Trench power semiconductor device

US9991378B2 · kind B2 · utility

Assignee

• SINOPOWER SEMICONDUCTOR, INC. · TW

Inventors

• Po-Hsien Li · Tainan, TW
• Wei-Chieh Lin · Hsinchu, TW
• Jia-Fu Lin · Sanxing, TW
• Guo Yang · 安丰镇, CN

Key dates

• Filing date: Jun 20, 2016
• Grant date: Jun 5, 2018
• Expiry date: Jun 20, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/2527

Abstract

A trench power semiconductor device is provided. A trench gate structure of the trench power semiconductor device located in a cell trench of an epitaxial layer includes a first dielectric layer, a second dielectric layer, a gate electrode, a third dielectric layer, and a shielding layer. The second dielectric layer is interposed between the first and third dielectric layers, and the second dielectric layer is made from different material than the first dielectric layer. After performing a selective etching step on the second dielectric layer, a recess can be formed among the first, second and third dielectric layers. The gate electrode includes a conductive layer formed in the recess region, and the shielding electrode is surrounded by the third dielectric layer and insulated from the conductive layer.