Methods for Fabricating Strained Gate-All-Around Semiconductor Devices by Fin Oxidation Using an Undercut Etch-Stop Layer

摘要

Strained gate-all-around semiconductor devices formed on globally or locally isolated substrates are described. For example, a semiconductor device includes a semiconductor substrate. An insulating structure is disposed above the semiconductor substrate. A three-dimensional channel region is disposed above the insulating structure. Source and drain regions are disposed on either side of the three-dimensional channel region and on an epitaxial seed layer. The epitaxial seed layer is composed of a semiconductor material different from the three-dimensional channel region and disposed on the insulating structure. A gate electrode stack surrounds the three-dimensional channel region with a portion disposed on the insulating structure and laterally adjacent to the epitaxial seed layer.

主权项

1. A method of fabricating a semiconductor device, the method comprising:
forming a three-dimensional semiconductor structure on an epitaxial seed layer disposed above a semiconductor substrate, the epitaxial seed layer comprising a semiconductor material different from the three-dimensional semiconductor structure; etching the three-dimensional semiconductor structure to provide a three-dimensional channel region and to expose portions of the epitaxial seed layer on either side of the three-dimensional channel region; forming source and drain regions on either side of the three-dimensional channel region and on the epitaxial seed layer; insulating the three-dimensional channel region and the source and drain regions from the semiconductor substrate by forming an insulating structure comprising one or more isolation pedestals continuous with the semiconductor substrate; and, subsequently, removing a portion of the epitaxial seed layer; forming a gate electrode stack at least partially surrounding the three-dimensional channel region; and forming a pair of conducting contacts, one contact at least partially surrounding the source region, and another contact at least partially surrounding the drain region.