Multi-dimensional accumulation gate LDMOS with ultra-low specific on-resistance

Abstract

A novel multi-dimensional accumulation gate (MDAG) lateral double-diffused MOS (LDMOS) with ultra-low specific on-resistance (Ron,sp) is proposed and investigated by simulation. The MDAG LDMOS is composed of the MDAG, the trench source, and the N-Buffer. In the on-state, the bulk electron channels are formed in the P-well and the multi-dimensional electron layers are formed in the drift region. Meanwhile, the trench source shortens the current path length. Thus, the Ron,sp is greatly reduced. In the off-state, the N-Buffer is used to form a PN junction with the P-Substrate to obtain the ideal reverse characteristics of the accumulation model LDMOS, and thus the high breakdown voltage (BV) is achieved. The simulation results show that the proposed MDAG LDMOS has a Ron,sp of 0.33 mΩ cm2 and a BV of 181.4 V. The figure of merit (FOM) is as high as 99.7 MW/cm2. Hence, the tradeoff between Ron,sp and BV is greatly improved, and the silicon limit of RESURF is broken.