Degradation of low frequency noise in SiGe- and SiGeC-surface channel $p$-type metal-oxide-semiconductor field effect transistor due to consuming the Si cap Available to Purchase

This letter reports on the noise degradation mechanism in SiGe- and SiGeC-surface channel $p$-type metal-oxide-semiconductor field-effect transistors $(pMOSFETs)$⁠. Compared to their Si reference, the surface SiGe $pMOSFETs$ show only slightly lower or even comparable noise (at low gate bias), while the SiGeC devices exhibit higher noise amplitude for the full bias range, unlike previously reported buried SiGe $pMOSFETs$ with significantly improved noise over their Si control. The degradation can be attributed to Si-cap consumption and thus the cancellation of buried channel operation. [C] incorporation further degrades noise characteristics due to inferior quality of epilayer and higher interface trap density.