Superior performance in double-diffused MOSFET by multi-trench gate structure: physical investigation and design

Abstract

The Double-diffused Metal-Oxide-Semiconductor (D-MOSFET) is the first Power MOSFET structure to be widely used across an extensive range of power levels. This article describes a physical investigation and design of D-MOSFET construction with superior performance. We introduce a groundbreaking exploration into the design of trench gates within U-shaped double-diffused MOSFETs (UDMOSFETs), focusing on Baliga’s figure of merit (BFOM). The findings provide valuable insights for advancing power semiconductor devices, underscoring the importance of trench gate technology in optimizing device performance. The BFOM reaches its peak when the doping concentration of the drift region (NDrift) is 6 × 1016 cm−3 with an indication of almost 40% improvement in MTG-UDMOSFET (M = 4) compared to C-UDMOSFET. Furthermore, within the optimum values of NDrift, length of the drift region, and depth of trench gate, the on-resistance in MTG-UDMOSFET (M = 4) experiences a 46% reduction compared to the conventional structure.