Dependence of breakdown voltage on drift length and linear doping gradients in SOI RESURF LDMOS devices

An optimal variation in lateral doping profiles is proposed for the drift region of lateral power devices in partial SOI technology in order to achieve breakdown voltage above 200 V for both off-state and on-state operations. LDMOS structure incorporating the proposed optimal doping profile are analyzed for their electrical characteristics and compared with conventional uniformly doped partial SOI and thin layer SOI by extensive 2D numerical simulations using MEDICI. The results indicate that the proposed optimal doping profile is in good agreement with the optimal doping gradient for JI technology. The optimal doping profile can significantly improve the trade-off between breakdown voltage and specific on-resistance in comparison to uniformly doped P-SOI.