Metal oxide field effect transistor with a sharp halo

US7859013B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Huajie Chen · Danbury, US
• Judson R. Holt · Wappingers Falls, US
• Rangarajan Jagannathan · Hopewell Junction, US
• Wesley C. Natzle · New Paltz, US
• Michael Sievers · Poughkeepsie, US
• Richard S. Wise · Beacon, US

Key dates

• Filing date: Dec 13, 2007
• Grant date: Dec 28, 2010
• Expiry date: Mar 12, 2028

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D30/0227

Abstract

Disclosed are embodiments of a MOSFET with defined halos that are bound to defined source/drain extensions and a method of forming the MOSFET. A semiconductor layer is etched to form recesses that undercut a gate dielectric layer. A low energy implant forms halos. Then, a COR pre-clean is performed and the recesses are filled by epitaxial deposition. The epi can be in-situ doped or subsequently implanted to form source/drain extensions. Alternatively, the etch is immediately followed by the COR pre-clean, which is followed by epitaxial deposition to fill the recesses. During the epitaxial deposition process, the deposited material is doped to form in-situ doped halos and, then, the dopant is switched to form in-situ doped source/drain extensions adjacent to the halos. Alternatively, after the in-situ doped halos are formed the deposition process is performed without dopants and an implant is used to form source/drain extensions.