Analytical investigation of short-channel effects in retrograde double quan
tum well Si1-xGex-channel p-MOSFETs with effective channel lengths in the d
eep-submicron regime is addressed. The short-channel effects are accounted
for by treating the short-channel device as a long-channel one with an appa
rently-reduced doping density which depends on the channel length and the g
ate/drain bias. The analysis focuses on the threshold voltage reduction, th
e gate voltage window, and the hole densities in the quantum wells. The mod
el predicts significant differences in the threshold voltage reduction in t
he different channels of the device. The reduction is negligible in the sur
face parasitic channel, fairly small in the second quantum well (channel 2)
below the surface channel, and relatively pronounced in the first quantum
well closer to the depletion region (channel 1). Accordingly, the gate volt
age window increases significantly. The hole density in the different chann
els has also been found to be appreciably influenced by decreasing channel
length. The validity of the model is confirmed by comparing analytical calc
ulations with available experimental and numerical results. These investiga
tions can be used as guidelines for scaling Si/Si1-xGex devices as they ill
ustrate the degrees of freedom available to the Si/Si1-xGex MOSFET designer
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