Silicon MOSFETs with very low microwave noise

Abstract

Reports MOSFETs with noise figures as low as 0.9 dB at 2 GHz, the lowest achieved to date with Si FETs. The devices were fabricated in thin-film silicon-on-sapphire, with gate lengths (defined by optical lithography) drawn at 0.5 /spl mu/m. The devices employed T-gate structures, with extra added aluminum to minimize gate resistance. The microwave gain was high: f/sub max/ values were as high as 52 GHz (near record performance) for nMOS and 32 GHz far pMOS transistors; f/sub t/ values were 17 GHz and 13 GHz for nMOS and pMOS respectively.