Demonstration of Pseudo Independent Driving of Buried Gate in Trench Field Plate MOSFETs

We have proposed pseudo independent driving technique of Gate and buried Field Plate (FP) gate in a Trench Field Plate Power MOSFET (Trench FP MOSFET). Proposed method is expected to low conduction loss due to biased buried FP gate as well as a Gate-connected buried FP gate (Gate FP) and high-speed switching as well as a Source-connected buried FP gate (Source FP) by using only three additional components and this module behaves like a conventional three-terminal power MOSFET. In this paper, we experimentally demonstrated static characteristics and dynamic switching performances of this pseudo independent driving. We fabricated proposed pseudo driving module with discrete components on DBC (Direct Bonded Copper) substrate. Breakdown voltage and diode characteristics of this module were comparable to the Source FP and the Gate FP. On-resistance of this module was lower than the Source FP and the same as the Gate FP. Turn-on and turn-off period of this module became shorter than the Gate FP and were almost comparable to the Source FP.