Dynamic punch-through design of high-voltage diode for suppression of waveform oscillation and switching loss

The authors analyzed the surge voltage causing the oscillation in detail and found that the peak electric field at punch-through E_P is proportional to the maximum surge voltage. The maximum surge voltage can be decreased by shifting the punch-through position W_P toward the cathode side because the W_P shift leads E_P lowering. This dynamic punch-through design is applicable for whole operating condition. Based on the above discussions, a PIN-diode with a novel structure was invented that achieves the ideal carrier profile for shifting the W_P closer to the cathode side with high electron injection during low-current operation. The simulation results show the maximum surge voltage causing oscillation was suppressed to about 50% lower and the switching loss of the diode also decreased to about 60% lower in the same time compared with the conventional structure.