The Role of Preamorphization and Activation for Ultra Shallow Junction Formation on Strained Si Layers Grown on SiGe Buffer

Abstract

In advanced CMOS technology nodes one may achieve further enhancement of device performance by carrier mobility modification in the transistor channel. The carrier mobility enhancement can be realized by formation of strained silicon layers on a Si_1−xGe_x strain relaxed buffer. Formation of source and drain extensions on such structures need to satisfy one additional requirement, the formation process, including the activation related thermal budget should not relax the strain in the channel. In this paper we separately investigate the role of amorphization during implantation, different doping impurities and thermal budget on the junction and the transistor channel regions properties. Two approaches of dopant activation are discussed: low temperature solid phase epitaxial regrowth and high temperature conventional spike.