Reduced 1/f noise in p-Si0.3Ge0.7 metamorphic metal–oxide–semiconductor field-effect transistor

Abstract

We have demonstrated reduced 1/f low-frequency noise in sub-μm metamorphic high Ge content p- Si 0.3 Ge 0.7 metal–oxide–semiconductor field-effect transistors (MOSFETs) at 293 K. Three times lower normalized power spectral density (NPSD) S I D /I D 2 of drain current fluctuations over the 1–100 Hz range at V DS =−50 mV and V G −V th =−1.5 V was measured for a 0.55 μm effective gate length p- Si 0.3 Ge 0.7 MOSFET compared with a p- Si MOSFET. Performed quantitative analysis clearly demonstrates the importance of carrier number fluctuations and correlated mobility fluctuations (CMFs) components of 1/f noise for p- Si surface channel MOSFETs, and the absence of CMFs for p- Si 0.3 Ge 0.7 buried channel MOSFETs. This explains the reduced NPSD for p- Si 0.3 Ge 0.7 MOSFETs in strong inversion.