Non-Linear Coupling Effects in Fully Depleted SOI Transistors

Experimental results show the response of 22 nm fully depleted silicon on insulator (FDSOI) transistors to 10 keV x-rays. The extracted coupling factor between the front- and back-gates of the device shows a divergence from the traditionally assumed coupling factor exhibiting a non-linear dependence on total ionizing dose (TID). A depletion region in the well under the buried oxide is included in the model of the device. The coupling factor is rederived using the new model following the previous derivation. The new coupling factor has a dependence on TID received by the device. Verification of the new model is performed with comparisons to the experimental data and technology computer-aided design (TCAD) simulations. The new model fits well to data and simulations.