The dual ion-implantation trench edge termination techniques were investigated and optimized using a two-dimensional device simulator. By trenching the field ring site which would be dual implanted, a better blocking capability can be obtained. The results show that the p-n junction with dual implanted junction field-ring can accomplish nearly 20% increase of breakdown voltage in comparison with the conventional trench field-rings. The fabrication is relatively difficult. But the trench etched field ring with dual ion-implantation is surpassed for breakdown voltage and consume same area and extensive device simulations as well as qualitative analysis confirm these conclusions.