Dislocation defect based model analysis for the pre-breakdown reverse characteristics of 4H–SiC p+n diodes

A model analysis of the reverse characteristics of 4H–silicon carbide diodes in the pre-breakdown regime is carried out to probe the physics and qualitative trends arising from the presence of dislocations and traps in the material. Results compare favorably with recent data. The response is shown to be controlled primarily by the impact ionization process. With dislocation defects, significant increases in the device current, a softer threshold and lower hold-off capabilities are predicted in keeping with measurements.