SOI LDMOS With High-k Multi-Fingers to Modulate the Electric Field Distributions

Abstract

The silicon-on-insulator (SOI) lateral double-diffused metal–oxide–semiconductor (LDMOS) with high- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{k}$</tex-math> </inline-formula> multi-fingers (HKMFs) is proposed and investigated. The fingertips are distributed at specific locations to modulate the electric field distributions and improve the device performances. First, the electric field peaks formed at the fingertips could optimize the electric field distributions, which improves the breakdown voltage (BV) of the LDMOS effectively. Meanwhile, the multi-fingers are embedded into the drift region to increase the optimal drift doping concentration, which facilitates the positive conduction of the device and reduces the specific ON-resistance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{R}_{\text{on,\text{sp}}}\text{)}$</tex-math> </inline-formula> . The simulation results show that the proposed HKMF-LDMOS with five multi-fingers increases the BV by 59.2%, reduces <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{R}_{\text{on,\text{sp}}}$</tex-math> </inline-formula> by 37.8%, and improves the figure of merit (FOM) by 4.07 times when compared to the conventional LDMOS.