کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1791534 | 1524472 | 2012 | 4 صفحه PDF | دانلود رایگان |
We report the selective-area growth (SAG) of Ga-polar thin GaN nanowires on patterned GaN/sapphire (0001) substrates using metalorganic chemical vapor deposition (MOCVD) with a continuous gas supply. It has been found that the anisotropy in the growth rates of the (0001) and the {1–100} facets of GaN reaches a maximum at low precursor flow rates for both Ga source and NH3. It has also been revealed that the SAG efficiency which is dependent on pattern fill-factor should be properly taken into account in order to grow thin GaN nanowires. Based on these findings, we demonstrate the growth of GaN nanowires with a diameter of 50 nm, which is the smallest reported so far by selective-area MOCVD. Optical properties of a single GaN nanowire have been investigated by low temperature micro-photoluminescence. It has been shown that an appropriate shell layer is effective to considerably improve the properties, suggesting the importance of controlling surface states.
► Selective-area growth of GaN nanowires was demonstrated by continuous-flow MOCVD.
► The anisotropy in the growth rates reaches a maximum at low precursor flow rates.
► The selective area growth efficiency is dependent on pattern fill-factor.
► Surface states can be reduced by introducing an appropriate shell layer.
Journal: Journal of Crystal Growth - Volume 357, 15 October 2012, Pages 58–61