FORMING A CMOS WITH DUAL STRAINED CHANNELS

摘要

The present invention relates generally to a semiconductor device, and more particularly, to a structure and method of forming a compressive strained layer and a tensile strained layer on the same wafer. A lower epitaxial layer may be formed adjacent to a tensile strained layer. An upper epitaxial layer may be formed over a portion of the lower epitaxial layer. Thermal oxidation may convert the upper epitaxial layer to an upper oxide layer, and thermal condensation may causes a portion of the lower epitaxial layer to become a compressive strained layer. The upper oxide layer and a remaining portion of the lower epitaxial layer may be removed, leaving the tensile strained layer and the compressive strained layer.

主权项

1. A method comprising:
forming a tensile strained layer on an upper surface of a substrate, the tensile strained layer comprising a tensile strained semiconductor material; and forming an epitaxial layer on the upper surface of the substrate, the epitaxial layer adjacent to the tensile strained layer; forming an upper epitaxial layer on an upper surface of the epitaxial layer; and performing a thermal oxidation process, such that the upper epitaxial layer is converted to an oxide and thermal condensation causes a portion of the epitaxial layer below to become a compressive strained layer.