open access

https://hdl.handle.net/2115/67320

Highly-stable and low-state-density Al2O3/GaN interfaces using epitaxial n-GaN layers grown on free-standing GaN substrates

英語

2016-10-18

American Institute of Physics (AIP)

Applied physics letters

109(16)

162104-1-162104-5

Interface characterization was carried out on Al2O3/GaN structures using epitaxial n-GaN layers grown on free-standing GaN substrates with relatively low dislocation density (<3 x 10(6) cm(-2)). The Al2O3 layer was prepared by atomic layer deposition. The as-deposited metal-oxide-semiconductor (MOS) sample showed a significant frequency dispersion and a bump-like feature in capacitance-voltage (C-V) curves at reverse bias, showing high-density interface states in the range of 10(12) cm(-1) eV(-1). On the other hand, excellent C-V characteristics with negligible frequency dispersion were observed from the MOS sample after annealing under a reverse bias at 300 degrees C in air for 3 h. The reverse-bias-annealed sample showed state densities less than 1 x 10(11) cm(-1) eV(-1) and small shifts of flat-band voltage. In addition, the C-V curve measured at 200 degrees C remained essentially similar compared with the room-temperature C-V curves. These results indicate that the present process realizes a stable Al2O3/GaN interface with low interface state densities.

学術雑誌論文

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This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in Applied physics letters 109 (16) 162104, and may be found at http://aip.scitation.org/doi/abs/10.1063/1.4965296.

0003-6951

AA00543431