The need of continue scaling, mobile and IoT applications has increased the demand for the devices of low supply voltage and low-leakage operations. Tunnel field effect transistors (TFETs) have potential to overcome the fundamental sub-threshold limitation of 60 m V/dec limit of the traditional metal-oxide-semiconductor field effect transistor (MOSFET). The TFET has been proposed as replacement for the MOSFET while the fundamental power issue faced by the traditional MOSFET as device scaling continues the demand of Moore’s law. The TFET is the promising option as an emerging transistor for further scaling down the supply voltage, threshold voltage and power consumption of integrated circuits (ICs).
In this thesis the effect of gate oxide scaling on the MOSFET and TFET is investigated. We have simulated MOSFETs and TFETs with different equivalent-oxide-thickness (EOT), using Sentaurus TCAD. The comparison of obtained results shows that EOT scaling influences the electrical characteristics of a TFET more significantly, and a thinner EOT improves the devices performance in terms of a higher on-current and steeper subthreshold slope. EOT scaling has less effect on the MOSFET devices performance. The simulation results were also compared to experimental results, and they were in a good agreement.

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