Current-voltage characteristics of (Mo/Au)/AlGaN/GaN/Si Schottky diodes
Résumé
The AlGaN/GaN high electron mobility transistors (HEMTs) is a promising candidate for microwave applications due to its high power and high temperature. owing to their large and direct band gap, as well as favorable transport properties. Moreover, III-V nitrides could be suitable for the emitters and detectors of green and shorter wavelengths, in turn making investments in this class of materials more than worthwhile. The electrical characteristics of metal contactst on-GaN have been examined by numerous research groups. The mechanism of leakage currents through GaN and AlGaN Schottky interfaces is discussed using temperature- dependent current-voltage (I-V-T) measurements, and found that the barrier thinning caused by unintentional surface-defect donors enhances the tunneling transport processes, leading to large leakage currents through GaN and AlGaN Schottky interfaces. Key world: AlGaN/GaN, HEMTs, I-V, Schottky barrier height, Barrier inhomogeneity.