Reverse-bias leakage current reduction in GaN Schottky diodes by electrochemical surface treatment
نویسندگان
چکیده
An electrochemical surface treatment has been developed that decreases the reverse-bias leakage current in Schottky diodes fabricated on GaN grown by molecular-beam epitaxy ~MBE!. This treatment suppresses current flow through localized leakage paths present in MBE-grown GaN, while leaving other diode characteristics, such as the Schottky barrier height, largely unaffected. A reduction in leakage current of three orders of magnitude was observed for Schottky diodes fabricated on the modified surface compared to diodes fabricated on the unmodified surface for reverse-bias voltages as large as 220 V. In addition to suppressing reverse-bias leakage, the surface treatment was found to improve substantially the ideality factor of the modified surface diodes compared to that of unmodified surface diodes, suggesting that such a surface modification process could be useful for a variety of GaN-based electronic devices. © 2003 American Institute of Physics. @DOI: 10.1063/1.1554484#
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