Numerical analysis of silicon-on-lnsulator short channel effects in a radiation environment

Radiation-induced charge build-up in the buried oxide (BOX) of SOI MOSFETs affects device performance through threshold voltage shifts of the back channel. This charge build-up is related to the electric field in the BOX during irradiation. In this paper, we report on the application of a numerical model for the potential distribution in a semiconductor device to the task of determining the electric field in the BOX. This electric field distribution is then combined with a model for charge accumulation as a function of electric field during irradiation to predict the threshold voltage shifts in the back channel of SOI MOSFET devices as a function of channel length. For the device design analyzed here, this model agrees with available experimental data and predicts an increase in back channel threshold shift as the channel length enters the sub-micron regime.