Transistor with embedded Si/Ge material having enhanced across-substrate uniformity

US8334569B2 · kind B2 · utility

Assignee

• Advanced Micro Devices, Inc. · US

Inventors

• Robert Neil Mulfinger · York Haven, US
• Andy Wei · Queensbury, US
• Jan Hoentschel · Dresden, DE
• Casey Scott · Dresden, DE

Key dates

• Filing date: Apr 24, 2012
• Grant date: Dec 18, 2012
• Expiry date: Apr 24, 2032

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D84/038

Abstract

In sophisticated semiconductor devices, a strain-inducing semiconductor alloy may be positioned close to the channel region by forming cavities on the basis of a wet chemical etch process, which may have an anisotropic etch behavior with respect to different crystallographic orientations. In one embodiment, TMAH may be used which exhibits, in addition to the anisotropic etch behavior, a high etch selectivity with respect to silicon dioxide, thereby enabling extremely thin etch stop layers which additionally provide the possibility of further reducing the offset from the channel region while not unduly contributing to overall process variability.