Homoepitaxial growth of catalyst-free GaN wires on N-polar substrates

Chen, Xiao Jun; Perillat-Merceroz, Guillaume; Sam-Giao, Diane; Durand, Christophe; Eymery, J.

doi:10.1063/1.3497078

Cited by 121 publications

(134 citation statements)

References 18 publications

(16 reference statements)

Supporting

Mentioning

129

Contrasting

Order By: Relevance

“…41 The polarity of GaN nanorods was found to be critical for the morphology of the nanostructures by several groups. 42,44,84,85 Chen et al employed convergent beam electron diffraction to investigate the polarity of GaN rods selectively grown by MOVPE using SiNx as mask material. 84 They show the coexistence of N-and Ga-polarities in GaN nanorods: the central part is N-polar while inclined facets are Ga-polar.…”

Section: B Mocvd Growthmentioning

confidence: 99%

“…42,44,84,85 Chen et al employed convergent beam electron diffraction to investigate the polarity of GaN rods selectively grown by MOVPE using SiNx as mask material. 84 They show the coexistence of N-and Ga-polarities in GaN nanorods: the central part is N-polar while inclined facets are Ga-polar. Ga-polar crystals are preferentially formed on the SiN x mask (overgrowth), while N-polar crystals are preferentially present on the AlN/c-sapphire surface.…”

Section: B Mocvd Growthmentioning

confidence: 99%

See 1 more Smart Citation

GaN based nanorods for solid state lighting

Li¹,

Waag

2012

Journal of Applied Physics

487

394

View full text Add to dashboard Cite

In recent years, GaN nanorods are emerging as a very promising novel route toward devices for nano-optoelectronics and nano-photonics. In particular, core-shell light emitting devices are thought to be a breakthrough development in solid state lighting, nanorod based LEDs have many potential advantages as compared to their 2 D thin film counterparts. In this paper, we review the recent developments of GaN nanorod growth, characterization, and related device applications based on GaN nanorods. The initial work on GaN nanorod growth focused on catalyst-assisted and catalyst-free statistical growth. The growth condition and growth mechanisms were extensively investigated and discussed. Doping of GaN nanorods, especially p-doping, was found to significantly influence the morphology of GaN nanorods. The large surface of 3 D GaN nanorods induces new optical and electrical properties, which normally can be neglected in layered structures. Recently, more controlled selective area growth of GaN nanorods was realized using patterned substrates both by metalorganic chemical vapor deposition (MOCVD) and by molecular beam epitaxy (MBE). Advanced structures, for example, photonic crystals and DBRs are meanwhile integrated in GaN nanorod structures. Based on the work of growth and characterization of GaN nanorods, GaN nanoLEDs were reported by several groups with different growth and processing methods. Core/shell nanoLED structures were also demonstrated, which could be potentially useful for future high efficient LED structures. In this paper, we will discuss recent developments in GaN nanorod technology, focusing on the potential advantages, but also discussing problems and open questions, which may impose obstacles during the future development of a GaN nanorod based LED technology.

show abstract

Section: B Mocvd Growthmentioning

confidence: 99%

Section: B Mocvd Growthmentioning

confidence: 99%

GaN based nanorods for solid state lighting

Li¹,

Waag

2012

Journal of Applied Physics

487

394

View full text Add to dashboard Cite

show abstract

“…Core−shell GaN wire p−n junctions were grown using catalyst-free MOVPE 33,34 on a N-polar GaN freestanding substrate (sample #1) or a n-type (100) silicon substrate (sample #2). As shown in Figure 1a, a selective area growth through a mask was employed to grow wurtzite n-doped GaN wires with a radius chosen in the range of 500−1200 nm (defined as hexagon side length) and a length chosen in the range of 5−10 μm.…”

mentioning

confidence: 99%

Direct Imaging of p–n Junction in Core–Shell GaN Wires

et al. 2014

View full text Add to dashboard Cite

While core−shell wire-based devices offer a promising path toward improved optoelectronic applications, their development is hampered by the present uncertainty about essential semiconductor properties along the threedimensional (3D) buried p−n junction. Thanks to a crosssectional approach, scanning electron beam probing techniques were employed here to obtain a nanoscale spatially resolved analysis of GaN core−shell wire p−n junctions grown by catalyst-free metal−organic vapor phase epitaxy on GaN and Si substrates. Both electron beam induced current (EBIC) and secondary electron voltage constrast (VC) were demonstrated to delineate the radial and axial junction existing in the 3D structure. The Mg dopant activation process in p-GaN shell was dynamically controlled by the ebeam exposure conditions and visualized thanks to EBIC mapping. EBIC measurements were shown to yield local minority carrier/exciton diffusion lengths on the p-side (∼57 nm) and the n-side (∼15 nm) as well as depletion width in the range 40−50 nm. Under reverse bias conditions, VC imaging provided electrostatic potential maps in the vicinity of the 3D junction from which acceptor N a and donor N d doping levels were locally determined to be N a = 3 × 10 18 cm −3 and N d = 3.5 × 10 18 cm −3 in both the axial and the radial junction. Results from EBIC and VC are in good agreement. This nanoscale approach provides essential guidance to the further development of core−shell wire devices.

show abstract

“…20 The high-temperature (for example 900 o C for the case of rf-MBE) N-rich growth of GaN resulted in N-polar GaN nanocolumns with flat top surfaces (c-faces). 15 However, the low-temperature growth tended to form the small oblique crystal facets at the corners of the nanocolumn top edges; on the Ga-rich oblique epitaxial facets, outwardly oriented single dangling bonds of Ga and/or group III elements continuously appeared during the growth of InGaN at the low temperature, possibly initiating the fast lateral growth. At the same time, the tops of the Ga-polar GaN nanocolumns basically possessed a hexagonal pyramidal configuration 11 with InGaN layers grown on the side faces; the Ga-rich oblique epitaxial surfaces possess the triplet dangling bonds with less directionality and, thus, the InGaN layers only grew on the side faces.…”

Section: Experiments and Resultsmentioning

confidence: 99%

“…It is known that N-polar GaN nanocolumns can be grown on N-polar GaN substrates. 15 However, the growth mechanism of the peculiar nanostructure is not yet completely understood. The key finding in this study is that the growth of InGaN crystals on N-polarity GaN nanocolumns led to the peculiar hexagonal nanoplate structure.…”

Section: Introductionmentioning

confidence: 99%

Well-arranged novel InGaN hexagonal nanoplates at the tops of nitrogen-polarity GaN nanocolumn arrays

Kouno

Kishino

2012

AIP Advances

View full text Add to dashboard Cite

Periodically arranged novel InGaN hexagonal nanoplates were fabricated at the tops of square-lattice N-polarity GaN nanocolumn arrays. The key finding in this work is that the growth of InGaN on N-polarity GaN nanocolumns led to a peculiar nanoplate structure. The InGaN nanoplates with thicknesses of 50-100 nm extended outward from the narrow nanocolumns with diameters of 100-150 nm, to form larger hexagonal nanoplates with a typical side length of 250 nm

show abstract

Homoepitaxial growth of catalyst-free GaN wires on N-polar substrates

Cited by 121 publications

References 18 publications

GaN based nanorods for solid state lighting

GaN based nanorods for solid state lighting

Direct Imaging of p–n Junction in Core–Shell GaN Wires

Well-arranged novel InGaN hexagonal nanoplates at the tops of nitrogen-polarity GaN nanocolumn arrays

Contact Info

Product

Resources

About