Recovery Performance of Ge-Doped Vertical GaN Schottky Barrier Diodes

Vertical GaN Schottky barrier diodes (SBDs) were fabricated on Ge-doped free-standing GaN substrates. The crystal quality of the SBDs was characterized by cathode luminescence measurement, and the dislocation density was determined to be similar to 1.3x10(6)cm(-2). With the electrical performance measurements conducted, the SBDs show a low turn-on voltage V-on (0.70 similar to 0.78V) and high current I-on/I-off ratio (9.9x10(7)similar to 1.3x10(10)). The reverse recovery characteristics were investigated. The reverse recovery time was obtained to be 15.8, 16.2, 18.1, 21.22, and 24.5ns for the 100-, 200-, 300-, 400-, and 500-m-diameter SBDs, respectively. Meanwhile, the reverse recovery time and reverse recovery charge both show a significant positive correlation with the electrode area.