Comparison of reverse current mechanisms in GaN Schottky diodes grown on sapphire versus ammonothermal GaN substrates
Open Access
- 11 March 2026
- journal article
- Published by IOP Publishing in Journal of Physics D: Applied Physics
- Vol. 59 (12)
Abstract
In this work, we analyse the reverse current mechanisms in GaN Schottky barrier diodes (SBDs) grown on sapphire and native GaN substrates. For the sapphire-substrate sample, two conduction mechanisms are identified: Poole-Frenkel emission (PFE) and trap-assisted tunneling (TAT), with corresponding trap energy levels of 0.9 eV and 0.29 eV, respectively. In contrast, only PFE is observed in the GaN-substrate sample, with a trap energy of 0.75 eV, suggesting that the presence of TAT is related to the higher dislocation density in structures grown on sapphire substrates. The leakage mechanisms and associated trap energies are extracted by comparing experimental current-voltage (I-V) characteristics with a model that includes thermionic emission and tunneling contributions for different temperatures, from 298K up to 443K.Keywords
Funding Information
- French network Renatech
- Chips Joint Undertaking
- Equipex+ Nanofutur
- PEPR Electronique
This publication has 24 references indexed in Scilit:
- Electrical Characteristics of an Ag/n-InP Schottky Diode Based on Temperature-Dependent Current–Voltage and Capacitance–Voltage MeasurementsMetallurgical and Materials Transactions A, 2015
- Temperature dependence of current-and capacitance–voltage characteristics of an Au/4H-SiC Schottky diodeSuperlattices and Microstructures, 2014
- Analysis of electrical properties and deep level defects in undoped GaN Schottky barrier diodeThin Solid Films, 2013
- Temperature dependence of reverse-bias leakage current in GaN Schottky diodes as a consequence of phonon-assisted tunnelingJournal of Applied Physics, 2006
- Deep levels in high resistivity GaN epilayers grown by MOCVDphysica status solidi (c), 2006
- Leakage mechanism in GaN and AlGaN Schottky interfacesApplied Physics Letters, 2004
- Analysis of reverse-bias leakage current mechanisms in GaN grown by molecular-beam epitaxyApplied Physics Letters, 2004
- Study of electrically active defects in n-GaN layerMaterials Science in Semiconductor Processing, 2001
- A new method of reducing dislocation density in GaN layer grown on sapphire substrate by MOVPEJournal of Crystal Growth, 2000
- Barrier inhomogeneities at Schottky contactsJournal of Applied Physics, 1991