Temperature Dependence of Raman Peak Shift in Single-Crystalline Silicon-Germanium

Abstract

We demonstrate the relationship between Raman shift ω and temperature T (dω/dT) of silicon-germanium (SiGe) for Si–Si, Si–Ge, and Ge–Ge vibration modes which should be useful in local temperature evaluation of SiGe devices at submicron levels. We investigated the dω/dT of single-crystalline SiGe for Si–Si, Si–Ge, and Ge–Ge vibration modes and its dependence on the Ge fraction using variable-temperature Raman spectroscopy. We clarified that the (dω/dT)s for Si–Si, Si–Ge, and Ge–Ge are fairly constant for all single-crystalline SiGe samples. Therefore, the anharmonic vibration of Si–Si, Si–Ge, and Ge–Ge modes has no Ge-fraction dependence in SiGe. The peak shifts help define the temperature on the submicron-scale surface.