Recovery Characteristics Of Silicon-based Power Diode

The P-I-N diode was briefly introduced. The forward recovery, theforward conduction and the reverse recovery of P-I-N diode for4H-SiCwere studied by MATLAB simulation. Some meaningful results wereobtained. The details were listed below:Firstly, the superior performances of SiC, including the value of theband-gap, the intrinsic carrier concentration, the low-field mobility, theionization grade and the band-gap narrowing, were discussed.Secondly, according to the Lumped-Charge model, the forwardrecovery of4H-SiC P+-N-(P-)-N+diode was analyzed. The infections andforward power loss were discussed. The conclusion showed that: thedoping density, width and temperature have apparent influence on theforward overshoot voltage. The forward recovery energy loss cannot beneglected in the future high-power diode.Thirdly, by applying the Bellone’s model, the effect of width anddoping concentration on the forward conduction current-voltagewaveforms were researched. The current-voltage waveform of theP+-P--N+structure was compared with the P+-N--N+structure’s. The resultsreveal that, under the same voltage, the4H-SiC P+-N--N+diodecurrent-voltage characteristics are more superior than the4H-SiCP+-P--N+diode’s.Lastly based on the Lumped-Charge model, the reverse recovery of4H-SiC P+-N-(P-)-N+diode was studied. The influence of the decrease rateof current, the temperature, the base parameters on the reverse recoverycurrent waveforms were analyzed. By compare the p type with the n type,we found, because of the different carrier mobility, the p type’s reverserecovery time is shorter than n type’s.