Semiconductor) capable of improving gate reliability

• Main Authors: ZHANG YUJIE, SHI GUANGYAN, ZHANG CHANGSHA, LI YUNJI
• Format: Patent
• Language: Chinese; English
• Published: 30.08.2024
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The invention provides a preparation method of a silicon carbide VDMOS (Vertical Double-diffused Metal Oxide Semiconductor) capable of improving gate reliability, which comprises the following steps of: depositing metal on the lower side surface of a silicon carbide substrate to form a drain metal layer; epitaxially growing on the silicon carbide substrate to respectively form a drift layer, a current sharing layer and a well region; forming a barrier layer above the well region, etching the barrier layer to form a through hole, and performing ion implantation on the well region to respectively form a P source region and an N type source region; removing the original barrier layer, forming a barrier layer again, etching the barrier layer, forming a through hole, performing metal deposition, and forming a source metal layer; removing the original barrier layer, forming a barrier layer again, etching the barrier layer, the well region and the current sharing layer, forming a through hole and a groove, and then