Intel Corporation

Andrew N Westmeyer

Anand S Murthy

Michael L Hattendorf

Justin K Brask

Glenn A Glass

Nick Lindert

Jack Hwang

Jeffrey R Wank

Boyan Boyanov

Tahir Ghani

Some embodiments of the present invention include providing carbon doped regions and raised source/drain regions to provide tensile stress in NMOS transistor channels.

Strained NMOS transistor featuring deep carbon doped regions and raised donor doped source and drain

An MOS transistor formed on a heavily doped substrate is described. Metal gates are used in low temperature processing to prevent doping from the substrate from diffusing into the channel region of the transistor.

Metal gate transistors with raised source and drain regions formed on heavily doped substrate

This invention adds to the art of replacement source-drain cMOS transistors. Processes may involve etching a recess in the substrate material using one equipment set, then performing deposition in another. Disclosed is a method to perform the etch and subsequent deposition in the same reactor without atmospheric exposure. In-situ etching of the source-drain recess for replacement source-drain applications provides several advantages over state of the art ex-situ etching. Transistor drive current is improved by: (1) Eliminating contamination of the silicon-epilayer interface when the as-etched surface is exposed to atmosphere and (2) Precise control over the shape of the etch recess. Deposition may be done by a variety of techniques including selective and non-selective methods. In the case of blanket deposition, a measure to avoid amorphous deposition in performance critical regions is also presented.

CMOS transistor junction regions formed by a CVD etching and deposition sequence

The mobility of carriers may be increased in strained channel epitaxial source/drain transistors. Doped silicon material may be blanket deposited after removing ion implanted source/drain regions. The blanket deposition forms amorphous films over non-source/drain areas and crystalline films in source/drain regions. By using an etch which is selective to amorphous silicon, the amorphous material may be removed. This may avoid some problems associated with selective deposition of the doped silicon material.

Fabricating strained channel epitaxial source/drain transistors

A method is described for manufacturing an n-MOS semiconductor transistor. Recesses are formed in a semiconductor substrate adjacent a gate electrode structure. Silicon is embedded in the recesses via a selective epitaxial growth process. The epitaxial silicon is in-situ alloyed with substitutional carbon and in-situ doped with phosphorus. The silicon-carbon alloy generates a uniaxial tensile strain in the channel region between the source and drain, thereby increasing electron channel mobility and the transistor's drive current. The silicon-carbon alloy decreases external resistances by reducing contact resistance between source/drain and silicide regions and by reducing phosphorous diffusivity, thereby permitting closer placement of the transistor's source/drain and channel regions.

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Beaverton, OR, United States of America

Andrew N Westmeyer