Raised breakdown voltage in a high‐voltage recessed LDD‐SOI by submerged SI3N4

A new structure of metal‐oxide‐semiconductor field‐effect transistors (MOSFETs) with lateral double‐diffused MOSFET was introduced based on the silicon‐on‐insulator lightly doped‐drain metal‐oxide‐semiconductor field‐effect‐transistor (SOI‐LDD MOSFET) technology, called recessed silicon nitride lateral‐double diffused silicon‐on‐insulator (RS‐LDD SOI). In the proposed structure, a recession was created on the buried oxide layer and filled with a silicon nitride (SI3N4) layer. Silicon nitride makes the electric field distribution more uniform by modulating the electric field in the drift zone, thereby increasing the breakdown voltage of the proposed structure. The simulation results performed with ATLAS software demonstrated the performance improvement of the proposed structure. Increasing the breakdown voltage by 31% compared to the conventional structure was one of the most important achievements of this work. Also, design considerations were made on the submerged part in the buried oxide, which can be an excellent guide to achieving the optimal performance of the proposed structure.