Semiconductor thickness and back-gate voltage effects on the gate tunnel current in the MOS/SOI system with an ultrathin oxide

The effects of the semiconductor layer thickness and the back-gate voltage on the current-voltage (I-V) characteristics of the MOS/SOI tunnel diode with an aluminum gate and n-type semiconductor layers are theoretically investigated. If the semiconductor thickness is reduced or the back-gate voltage is more negative, the total thermal generation current decreases and the gate-oxide thickness critical for transition from the quasiequilibrium strong inversion state to the nonequilibrium state increases. If the MOS/SOI tunnel diode is in the transition range between the nonequilibrium and quasiequilibrium states, a positive increase of the back-gate voltage V_BG results in a strong increase of the majority carrier tunnel current. This back-gate effect may be exploited in more functional devices based on the MOS/SOI tunnel diode.