Correlation between hysteresis phenomena and hole-like trap in capacitance-voltage characteristics of AlGaN/GaN of Schottky barrier diode

¹ Laboratoire de Micro-Optoélectroniques et Nanostructures, Université de Monastir, Tunisia
² Institut d’Électronique de Microélectronique et de Nanotechnologie IEMN, Département hyperfréquences et Semiconducteurs, Université des Sciences et Technologies de Lille, France

^a e-mail: gassoumimalek@yahoo.fr

Received: 3 April 2011
Accepted: 13 May 2011
Published online: 18 August 2011

Abstract

In this work we report on the characteristics of (Ni/Au)/AlGaN/GaN/SiC Schottky barrier diode (SBD). A variety of electrical techniques such as capacitance-voltage (C-V) and deep-level transient spectroscopy (DLTS) measurements were used to characterize the diodes. We observed an hysteresis phenomenon on the C-V characteristics in the Schottky diode. The parasitic effect can be attributed to the presence of traps in the heterostructure. Deep defects analysis was performed by deep-level transient spectroscopy (DLTS). One hole trap have been detected with an activation energy and a capture cross-section of 0.75 eV and 1.093 × 10⁻¹¹ cm². The localization and the identification of this trap have occurred and a correlation between the defect and the hysteresis phenomenon has been discussed. At high temperatures, the DLTS signal sometimes becomes negative, likely due to an artificial surface-state effect.