Simulation analysis of a novel dual-trench structure for a high power silicon-on-insulator metal–semiconductor field effect transistor

In this paper, a silicon-on-insulator (SOI) metal–semiconductor field-effect transistor (MESFET) by a novel dual-trench technique is presented. In the proposed technique, the dual-trench is created in the buried oxide and filled with p-type and n-type doped Si. The p-type trench beneath the source increases breakdown voltage (VBR). Also, the n-type trench beneath the gate improves the drain current (ID). We call this new structure as Dual-Trench SOI MESFET (DT-MESFET). DC and radio frequency (RF) characteristics of the proposed structure are analyzed by 2-D numerical simulation and compared with conventional SOI MESFET (C-MESFET) characteristics. The extracted results show that the dual-trench technique has excellent effect on ID, VBR, and maximum output power density (Pmax) of the device. The parameters, VBR,ID, and Pmax of the DT-MESFET structure are improved by 55.55%, 50%, and 300% compared with those of the C-MESFET structure, respectively. Also, the dual-trench technique leads to the enhancement of maximum oscillation frequency and maximum available gain. Therefore, the novel SOI MESFET structure has superior electrical characteristics as compared to the similar device based on the conventional structure.