Raised epitaxial LDD in MuGFETs and methods for forming the same

US9941368B2 · kind B2 · utility

Assignee

• TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD. · TW

Inventors

• Yonag-Yan Lu · Baoshan, TW
• Hou-Yu Chen · Zhubei City, TW
• Shyh-Horng Yang · Hsinchu, TW

Key dates

• Filing date: Dec 1, 2016
• Grant date: Apr 10, 2018
• Expiry date: Dec 1, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D30/6213

Abstract

Embodiments include Multiple Gate Field-Effect Transistors (MuGFETs) and methods of forming them. In an embodiment, a structure includes a substrate, a fin, masking dielectric layer portions, and a raised epitaxial lightly doped source/drain (LDD) region. The substrate includes the fin. The masking dielectric layer portions are along sidewalls of the fin. An upper portion of the fin protrudes from the masking dielectric layer portions. A first spacer is along a sidewall of a gate structure over a channel region of the fin. A second spacer is along the first spacer. The raised epitaxial LDD region is on the upper portion of the fin, and the raised epitaxial LDD region adjoins a sidewall of the first spacer and is disposed under the second spacer. The raised epitaxial LDD region extends from the upper portion of the fin in at least two laterally opposed directions and a vertical direction.