Hall mobility measurement in double-gate SOI MOSFETs

Double-gate SOI MOSFETs such as gate-all-around (GAA) (Colinge, 1997) or delta (Hisamoto et al., 1991) structures are considered as strong candidate structures for ultimate ultra-short MOSFETs. These devices benefit from remarkable advantages such as increased drain current, ideal subthreshold swing, reduced short-channel effect and low leakage currents. GAA transistors introduce the concept of volume inversion (Balestra et al., 1987) in which the minority carriers are no longer confined at the interfaces but spread out across the silicon film. The main benefit is the gain in transconductance due to electron transport with volume-like mobility. So far, no direct measurement of mobility in double-gate devices has been reported. In this paper, the electron mobility is extracted from Hall effect measurements, on special double-gate structures, at 300 K and 77 K. This method is also compared to conventional techniques for mobility extraction based on transistor characteristics