Effects of Strained Silicon Layer on Nickel (Germano)silicide for Nanoscale Complementary Metal Oxide Semiconductor Field-Effect Transistor Device

Abstract

The effects of a strained silicon layer on the thermal stability of nickel (germano)silicide for nanoscale complementary metal oxide semiconductor field-effect transistor (CMOSFET) devices are discussed in this study. Three different thicknesses, 5, 13, and 40 nm, of silicon layers on silicon germanium (SiGe) were prepared for this experiment. The effects of the silicidation rapid thermal annealing (RTA) temperature and postsilicidation annealing temperature for the different silicon layer thicknesses were studied. For comparison, a bulk silicon substrate and a SiGe substrate were also used. Silicides with the thin strained silicon layers (5 and 13 nm) on SiGe showed good thermal stability in this study. However, the other silicides using bulk silicon, 40-nm-thick silicon on SiGe, and the SiGe substrate underwent degradation due to silicide agglomeration during annealing. A SiO2 layer was found on the silicide using the SiGe substrate. In this study, several analysis methods such as four-point probe measurement, field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and Auger electron spectroscopy (AES) were used for detailed study.