A novel high frequency and high breakdown voltage SOI MESFET by modified DC and radio frequency characteristics

In this paper, a novel silicon-on-insulator (SOI) metal–semiconductor field-effect transistor (MESFET) with modified charge distribution is proposed. Charge distribution changing goes to lower electric field crowding and increased breakdown voltage (VBR). For modifying charge distribution, additional region of silicon (RS) with doping level > 1020 cm−3 is utilized in buried oxide of the SOI MESFET. In order to achieve the best results, the RS location and dimensions are optimized carefully. DC and radio frequency characteristics of the SOI MESFET with RS (RS-SOI MESFET) are analyzed by 2-D numerical simulation and compared with conventional SOI MESFET (C-SOI MESFET) characteristics. The simulation results show that the RS has excellent effects on the breakdown voltage of the device, which increases by 333.33% compared with that of the conventional SOI MESFET structure. Also, drain current of the proposed structure increase slightly and the maximum output power density improves by 305.88%. In addition, the RS causes the improvement of the device gains and frequency parameters. Consequently, the novel SOI MESFET structure has superior electrical characteristics for high-power and high-speed applications compared with the similar device based on the conventional structure.