A New Semi-SJMOS for Improving the Reverse Recovery Soft and Dynamic Avalanche of the Body Diode

A novel Semi-SJMOS with a n 1 n 2 p 1 n 3 bottom assist layer that has gradually varied epitaxial doping concentration is proposed in this paper. During the reverse recovery process of the body diode, due to the introduction of p 1 region, holes will be injected, which reduces the extraction of the carrier, makes the body diode have a soft reverse recovery characteristic and suppresses the peak voltage of reverse recovery. The simulation results show that the peak electric field at the p1n3 junction of the novel structure is decreased and the softness factor is increased by 48% compared to the conventional structure. The ruggedness of the body diode dynamic avalanche has been significantly improved.