Silicon nanotube MOSFET

US8871576B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Daniel Tekleab · Wappingers Falls, US
• Hung H. Tran · Chicago, US
• Jeffrey W. Sleight · Ridgefield, US
• Dureseti Chidambarrao · Weston, US

Key dates

• Filing date: Feb 28, 2011
• Grant date: Oct 28, 2014
• Expiry date: Feb 10, 2033

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D30/63
• WIPO field: Micro-structural and nano-technology
• WIPO sector: Chemistry

Abstract

A nanotubular MOSFET device and a method of fabricating the same are used to extend device scaling roadmap while maintaining good short channel effects and providing competitive drive current. The nanotubular MOSFET device includes a concentric tubular inner and outer gate separated from each other by a tubular shaped epitaxially grown silicon layer, and a source and drain respectively separated by spacers surrounding the tubular inner and outer gates. The method of forming the nanotubular MOSFET device includes: forming on a substrate a cylindrical shaped Si layer; forming an outer gate surrounding the cylindrical Si layer and positioned between a bottom spacer and a top spacer; growing a silicon epitaxial layer on the top spacer adjacent to a portion of the cylindrical shaped Si layer; etching an inner portion of the cylindrical shaped Si forming a hollow cylinder; forming an inner spacer at the bottom of the inner cylinder; forming an inner gate by filling a portion of the hollow cylinder; forming a sidewall spacer adjacent to the inner gate; and etching a deep trench for accessing and contacting the outer gate and drain.