Trench gate semiconductor device and method for making the same

US11374123B2 · kind B2 · utility

Assignee

• Shanghai Huahong Grace Semiconductor Manufacturing Corporation · CN

Inventors

• Jiye YANG · Shanghai, CN
• Longjie Zhao · Shanghai, CN
• Hao Li · Nanhu, CN

Key dates

• Filing date: Aug 19, 2020
• Grant date: Jun 28, 2022
• Expiry date: Aug 19, 2040

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/685

Abstract

The present disclosure discloses a trench gate semiconductor device, wherein a trench gate includes a trench formed in a semiconductor substrate, and a gate oxide layer formed on a bottom surface and a side surface of the trench; the gate oxide layer is formed by stacking a first oxide layer and a second oxide layer; the first oxide layer is a furnace tube thermal oxide layer; the second oxide layer is a PECVD oxide layer; the gate oxide layer has a thermally densified structure processed by means of RTA. The present disclosure also discloses a method for manufacturing a trench gate semiconductor device. The present disclosure can increase BVGSS of the device, without affecting the threshold voltage of the device, with simple processes and low costs.