Analytical Model for the Surrounded Field Plate in Folded Lateral MOSFET Structure

A novel unified analytical model concerning the surrounded plate field is proposed for extended drain MOSFETs (EDMOS) in this article for the first time. The SFP analytical model demonstrates the edge-assisted depletion (AD) effect and the multidimensional AD effect through the dielectric-layer (DL) potential function and 3-D Poisson equation. The closed-form solutions of the electric field and potential distributions are derived to predict the breakdown voltage (BV) for different SFP lengths and dielectric parameters. The 3-D electric field modulation effect brought on by SFP is presented. The impact of SFP parameters on BV is explained using the effective doping concentration (
${N}_{\text {deff}}{)}$
. The analytical model takes into account the multidimensional conduction path and the electron accumulation effect while determining the specific ON-resistance (
${R}_{\text {on},\textit {sp}}{)}$
of SFP EDMOS. The proposed model is useful for the trade-off between mobility and doping concentration. It can also analyze the impact of the strain on BV and
${R}_{\text {on},\textit {sp}}$
. The analytical model is validated by the good agreement between the modeling results and simulation results.