Structure and method for forming a trench MOSFET having self-aligned features

US6916745B2 · kind B2 · utility

Assignee

• FAIRCHILD SEMICONDUCTOR CORPORATION · US

Inventors

• Robert Herrick · Lompoc, US
• Becky Losee · Cedar Hills, US
• Dean E. Probst · West Jordan, US

Key dates

• Filing date: May 20, 2003
• Grant date: Jul 12, 2005
• Expiry date: May 20, 2023

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S257/905

Abstract

In accordance with an embodiment of the present invention, a semiconductor device is formed as follows. An exposed surface area of a silicon layer where silicon can be removed is defined. A portion of the silicon layer is removed to form a middle section of a trench extending into the silicon layer from the exposed surface area of the silicon layer. Additional exposed surface areas of the silicon layer where silicon can be removed are defined. Additional portions of the silicon layer are removed to form outer sections of the trench such that the outer sections of the trench extend into the silicon layer from the additional exposed surface areas of the silicon layer. The middle section of the trench extends deeper into the silicon layer than the outer sections of the trench.