METHOD FOR FABRICATING A TRANSISTOR WITH A RAISED SOURCE-DRAIN STRUCTURE

摘要

A method for forming a transistor includes defining agate structure on a top surface of a first semiconductor layer of a silicon-on-insulator (SOI) substrate. The gate structure includes an insulating cover. A second semiconductor layer is then conformally deposited. The deposited second semiconductor layer includes an epitaxial portion on surfaces of the first semiconductor layer and an amorphous portion on surfaces of the insulating cover. The amorphous portion is then removed using a selective etch. The remaining epitaxial portion forms faceted raised source-drain structures on either side of the transistor gate structure. A slope of the sloped surface for the facet is dependent on the process parameters used during the conformal deposition.

主权项

1. A method, comprising:
forming a transistor gate structure on a top surface of a first semiconductor layer of a silicon-on-insulator (SOI) substrate, wherein the transistor gate structure includes sidewall spacers and a cover; conformally depositing a second semiconductor layer, wherein the second semiconductor layer has an epitaxial portion on surfaces of the first semiconductor layer and an amorphous portion on surfaces of the sidewall spacers and cover; and selectively etching to remove the amorphous portion leaving the epitaxial portion to form faceted raised source-drain structures on either side of the transistor gate structure.