Gate Length Scaling in High fMAX Si/SiGe n-MODFET

Abstract

The performances of strained channel Si/Si 0.6 Ge 0.4 n-MODFETs as a function of gatelength have been investigated experimentally at 300K . The direct-current, microwave and noise performances of devices with gatelengths ranging from 0.5 µm to 0.1 µm are presented. Maximum oscillation frequency f MAX of 158 GHz is obtained for a 0.1 X 100 µm with f T = 42 GHz and a minimum noise figure NF min = 0.5 dB at 2.5 GHz showing the potential of SiGe technology. The dependence of small signal, and noise parameters on gatelength and biases has been analyzed to assess the impact of non stationary transport and of short channel effects on the device behavior.

Scaling study of Si/SiGe MODFETs for RF applications

“…Heterostructure modulation doped field effect transistor (MODFETs) with ntype strained Si or p-type Ge channels have demonstrated maximum oscillation frequencies, fmm, of 158GHz and 135GHz, respectively [1,2]. Compared to the conventional surface channel MOSFET, Si/SiGe MODFETs have the potential to achieve better linearity and reduced noise due to a higher quality of the channelispacer interface.…”