A novel high-performance SOI MESFET by stopping the depletion region extension

A novel power SOI-MESFET is proposed which consists of an insulator region in the channel for high-power applications. The key idea in this work is to stop the depletion region extension toward the drain and source regions and eliminate the gate adjacent spaces. We called the proposed structure as stopped depletion region extension SOI (SDR-SOI) MESFET. The breakdown voltage (VBR) and small-signal characteristics of the proposed structure improve due to the high critical electric field of the insulator region and less extended depletion region. The optimized results show that the VBR of the SDR-SOI MESFET is 45% larger than that obtained for the conventional SOI MESFET (C-MESFET). Furthermore the maximum output power density of the SDR-SOI MESFET is 0.33 W/mm compared with 0.24 W/mm of the C-MESFET. Meanwhile the elimination of the gate depletion layer extension to source/drain leads to decrease gate–drain capacitance (CGD). So, the proposed structure presents the potential for high-power applications.