Editors' Choice-Thin Film Transistor Response in the THz Range

Novel metal oxide materials such as InGaZnO (IGZO), ZnO, SnO, and In2O3 and improved fabrication processes dramatically enhanced the achieved and projected thin film transistor (TFT) performance. The record values of the effective field-effect mobility of Metal Oxide TFT (MOTFT) materials have approached 150 cm(2)/Vs. We report on an improved compact TFT model based on three models: the RPI TFT model, the unified charge control model (UCCM), and the multi-segment TFT compact model. This improved model accounts for a non-exponential slope in the subthreshold regime by introducing a varying subthreshold slope and accounts for non-trivial capacitance dependence on the gate bias, and parasitic impedances. The analysis of the TFT response using this model and the analytical calculations showed that TFTs could have a significant response to impinging THz and sub-THz radiation. Using a complementary inverter and the phase-matched THz signal feeding significantly improves the detection sensitivity.

Automated summary

Novel metal oxide materials and improved fabrication processes have significantly enhanced the performance of thin film transistor (TFT), with approaches of 150 cm²/Vs in the effective field-effect mobility. An improved compact TFT model based on three models has been reported in this study, which considers the non-exponential slope in the subthreshold regime and the non-trivial capacitance dependence on gate bias. The TFTs have shown a substantial response to impinging THz and sub-THz radiation, and the detection sensitivity can be improved by using a complementary inverter and phase-matched THz signal feeding.