Anomalous Spectral Shape Evolution of Ge Raman Shift in Oxidation of SiGe

This paper reports anomalous Raman peak shape of Ge in SiGe oxidation. The results in Raman spectroscopy in SiGe suggest that Ge precipitation occurs at the SiGe interface associated with the oxidation. Non-oxidized Ge remaining at the interface should be related to the interface degradation which should lead to poor gate stack properties. Finally, it discusses how to achieve well-behaved SiGe gate stacks by considering anomalous Raman spectrum in the oxidation.