On-Resistance Model for VDMOS

On-resistance is one of important parameters for VDMOS,and it is an important index to improve on-off efficiency and reduce power waste of VDMOS.By using basic physical equation of semiconductor,such as Poisson equation,a new method to establish an exact on-resistance model based on the physical structure of VDMOS device was given.Neck block is modeled with arc boundary.By reviewing carrier moving law,solving Poisson equations,and uniting device structure and boundary conditions,epitaxy block is modeled.This method has clear physics conception,evades experience parameters,and considers the effect of structure parameters to on-resistance.The model agrees with the results simulated by MEDICI.