An Effective Method to Compensate Total Ionizing Dose-Induced Degradation on Double-SOI Structure

The existence of buried oxide (BOX) layer and the strong coupling effect between the front and back channels can worsen the radiation-induced degradation on fully depleted silicon-on-insulator (FDSOI) device. To mitigate the radiation impact, a new structure named double SOI is introduced in this paper. This new structure exhibits potential benefits of reducing the radiation-induced degradation effectively and independently, thanks to the additional electrode, which can be used to control the internal electrical field of the BOX layer. With this structure, FDSOI device parameter degradation due to total dose is studied, and some abnormal phenomena, such as the transconductance hump and the mobility enhancement, are observed and discussed. Sentaurus TCAD simulations are used for further analysis. Moreover, the impact of negative back-gate bias to transistor parameter degradation is investigated, and an improved back-gate compensation strategy is proposed. Technology improvement such as thinning the BOX on total ionizing dose (TID) amelioration is also discussed with TCAD simulation.