Ultrashort carrier lifetime of vapor–liquid–solid-grown GaN/InGaN multi-quantum-well coaxial nanorods

Abstract Luminescence and carrier dynamics of GaN/InGaN multi-quantum-well coaxial nanorods (MCNRs) were studied by means of photoluminescence (PL), cathodoluminescence (CL) and time-resolved PL (TRPL). The PL of as-grown MCNRs showed an intense blue emission together with broad emission at longer wavelengths. CL measurements of several single MCNRs attributed the broad emission to the wetting layer frequently observed in vapor–liquid–solid-grown nanorods. Non-single exponential intensity decays were observed by TRPL, which were ascribed to the In fluctuation in the InGaN alloy. Radiative and non-radiative lifetimes were then calculated via a stretched exponential model. An ultrafast carrier lifetime in the range of a few tens of picoseconds along with a high internal quantum efficiency (IQE) of about 59% resulted. The ultrafast carrier lifetimes were attributed to the improvement in the carrier collection efficiency due to the radial heterostructuring of GaN with InGaN shells, while the high IQE implied that carriers were mostly recombined radiatively. This study reveals that the coaxial growth of InGaN with GaN nanorods resulted in an ultrafast carrier lifetime and a luminescence efficiency that could be controlled by adjusting the growth temperature gap between the GaN and the InGaN.

[1]  J. Lee,et al.  Controlled growth mode of high-aspect-ratio GaN nanorods by Ni/In/Ga catalyst , 2013 .

[2]  I. Krestnikov,et al.  Quantum dot origin of luminescence in InGaN-GaN structures , 2002 .

[3]  Hao-Chung Kuo,et al.  Size-Dependent Strain Relaxation and Optical Characteristics of InGaN/GaN Nanorod LEDs , 2009, IEEE Journal of Selected Topics in Quantum Electronics.

[4]  S. Denbaars,et al.  Characterization of high-quality InGaN/GaN multiquantum wells with time-resolved photoluminescence , 1998 .

[5]  S. Nutt,et al.  InGaN/GaN multiple quantum wells grown on nonpolar facets of vertical GaN nanorod arrays. , 2012, Nano letters.

[6]  Yong Ding,et al.  Multi-quantum-well nanowire heterostructures for wavelength-controlled lasers. , 2008, Nature materials.

[7]  T. Onuma,et al.  Improved Emission Efficiency in InGaN / GaN Quantum Wells with Compositionally-Graded Barriers Studied by Time-Resolved Photoluminescence Spectroscopy , 2003 .

[8]  C. Bougerol,et al.  Structural and optical properties of InGaN/GaN nanowire heterostructures grown by PA-MBE , 2011, Nanotechnology.

[9]  A. Alec Talin,et al.  Transport imaging for contact-free measurements of minority carrier diffusion in GaN, GaN/AlGaN, and GaN/InGaN core-shell nanowires , 2011 .

[10]  J. Chyi,et al.  Tailoring of the Wave Function Overlaps and the Carrier Lifetimes in InAs/GaAs1−xSbx Type-II Quantum Dots , 2010 .

[11]  P. Bhattacharya,et al.  Spin relaxation in InGaN quantum disks in GaN nanowires. , 2011, Nano letters.

[12]  Kenji Hiruma,et al.  Fabrication of Axial and Radial Heterostructures for Semiconductor Nanowires by Using Selective-Area Metal-Organic Vapor-Phase Epitaxy , 2012 .

[13]  S. Höfling,et al.  Structural and optical properties of InGaN-GaN nanowire heterostructures grown by molecular beam epitaxy , 2011 .

[14]  Pallab Bhattacharya,et al.  InGaN/GaN disk-in-nanowire white light emitting diodes on (001) silicon , 2011 .

[15]  F. H. Long,et al.  Time-resolved photoluminescence measurements of InGaN light-emitting diodes , 1998 .

[16]  Hao-Chung Kuo,et al.  Fabrication and luminescent properties of core-shell InGaN/GaN multiple quantum wells on GaN nanopillars , 2012 .

[17]  J. Kwak,et al.  Effects of reduced exciton diffusion in InGaN/GaN multiple quantum well nanorods. , 2012, Optics express.

[18]  Fang Qian,et al.  Nanowire electronic and optoelectronic devices , 2006 .

[19]  P. Bhattacharya,et al.  Excitation dependent two-component spontaneous emission and ultrafast amplified spontaneous emission in dislocation-free InGaN nanowires , 2013 .

[20]  M. S. Skolnick,et al.  Influence of GaN barrier growth temperature on the photoluminescence of InGaN/GaN heterostructures , 2002 .

[21]  V. Purushothaman,et al.  Interplay of VLS and VS growth mechanism for GaN nanowires by a self-catalytic approach , 2012 .

[22]  Martin Strassburg,et al.  Molecular beam epitaxial growth and optical properties of red-emitting (λ = 650 nm) InGaN/GaN disks-in-nanowires on silicon , 2013 .

[23]  J. Eymery,et al.  M-plane core-shell InGaN/GaN multiple-quantum-wells on GaN wires for electroluminescent devices. , 2011, Nano letters.

[24]  S. Aloni,et al.  Growth of GaN@InGaN Core-Shell and Au-GaN Hybrid Nanostructures for Energy Applications , 2009 .

[25]  P. Yang,et al.  Metalorganic Chemical Vapor Deposition Route to GaN Nanowires with Triangular Cross Sections , 2003 .

[26]  George T. Wang,et al.  Improvement in aligned GaN nanowire growth using submonolayer Ni catalyst films , 2008 .

[27]  Charles M. Lieber,et al.  Gallium Nitride-Based Nanowire Radial Heterostructures for Nanophotonics , 2004 .

[28]  K. Hiramatsu.  Epitaxial lateral overgrowth techniques used in group III nitride epitaxy , 2001 .

[29]  P. Lefebvre,et al.  Selective area growth and characterization of InGaN nano-disks implemented in GaN nanocolumns with different top morphologies , 2012 .

[30]  I. Krestnikov,et al.  Time‐Resolved Studies of InGaN/GaN Quantum Dots , 2002 .

[31]  S. Nakamura,et al.  Strain-induced polarization in wurtzite III-nitride semipolar layers , 2006 .

[32]  C. Bougerol,et al.  Growth mechanism and properties of InGaN insertions in GaN nanowires , 2012, Nanotechnology.

[33]  Laurent Boudou,et al.  Physico-chemical observations on polyethylene base resin under the effect of thermal ageing , 2002 .

[34]  G. Shen,et al.  One-dimensional nanostructures for electronic and optoelectronic devices , 2010, Frontiers of Optoelectronics in China.

[35]  S. Gwo,et al.  InGaN/GaN nanorod array white light-emitting diode , 2010 .

[36]  A. A. Talin,et al.  GaN nanowire surface state observed using deep level optical spectroscopy , 2010 .

[37]  George T. Wang,et al.  Highly aligned, template-free growth and characterization of vertical GaN nanowires on sapphire by metal–organic chemical vapour deposition , 2006 .

[38]  R. Leonelli,et al.  Recombination dynamics in InGaN/GaN nanowire heterostructures on Si(111) , 2013, Nanotechnology.

[39]  Christopher C. S. Chan,et al.  Optical studies of the surface effects from the luminescence of single GaN/InGaN nanorod light emitting diodes fabricated on a wafer scale , 2013 .

[40]  Jeremy B. Wright,et al.  The influence of radial heterostructuring on carrier dynamics in gallium nitride nanowires , 2012 .