Impact of BOX/substrate interface on low frequency noise in FD-SOI devices

The impact of carrier trapping at the substrate/buried oxide interface on the LF noise characteristics of Fully Depleted MOSFETs has been calculated. The channel LF noise analysis based on carrier number fluctuation approach has been extended to include charge variations at the substrate/buried oxide interface. The impact of fluctuations of substrate/BOX interfacial charge on the channel drain current has thereby been studied as a function of gate bias. The results suggest that substrate doping concentration, buried oxide thickness and dielectric material have non-negligible effect on the contribution of the substrate interface noise to the total device noise. To our knowledge, the contribution of this noise to the total noise of a FD-SOI device has never been studied.