The role of quantization effects on the operation of 50 nm MOSFET and 250 nm FIBMOS devices

We investigate quantum mechanical space quantization effects in conventional MOSFET devices and asymmetric device structure fabricated via focused ion beam technique (FIBMOS device). We find that the inclusion of the quantum mechanical space-quantization effects along the growth direction gives rise to larger average displacement of the carriers from the semiconductor-oxide interface and reduced sheet electron density. This, in turn, leads to threshold voltage shift on the order of 150 to 200 mV, which affects the magnitude of the on-state current and gives rise to transconductance degradation.