Semi-numerical static model for nonplanar-drift lateral DMOS transistor

A semi-numerical static model for a nonplanar-drift lateral double-diffused MOS transistor (ND-LDMOST) is described. The modelling methodology is based on a regional approach, and its implicit equations are solved numerically. With the support of MEDICI simulations, a simplified quasi-two-dimensional analysis is used to characterize the nonplanar-drift region. The complete model is composite and accounts for LDMOST characteristics such as the doping-graded channel, the nonplanar-drift structure, and the space-charge-limited current flow in the drift region. The model equations are continuous on all operating bias conditions, which is especially important for convergence in the circuit simulator. The model predictions are in satisfactory agreement with experimental measurements. This ND-LDMOST model is suitable for incorporation into a SPICE-like circuit simulator.