Transistor having notched fin structure and method of making the same

US8759943B2 · kind B2 · utility

Assignee

• TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD. · TW

Inventors

• Chih-Hung Tseng · Taichung, TW
• Da-Wen Lin · Baoshan, TW
• Chien-Tai Chan · Hsinchu, TW
• Chia-Pin Lin · Dashulong, TW
• Li-Wen Weng
• An-Shen Chang · Wubei, TW
• Chung-Cheng Wu · Baoshan, TW

Key dates

• Filing date: Oct 8, 2010
• Grant date: Jun 24, 2014
• Expiry date: Jan 18, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D30/6212

Abstract

A transistor includes a notched fin covered under a shallow trench isolation layer. One or more notch may be used, the size of which may vary along a lateral direction of the fin. In some embodiments, The notch is formed using anisotropic wet etching that is selective according to silicon orientation. Example wet etchants are tetramethylammonium hydroxide (TMAH) or potassium hydroxide (KOH).