Current transport mechanisms and trap state investigations in (Ni/Au)-AlN/GaN Schottky barrier diodes
Author
Arslan, E.
Bütün, S.
Şafak, Y.
Çakmak, H.
Yu, H.
Özbay, Ekmel
Date
2010-10-13Source Title
Microelectronics Reliability
Print ISSN
0026-2714
Publisher
Elsevier
Volume
51
Issue
3
Pages
576 - 580
Language
English
Type
ArticleItem Usage Stats
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Abstract
The current transport mechanisms in (Ni/Au)-AlN/GaN Schottky barrier diodes (SBDs) were investigated by the use of current-voltage characteristics in the temperature range of 80-380 K. In order to determine the true current transport mechanisms for (Ni/Au)-AlN/GaN SBDs, by taking the Js(tunnel), E 0, and Rs as adjustable fit parameters, the experimental J-V data were fitted to the analytical expressions given for the current transport mechanisms in a wide range of applied biases and at different temperatures. Fitting results show the weak temperature dependent behavior in the saturation current and the temperature independent behavior of the tunneling parameters in this temperature range. Therefore, it has been concluded that the mechanism of charge transport in (Ni/Au)-AlN/GaN SBDs, along the dislocations intersecting the space charge region, is performed by tunneling. In addition, in order to analyze the trapping effects in (Ni/Au)-AlN/GaN SBDs, the capacitance-voltage (C-V) and conductance-voltage (G/ω-V) characteristics were measured in the frequency range 0.7-50 kHz. A detailed analysis of the frequency-dependent capacitance and conductance data was performed, assuming the models in which traps are located at the heterojunction interface. The density (Dt) and time constants (τt) of the trap states have been determined as a function of energy separation from the conduction-band edge (Ec - Et) as Dt≅ (5-8)×10 12eV-1 cm-2andτt≅(43-102) μs, respectively.
Keywords
Analytical expressionsApplied bias
Capacitance voltage
Charge transport
Conduction band edge
Current transport mechanism
Energy separations
Fit parameters
Fitting results
Frequency ranges
Frequency-dependent capacitance
Heterojunction interfaces
Saturation current
Space charge regions
Temperature dependent behavior
Temperature range
Time constants
Trap state
Trapping effects
Tunneling parameter
Capacitance
Heterojunctions
Schottky barrier diodes
Current voltage characteristics