Method and structure for improving finFET with epitaxy source/drain

摘要

Isolation structures are formed to laterally surround a gate material block such that each sidewall of the gate material block abuts a corresponding sidewall of the isolation structures. Sidewalls of the gate material bock define ends of gate structures to be subsequently formed. The isolation structures obstruct lateral growth of a semiconductor material during a selective epitaxial grown process in formation of source/drain regions, thereby preventing merging of the source/drain regions at the ends of gate structures. As a result, a lateral distance between each sidewall of the gate material block and a corresponding outermost sidewall of an array of a plurality of semiconductor fins can be made sufficiently small without causing the electrical shorts of the source/drain regions.

主权项

1. A semiconductor structure comprising:
a plurality of semiconductor fins located on a region of a substrate; at least one gate structure overlying a channel portion of each of the plurality of semiconductor fins; an epitaxial source region located on a first side of the at least one gate structure, the epitaxial source region merging the plurality of semiconductor fins on the first side; an epitaxial drain region located on a second side of the at least one gate structure opposite the first side, the epitaxial drain region merging the plurality of semiconductor fins on the second side; a first isolation structure located at a first end of each of the at least one gate structure, the epitaxial source region and the epitaxial drain region, wherein the first isolation structure has a sidewall abutting the first end of each of the at least one gate structure, the epitaxial source region and the epitaxial drain region; and a second isolation structure located at a second end of each of the at least one gate structure, the epitaxial source region and the epitaxial drain region opposite the first end, wherein the second isolation structure has a sidewall abutting the second end of each of the at least one gate structure, the epitaxial source region and the epitaxial drain region, wherein each of the first isolation structure and the second isolation structure has a topmost surface coplanar with a topmost surface of the at least one gate structure.