Process for forming gate oxide layer

• Main Authors: TSENG MAO-SONG, CHANG CHIEN-PING, CHANG SU-WEN, CHUANG CHIAO-SHUN
• Format: Patent
• Language: English
• Published: 17.01.2002
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A process for forming a gate oxide layer of a trench power MOSFET is provided. The process includes steps of providing a silicon substrate, forming a mask layer on the silicon substrate, removing a portion of the mask layer to expose a portion of the silicon substrate, removing the exposed portion of the silicon substrate to form the trench, removing remaining portion of the mask layer, forming a sacrificial oxide layer on the silicon substrate and on the bottom and sidewall of the trench by thermal oxidation under an operating temperature ranged from 1150 to 1300° C. and an operating time ranged from 20 to 60 minutes, removing the sacrificial oxide layer, and forming a gate oxide layer on the silicon substrate and on the bottom and sidewall of the trench.