80 nm gate-length Si/Si_0.7Ge_0.3 n-MODFET with 194 GHz f_max

DC and RF performance of scaled n-channel Si/SiGe modulation-doped field effect transistors (n-MODFETs) grown by ultra-high vacuum chemical vapour deposition is reported. Devices with source-to-drain spacing of 300 nm, and gate length of 80 nm (70 nm) displayed fmax = 194 GHz (175 GHz) and FT = 70 GHz (79 GHz).