Low-cost strained soi substrate for high-performance cmos technology

Abstract

A cost-effective and simple method of fabricating strained semiconductor-on-insulator (SSOI) structures which avoids epitaxial growth and subsequent wafer bonding processing steps is provided. In accordance with the present invention, a strain-memorization technique is used to create strained semiconductor regions on a SOI substrate. The transistors formed on the strained semiconductor regions have higher carrier mobility because the Si regions have been strained. The inventive method includes (i) ion implantation to create a thin amorphization layer, (ii) deposition of a high stress film on the amorphization layer, (iii) a thermal anneal to recrystallize the amorphization layer, and (iv) removal of the stress film. Because the SOI substrate was under stress during the recrystallization process, the final semiconductor layer will be under stress as well. The amount of stress and the polaity (tensile or compressive) of the stress can be controlled by the type and thickness of the stress films.