Low-temperature electron mobility in Trigate SOI MOSFETs

Evidence of one-dimensional subband formation is found at low temperature in trigate silicon-on-insulator MOSFETs, resulting in oscillations of the I/sub D/(V/sub G/) characteristics. These oscillations correspond to the filling of energy subbands by electrons as the gate voltage is increased. High mobility, reaching 1200 cm/sup 2//Vs, is measured in the subbands at T=4.4 K. Subband mobility decreases as temperature is increased. Conduction in subbands disappears for temperatures higher than 100 K or for drain voltage values that are significantly larger than kT/q.