High Performance SEB Hardened Trench Power MOSFET with Partially Widened Split Gate and Trench Source

In this paper, an optimized trench power MOSFET is presented with three-dimensional (3D) TCAD simulation. A superior device’s performance can be achieved by using the partially widened split gate and the trench source. Simulation results indicate that the new structure can present a good static parameters and a better $R_{DS(\mathrm{ON})} {\times} \mathrm{Q}_{\mathrm{CD}}$ FOM compared with the conventional structure. Moreover, the proposed structure shows no SEB under the device’s rated breakdown voltage and the LET value of 1pC/$\mu$m $\left(100 \mathrm{MeV} \cdot \mathrm{cm}^{2} \cdot \mathrm{mg}^{-1}\right.$, approximately the maximum LET energy of gold or bismuth ion). That means, the proposed structure will not exhibit SEB under heavy ions. Therefore, the new structure demonstrates a good electrical parameter and a superior SEB SOA simultaneously.