A novel double field-plate power high electron mobility transistor based on AlGaN/GaN for performance improvement

In this paper, we have investigated the effectiveness of employing the drain field-plate technique to enhance the breakdown voltage of single source field-plate (SSFP) AlGaN/GaN power high electron mobility transistors (HEMTs). A systematic procedure is provided for designing this new double drain and source field-plate (DDSFP) structure, using two dimensional simulation to achieve the maximum improvement in the drain-source current (I_DS) and breakdown voltage (BV). It is found that significantly higher BV and I_DS can be achieved by just optimizing the thickness of the passivation layer Si₃N₄ beneath the field plates and the length of field plates connected to the source and drain. The effects of the substrate superjunction layers thickness and the gate recess depth on the BV are also studied.