4H-SiC-Dopant Segregated Schottky Barrier Cylindrical Gate All Around MOSFET for high speed and high power microwave applications

This paper presents extensive study of proposed 4H-Silicon Carbide (SiC) based Dopant Segregated (DS) Schottky Barrier (SB) Cylindrical Gate All Around (CGAA) MOSFET with high-k gate dielectric for hostile environment such as high temperature and radiation exposure for high power microwave applications. The Analog/RF performance of SiC-CGAA has been investigated by exploiting temperature variation from 300 K to 500 K, along with the leverage of Schottky-Barrier (SB) Source/Drain and Dopant Segregation (DS). DS is primarily used to reduce the ambipolar behavior of SB MOSFET and boost the performance of the device. Analog/RF performance in terms of main figure of merits like Ion/Ioff, transconductance (gm), Early Voltage, Stern Stability Factor (K), cut-off frequency (ft) has been carried out using ATLAS-3D device simulator.

I. Introduction

Ultra scaled Silicon based MOS device requires a smarter cooling system that can assure a longer life to the device but in some cases air cooling is not viable. Silicon Carbide (SiC) is a nostrum semiconductor material with wide energy band gap , for solid-state electronic devices at elevated temperature owing to its excellent electrical and mechanical properties. It gained enormous attraction because of its inherent material advantages e.g. high temperature, high power, high frequency, radiation hardened applications. The semiconductor devices are exposed to very high range of temperature variations when used in the area of space explorations, the geothermal and mining exploration, hybrid electric vehicles (HEV), nuclear power plant, aircraft industries, aeronautics application and industrial process control [1]–[2]. SiC based metal-semiconductor FET has become an advantageous technology for high-power microwave applications, such as the transmitters for the commercial and military communications [3]. SiC is prevailing wide band gap material with variety of features like high electric breakdown field (3.5 × 10⁶ V/cm), high electron saturation drift velocity (2.0 × 10⁷ cm/s), high melting point (2830 °C) and high thermal conductivity (4.9 W/cmK) [1].