Breakdown Ruggedness of Quasi-Vertical GaN-Based p-i-n Diodes on Si Substrates

This letter reports the breakdown ruggedness of GaN-based quasi-vertical p-i-n diodes on Si for the first time. With a 2μm-thick drift layer, the 0.08-mm2devices can sustain a surge current up to 0.73 A, and maximum sink in energy of 3 mJ using an unclamped inductive switching test setup. No parametric drift nor device degradation was found after repetitive avalanche test consisting of multiple 50 000 breakdown events with a frequency of 1 kHz. At elevated temperatures, the breakdown voltage exhibits little temperature dependence, which could be explained by a trap-assisted space-charge-limited current conduction mechanism. With good ruggedness quality under repetitive test and at elevated temperatures, the quasi-vertical GaN p-i-n diodes on Si show great potential in achieving cost-effective rectifiers for high-voltage applications.