Alignment control and atomically-scaled heteroepitaxial interface study of GaN nanowires

IMR OpenIR

	Alignment control and atomically-scaled heteroepitaxial interface study of GaN nanowires
	Liu, Qingyun; Liu, Baodan; Yang, Wenjin; Yang, Bing; Zhang, Xinglai; Labbe, Christophe; Portier, Xavier; An, Vladimir; Jiang, Xin; Liu, BD; Jiang, X (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci SYNL, 72 Wenhua Rd, Shenyang 110016, Peoples R China.
	2017-04-28
发表期刊	NANOSCALE
ISSN	2040-3364
卷号	9 期号:16 页码:5212-5221
摘要	Well-aligned GaN nanowires are promising candidates for building high-performance optoelectronic nanodevices. In this work, we demonstrate the epitaxial growth of well-aligned GaN nanowires on a [0001]-oriented sapphire substrate in a simple catalyst-assisted chemical vapor deposition process and their alignment control. It is found that the ammonia flux plays a key role in dominating the initial nucleation of GaN nanocrystals and their orientation. Typically, significant improvement of the GaN nanowire alignment can be realized at a low NH3 flow rate. X-ray diffraction and cross-sectional scanning electron microscopy studies further verified the preferential orientation of GaN nanowires along the [0001] direction. The growth mechanism of GaN nanowire arrays is also well studied based on cross-sectional highresolution transmission electron microscopy (HRTEM) characterization and it is observed that GaN nanowires have good epitaxial growth on the sapphire substrate following the crystallographic relationship between (0001)(GaN)parallel to(0001)(sapphire) and (101 (1) over bar0)(GaN)parallel to(11 (2) over bar0)(sapphire). Most importantly, periodic misfit dislocations are also experimentally observed in the interface region due to the large lattice mismatch between the GaN nanowire and the sapphire substrate, and the formation of such dislocations will favor the release of structural strain in GaN nanowires. HRTEM analysis also finds the existence of "type I" stacking faults and voids inside the GaN nanowires. Optical investigation suggests that the GaN nanowire arrays have strong emission in the UV range, suggesting their crystalline nature and chemical purity. The achievement of aligned GaN nanowires will further promote the wide applications of GaN nanostructures toward diverse high-performance optoelectronic nanodevices including nano-LEDs, photovoltaic cells, photodetectors etc.; Well-aligned GaN nanowires are promising candidates for building high-performance optoelectronic nanodevices. In this work, we demonstrate the epitaxial growth of well-aligned GaN nanowires on a [0001]-oriented sapphire substrate in a simple catalyst-assisted chemical vapor deposition process and their alignment control. It is found that the ammonia flux plays a key role in dominating the initial nucleation of GaN nanocrystals and their orientation. Typically, significant improvement of the GaN nanowire alignment can be realized at a low NH3 flow rate. X-ray diffraction and cross-sectional scanning electron microscopy studies further verified the preferential orientation of GaN nanowires along the [0001] direction. The growth mechanism of GaN nanowire arrays is also well studied based on cross-sectional highresolution transmission electron microscopy (HRTEM) characterization and it is observed that GaN nanowires have good epitaxial growth on the sapphire substrate following the crystallographic relationship between (0001)(GaN)parallel to(0001)(sapphire) and (101 (1) over bar0)(GaN)parallel to(11 (2) over bar0)(sapphire). Most importantly, periodic misfit dislocations are also experimentally observed in the interface region due to the large lattice mismatch between the GaN nanowire and the sapphire substrate, and the formation of such dislocations will favor the release of structural strain in GaN nanowires. HRTEM analysis also finds the existence of "type I" stacking faults and voids inside the GaN nanowires. Optical investigation suggests that the GaN nanowire arrays have strong emission in the UV range, suggesting their crystalline nature and chemical purity. The achievement of aligned GaN nanowires will further promote the wide applications of GaN nanostructures toward diverse high-performance optoelectronic nanodevices including nano-LEDs, photovoltaic cells, photodetectors etc.
部门归属	[liu, qingyun ; liu, baodan ; yang, wenjin ; yang, bing ; zhang, xinglai ; jiang, xin] chinese acad sci, inst met res, shenyang natl lab mat sci synl, 72 wenhua rd, shenyang 110016, peoples r china ; [liu, qingyun] univ chinese acad sci, 19 a yuquan rd, beijing 100049, peoples r china ; [labbe, christophe ; portier, xavier] normandie univ, cimap cnrs, cea, ensicaen, 6 bd marechal juin, f-14050 caen 4, france ; [an, vladimir] natl res tomsk polytech univ, inst high technol phys, 30 lenin ave, tomsk 634050, russia
学科领域	Chemistry, Multidisciplinary ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary ; Physics, Applied
资助者	Knowledge Innovation Program of Institute of Metal Research, Chinese Academy of Sciences [Y2NCA111A1, Y3NCA111A1]; Youth Innovation Promotion Association, Chinese Academy of Sciences [Y4NC711171]; French ANR (Agence Nationale de la Recherche) institution
收录类别	SCI
语种	英语
WOS记录号	WOS:000399809400021
引用统计	被引频次：23[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/78175
专题	中国科学院金属研究所
通讯作者	Liu, BD; Jiang, X (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci SYNL, 72 Wenhua Rd, Shenyang 110016, Peoples R China.
推荐引用方式 GB/T 7714	Liu, Qingyun,Liu, Baodan,Yang, Wenjin,et al. Alignment control and atomically-scaled heteroepitaxial interface study of GaN nanowires[J]. NANOSCALE,2017,9(16):5212-5221.
APA	Liu, Qingyun.,Liu, Baodan.,Yang, Wenjin.,Yang, Bing.,Zhang, Xinglai.,...&Jiang, X .(2017).Alignment control and atomically-scaled heteroepitaxial interface study of GaN nanowires.NANOSCALE,9(16),5212-5221.
MLA	Liu, Qingyun,et al."Alignment control and atomically-scaled heteroepitaxial interface study of GaN nanowires".NANOSCALE 9.16(2017):5212-5221.