Replacement channels for semiconductor devices and methods for forming the same using dopant concentration boost

摘要

A replacement channel and a method for forming the same in a semiconductor device are provided. A channel area is defined in a substrate which is a surface of a semiconductor wafer or a structure such as a fin formed over the wafer. Portions of the channel region are removed and are replaced with a replacement channel material formed by an epitaxial growth/deposition process to include a first dopant concentration level less than a first dopant concentration level. A subsequent doping operation or operations is then used to boost the average dopant concentration to a level greater than the first dopant concentration level. The replacement channel material is formed to include a gradient in which the upper portion of the replacement channel material has a greater dopant concentration than the lower portion of replacement channel material.

主权项

1. A semiconductor transistor device comprising:
a substrate; a channel entirely contained within a layer of a single channel material disposed in an opening in the substrate, the channel material having a single base material, the base material comprising Ge or SiGe, and a dopant material with a dopant gradient having a continuous decrease in dopant concentration from a first dopant concentration on an upper surface of the channel to a second dopant concentration on a lower surface of the channel; and a transistor gate disposed over the channel material.