Influence of ZnO seed crystals and annealing on the optical quality of low-temperature grown ZnO nanorods

The effects of Au on the growth of ZnO nanostructures on Si by metal organic chemical vapor deposition (MOCVD) at a relatively low temperature (450°C) were investigated. The experimental results showed that Au nanoparticles played a critical role during the growth of the ZnO nanostructures and affected their morphology and optical properties. It was found that Au nanoparticles particularly affected the nucleation of ZnO nanostructures during the growth process and the Au -assisted growth mechanism of ZnO nanostructures should be ascribed to the vapor–solid (VS) mechanism. The formation of a nanoneedle may be attributed to a more reactive interface between Au and ZnO , which leads to more zinc gaseous species absorbed near the interface. Different nucleation sites on ZnO nuclei resulted in the disorder of ZnO nanoneedles. Moreover, the crystalline quality of nano- ZnO was improved due to the presence of Au , according to the smaller full width at half maximum (FWHM) of the low-temperature exciton emission. We confirmed that ZnO nanoneedles showed better crystalline quality than ZnO nanorods through the HRTEM images and the SAED patterns. The reason for the improvement of the crystalline quality of nano- ZnO may be due to the less lattice mismatch.

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Optical Properties of Doped Cd1−xMnxTe

MRS Proceedings ◽

10.1557/proc-89-281 ◽

1986 ◽

Vol 89 ◽

Author(s):

Y. Lansari ◽

N. C. Giles ◽

J. F. Schetzina ◽

P. Becia ◽

D. Kaiser

Keyword(s):

Optical Properties ◽

Low Temperature ◽

Spectral Range ◽

Room Temperature ◽

Far Infrared ◽

Optical Quality ◽

Structural Quality ◽

Reflectance Measurements ◽

Low Temperature Photoluminescence

AbstractThe introduction of phosphorus and arsenic dopants into bulk Cd1−xMnx Te crystals grown by the Bridgman-Stockbarger technique has been studieA-with respect to the resulting optical properties. Samples with a Mn composition in the range 0.10 < x < 0.30, both as-grown and annealed, were investigated. A combination of room temperature transmittance and reflectance measurements over the spectral range from the ultraviolet to the far infrared has been used to gain information concerning the structural quality of the samples. Low temperature photoluminescence measurements (1.6−5 K) were used to determine optical quality and excitonic energies.

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Growth of compact arrays of optical quality single crystalline ZnO nanorods by low temperature method

Bulletin of Materials Science ◽

10.1007/s12034-008-0046-9 ◽

2008 ◽

Vol 31 (3) ◽

pp. 283-289 ◽

Cited By ~ 17

Author(s):

Manoranjan Ghosh ◽

Ritwik Bhattacharyya ◽

A. K. Raychaudhuri

Keyword(s):

Low Temperature ◽

Zno Nanorods ◽

Optical Quality ◽

Single Crystalline ◽

Temperature Method

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A STUDY ON THE INDIUM-INDUCED VARIATIONS IN PHOTOLUMINESCENCE PROPERTIES OF INDIUM-DOPED ZINCOXIDE NANORODS

International Journal of Nanoscience ◽

10.1142/s0219581x09005785 ◽

2009 ◽

Vol 08 (01n02) ◽

pp. 137-145 ◽

Cited By ~ 1

Author(s):

M. N. JUNG ◽

J. E. KOO ◽

J. H. CHANG ◽

T.-I. JEON ◽

W. J. LEE ◽

...

Keyword(s):

Zno Nanorods ◽

Peak Position ◽

Excitation Power ◽

Optical Quality ◽

Structural Quality ◽

In Doping ◽

Induced Changes ◽

Relationship Of ◽

Good Optical Quality

In doped ZnO nanorods ( ZnO : In NRs) were grown on Si (111) substrates by using AuGe as a catalyst. In-concentration was controlled as high as 0.33 at.%. The length L to diameter D relationship of NRs revealed that the growth mechanism should be explained in terms of not a simple vapor–liquid–solid (VLS) mechanism but a diffusion-induced growth model. In-induced changes have been investigated from the viewpoint of photoluminescence (PL) property. At room temperature, an increase of extrinsic carrier concentration and interaction with excitons were estimated from the blueshift of peak position and decrease of luminescence intensity. Also, narrow linewidth of low-temperature PL spectra characterized the high structural quality of ZnO : In NRs. We have assigned several PL lines and confirmed the assignment by using excitation power and temperature dependence PL. Considerable evidence of crystal quality degradation was not observed from both measurements; however, we could observe that a defect and donor-bound-exciton complex dominate the PL spectrum. ZnO : In NRs shows good optical quality within our experimental range, and this result strongly supports the feasibility of In -doping to enhance the electrical property of ZnO -based nanostructure.

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Exciton Localization and Stimulated Emission of ZnO Nanorods

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.538.161 ◽

2013 ◽

Vol 538 ◽

pp. 161-164 ◽

Cited By ~ 2

Author(s):

Chun Ping Li ◽

Li Zhang ◽

Chang Jie Liu ◽

Ge Gao

Keyword(s):

Zno Nanorods ◽

Optical Quality ◽

Stimulated Emission ◽

High Yield ◽

X Ray Diffraction ◽

Localization Property ◽

Exciton Localization ◽

Transmission Electron ◽

Intensity Changes

High yield ZnO nanorods are synthesized by a simple wet chemical method. The crystal morphology and structure of the ZnO nanorods are examined by transmission electron microscopy (TEM) and X-Ray Diffraction (XRD), respectively. The properties of the excitonic luminescence are investigated by temperature dependent photoluminescence (PL) spectra. Barely observed visible emission band indicates the good optical quality of the ZnO nanorods and the abnormal position and intensity changes of the emission peaks indicates the localization property of exciton.

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Fabrication and Optical Properties of Monodisperse Fine Zinc Oxide Nanorods

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.409 ◽

2010 ◽

Vol 663-665 ◽

pp. 409-412

Author(s):

Chun Ping Li ◽

Jian Zhang ◽

Hua Min Yu ◽

Xiu Juan Guo

Keyword(s):

Optical Properties ◽

Quantum Confinement ◽

Zno Nanorods ◽

Optical Quality ◽

Zinc Oxide Nanorods ◽

Photoluminescence Spectra ◽

Aspect Ratios ◽

Quantum Confinement Effects ◽

Oxide Nanorods

Highly monodisperse ZnO nanorods were synthesized by simple solution chemical process. The produced ZnO nanorods have uniform diameters about 30 nm with average aspect ratios more than 40. Raman and photoluminescence measurements were used to examine their optical properties. Raman spectrum presents weak quantum confinement effects of the fine nanorods. Laser power-dependent photoluminescence spectra show the products have intense UV emissions with narrow full width at the half maximum (FWHM). All the performed experiments determine the good crystal and optical quality of synthesized nanorods.

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