A Special Total-Ionizing-Dose-Induced Short Channel Effect in Thin-Film PDSOI Technology: Phenomena, Analyses, and Models

A special total-ionizing-dose-induced short channel effect in thin-film partially depleted silicon-on-insulator (PDSOI) technology is found. Short devices suffer more significant total-ionizing-dose-induced threshold voltage shift of the front-gate main transistor. The devices under pass-gate (PG) bias show worse threshold voltage shift of the front-gate main transistor than the devices under ON bias, which reveal that the trapped charges in the buried oxide layer are more responsible for these phenomena. Through the simulation of the electric field under PG bias by TCAD, we found that devices with different lengths can be uniformly divided into four regions. Then we combined the partially full depletion model with charge-sharing model and made a qualitative analysis of this effect. On this basis, we proposed a quantitative analysis model. Through this model, we can calculate the threshold voltage shift of the front-gate main transistor through the threshold voltage shift of back-gate main transistor.