Investigation of the reverse recovery characteristics of vertical bulk GaN-based Schottky rectifiers

Abstract

The reverse recovery characteristics of vertical bulk GaN-based Schottky rectifiers, which were fabricated on free-standing GaN substrates, were systematically investigated. The corrected reverse recovery time was obtained to be about 13.4 ns, 41.0 ns and 81.2 ns for 1 mm, 2 mm, and 3 mm diameter Schottky diodes, respectively. The dominant factor that affects the reverse recovery time of a bulk GaN-based Schottky rectifier was found to be the RC time constant, which was the product of the circuit resistance and capacitance. Besides that, the reverse recovery characteristics of the bulk GaN-based Schottky rectifiers at different temperatures were also measured and analyzed. It was found that the reverse recovery time of the bulk GaN-based Schottky diodes was less influenced by temperature, since the intrinsic exitation in the wide bandgap semiconductor of GaN was almost not influenced by temperature.