Laterally scaled Si-Si_0.7Ge_0.3 n-MODFETs with f_max > 200 GHz and low operating bias

We report on the dc and RF characterization of laterally scaled, Si - SiGe n-MODFETs. Devices with gate length, Lg, of 80 nm had fT = 79 Ghz and fmax = 212 Ghz, while devices with Lg = 70 nm had fT as high as 92 Ghz. The MODFETs displayed enhanced fT at reduced drain-to-source voltage, Vds, compared to Si MOSFETs with similar fT at high Vds. © 2005 IEEE.