Design of Hafnium Oxide (HfO<sub>2</sub>) Sidewall in InGaAs/InP for High-Speed Electronic Devices

Abstract

The Indium Gallium Arsenide (InGaAs) based MOSFETs have been widely used in the research of high-speed devices with higher frequency. It has some application in the designing areas of power amplifiers. The InGaAs mainly have greater electron mobility and the lesser band gap in their compound makes them more suitable for developing high-speed devices. The Indium Gallium Arsenide compound-based MOSFETs are designed using the source/drain grown on a passive layer of Indium Phosphide substrate. This helps in reducing the power budget of the MOSFET and thereby reduces source and drain resistance. The re-grown layers over the bulk have serious issues such as parasitic capacitance and greater electrical field at the terminals of the gate along with the drain terminal. This results in a larger leakage current along with the terminals and thereby induces the degradation of the frequency of the application amplifiers. The high-ƙ dielectric along the gate terminal makes the device immune to leakage current for lesser frequency applications. The optimum material for the dielectric may be Hafnium (IV) Oxide – HfO2 which has been used as a sidewall in the proposed InGaAs MOSFET design. The device simulation was carried out in a way to evaluate the characteristics of the proposed designs. The results were submissive to the conventional MOSFETs in terms of output capacitance over the source and drain terminals, leakage current in the drain terminal, and improved frequency parameters. The results also suggested that the sidewall design over the gate terminal constitutes the frequency improvement without losing the power and current characteristics.