Effects of drift region parameters on the static properties of power LDMOST

The effects of the drift region geometry and the physical parameters on the thin layer (resurfed) lateral DMOS transistor operation have been studied for both the static on-state and the off-state. The variations of breakdown voltage with drift region parameters were investigated using numerical modeling and compared to the experimental results. The operation of the LDMOST in the on-channel condition was modeled semi-empirically. The analytical and experimental results show that the operation of the device depends strongly on the geometry and the physical parameters of the drift region, particularly at high gate voltages and low drain voltages. Design guidelines for the lateral DMOS transistor for switching applications are discussed.