Method for manufacturing trench-type power device

• Main Author: SHEN SIJIE
• Format: Patent
• Language: Chinese; English
• Published: 06.04.2016
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The invention provides a method for manufacturing trench-type power device. The method comprises a step of forming a mask layer pattern at the terminal area of a substrate through first time of photolithography and etching, and executing ion injection to form a protective ring, a step of depositing a mask material layer, partly filling the pattern of the mask layer, and forming a groove at the device area of the substrate through second time of photolithography and etching, a step of forming a side wall at the side wall of the groove, a step of etching a trench in the substrate by using the mask layer structure with the formation of the side wall, and filling the trench with a polysilicon material, a step of removing the side wall at the side wall of the groove, and executing ion injection such that injection areas are formed at two sides of a polysilicon structure, a step of forming an injection mask pattern through the third time of photolithography, and injecting the substrate by using the injection mask p