US 6,720,630 B2 · Structure and method for MOSFET with metallic gate electrode

Abstract

A method of forming a metal oxide semiconductor field effect transistor (MOSFET) having a metallic gate electrode that is protected with hanging sidewall spacers during a subsequent gate oxidation process is provided. A semiconductor structure formed by the inventive method is also provided. Specifically, the inventive semiconductor structure includes a semiconductor substrate comprising a patterned gate region formed atop a patterned gate dielectric, the patterned gate region includes at least a metallic gate electrode formed atop a polysilicon gate electrode; hanging sidewall spacers formed on an upper portion of the patterned gate region including the metallic gate electrode; and a thermal oxide layer formed on lower portions of patterned gate region including a portion of the polysilicon gate electrode, but not the metallic gate electrode.

Claims21

Dependent claims

A semiconductor structure comprising:

a semiconductor substrate comprising a patterned gate region located atop a patterned gate dielectric, said patterned gate region including at least a metallic gate electrode located atop a polysilicon gate electrode;
sidewall spacers positioned on an upper portion of said patterned gate region including at least said metallic gate electrode, said sidewall spacers have a first thickness;
and
a thermal oxide layer having a second thickness located on lower portions of said patterned gate region including a portion of said polysilicon gate electrode but not said metallic gate electrode, wherein said first thickness is greater than said second thickness, and a differential between said first thickness and said second thickness forms a recess.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

09/867,874Filed 30 May 2001

Published

US 2002/0182822 A15 Dec 2002

Granted

13 Apr 2004

Term ends

Not estimatedThe source records don’t support an estimate.

Classification8 codes

H10D 64/01354
The insulator being formed after the semiconductor body, the semiconductor being silicon: passivation or protection of the electrode, e.g. using…
H10D 30/0227
Having source and drain regions or source and drain extensions self-aligned to sides of the gate: having both lightly-doped source and drain…
H10D 64/015
Manufacture or treatment: removing at least parts of gate spacers, e.g. disposable spacers
H10D 64/017
Manufacture or treatment: using dummy gates in processes wherein at least parts of the final gates are self-aligned to the dummy gates, i.e.…

Structure and method for MOSFET with metallic gate electrode

Life of this patent

Structure and method for MOSFET with metallic gate electrode

Life of this patent

Abstract

Claims21