SOI SJ high voltage device with linear variable doping interface thin silicon layer

Abstract

A novel high concentration linear variable doping interface thin silicon layer (TSL) silicon-on-insulator (SOI) super junction (SJ) LDMOS is proposed. The design of the linear variable doping can deplete the high drift concentration. The proposed structure uses a TSL to achieve charge balance and eliminate substrate-assisted depletion effect. The dielectric electric field (EI) and the breakdown voltage (BV) of the TSL SOI SJ are 530 V/μm and 552 V with 30 µm length drift region and 1 µm-thick dielectric layer, respectively, and the specific on-resistance (Ron, sp) is 0.03403 Ω·cm2 and FOM (FOM=BV2/Ron,sp) is 8.95 MW/cm2, when gate voltage is 5 V.