OAM-RC

Abstract

The Au/n-GaN Schottky barrier diode (SBDs) has been characterized by current-voltage (I-V), capacitance-voltage (C-V) and deep level transient spectroscopy (DLTS) measurements in the temperature range of 85 K - 405 K. The estimated Schottky barrier height is 0.25 eV at 85 K and 1.06 at 405 K by I-V method, respectively. Calculations showed that the barrier height is 1.02 eV at room temperature by C-V method. Little variation with either temperature or frequency was observed, and the carrier concentration derived from these measurements confirmed the dopant concentration of ~ 6.2×1016 cm-3. A dominant trap Ea, with activation energy of 0.92 eV is observed in n-type GaN grown by metalorganic chemical vapor deposition (MOCVD). The capture cross section of 1.9×10-15 cm2 is estimated based on the well-known logarithmic dependence of DLTS peak height with different filling pulse width for trap Ea. The trap Ea (0.92 eV), which is commonly observed in thin GaN layer grown by various techniques, is believed to be associated with nitrogen interstitial defect.

Keywords

Au/n-GaN Schottky diode, Temperature-dependent electrical properties, Deep level defects, DLTS measurements.

Citation

P. KOTESWARA RAO, V. RAJAGOPAL REDDY, Temperature-dependent electrical properties of Au Schottky contact and deep level defects in n-type GaN, Optoelectronics and Advanced Materials - Rapid Communications, 2, 7, July 2008, pp.410-414 (2008).

Submitted at: April 29, 2008

Accepted at: July 8, 2008