Reduced 1/f noise in p-Si[sub 0.3]Ge[sub 0.7] metamorphic metal–oxide–semiconductor field-effect transistor.

We have demonstrated reduced 1/f low-frequency noise in sub-μm metamorphic high Ge content p-Si[sub 0.3]Ge[sub 0.7] metal–oxide–semiconductor field-effect transistors (MOSFETs) at 293 K. Three times lower normalized power spectral density (NPSD) S[sub I[sub D]]/I[sub D][sup 2] of drain current fluctuations over the 1–100 Hz range at V[sub DS]=-50 mV and V[sub G]-V[sub th]=-1.5 V was measured for a 0.55 μm effective gate length p-Si[sub 0.3]Ge[sub 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[sub 0.3]Ge[sub 0.7] buried channel MOSFETs. This explains the reduced NPSD for p-Si[sub 0.3]Ge[sub 0.7] MOSFETs in strong inversion. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]