High Performance SON-LDMOS for RF Power Amplifier Application

A novel SON (silicon-on-nothing)-LDMOS (laterally diffused MOS) with heavily doped buried layer (HDBL) beneath air layer is proposed for RF base-station power amplifier application. The characteristics of the proposed device are analyzed in terms of breakdown voltage, kink effect, and high frequency performance. With the device and circuit simulator Atlas, two-dimensional simulations are presented to investigate the vertical and lateral breakdown voltages and parasitic capacitance characteristics of the proposed device. The simulation results show that high breakdown voltage and low parasitic output capacitance can be attained. The breakdown voltage of the proposed device is four times that of the conventional SOI (silicon-on-insulator) device. In addition, the kink effect and self-heating effect is suppressed dramatically. Our proposed device is fully compatible with commercial SON process, without complex field plate process. It can be used in the future design of high voltage RF power amplifiers.