Change of high-voltage conduction mechanism in vertical GaN-on-GaN Schottky diodes at elevated temperatures

摘要

Current-voltage-temperature characteristics (0 degrees C to 150 degrees C) of SBDs on highly compensated 15 mu m and 30 mu m n-type GaN drift layer were measured for voltages up to -300 V and up to -800 V, respectively. When the temperature is between 75 degrees C and 100 degrees C, both SBDs exhibited a similar change in conduction mechanism from thermionic field emission (TFE) to thermionic emission (TE) due to the activation of N-vacancies (V-N) (E-a = -1.67 0.02 eV). However, at high voltages when the temperature is 100 degrees C, the conduction mechanism changes from TE to TFE due to the de-trapping of electrons from activated carbon-traps (E-a = +0.69 eV) in the grown drift layers.