Trap analysis on Pt-AlGaN/GaN Schottky barrier diode through deep level transient spectroscopy

Abstract

Trap characterization on GaN Schottky barrier diodes (SBDs) has been carried out using deep-level transient spectroscopy (DLTS). Selective probing by varying the ratio of the rate window values (r) incites different trap signatures at similar temperature regimes. Electron traps are found to be within the values: 0.05–1.2 eV from the conduction band edge whereas the hole traps 1.37–2.66 eV from the valence band edge on the SBDs. In the lower temperature regime, the deeper electron traps contribute to the capacitance transients with increasing r values, whereas at the higher temperatures >300 K, a slow variation of the trap levels (both electrons and holes) is observed when r is varied. These traps are found to be mainly contributed to dislocations, interfaces, and vacancies within the structure.