Recessed p-buffer layer SiC MESFET: A novel device for improving DC and RF characteristics

Abstract

This is the first report of novel structures designated as recessed p-buffer (RPB) silicon carbide (SiC) metal semiconductor field effect transistors (MESFETs). Important parameters such as gate–source capacitance, short channel effect, DC trans-conductance, cut-off frequency, DC output conductance, drain current and breakdown voltage of the two structures, the source side-recessed p-buffer (SS-RPB) and drain side-recessed p-buffer (DS-RPB), are simulated and compared with the conventional recessed gate SiC MESFET. Our simulation results describe that reducing the channel thickness under the gate at the source side of the SS-RPB structure, improves the gate–source capacitance, DC trans-conductance, and cut-off frequency compared with DS-RPB and conventional structures. Short channel effects for the SS-RPB structure are improved compared with that of the DS-RPB structure. Also, the SS-RPB structure has smaller DC output conductance in comparison with the conventional and DS-RPB structures. However, saturated drain current and breakdown voltage in the DS-RPB structure is larger than those in the conventional and SS-RPB structures.