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.

Recovery Performance of Ge-Doped Vertical GaN Schottky Barrier Diodes

“…During the t a period, the delay was strongly influenced by carrier trapping in the Schottky junction, while in the t b period, reverse recovery speed is also slowed by the time for sweeping the stored charge out of the junction. These results are consistent with our previous report [29], which suggested the RC time constant increases with the increase of device diameter and shows a good dependency with the reverse recovery time. And a further improvement of reverse recovery characteristics could be expected from a smaller electrode or thinner drift layer in these devices.…”

Vacancy-assisted core transformation and mobility modulation of a-type edge dislocations in wurtzite GaN

“…The nucleation and propagation of high density of threading dislocations are essential entities in the optoelectronic and protective coating applications of gallium nitride (GaN) and its compounds [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. It is well known that the dislocations in GaN can propagate along the epitaxial direction and annihilate in pairs and their density varies with increasing epitaxial layer thickness [15][16][17].…”