Photoluminescent Enhancement by Effect of Incorporation Nickel in ZnO Films Grown

Microstructured films of undoped zinc oxide (ZnO) and ZnO doped with nickel (ZnO:Ni) were grown by hot filament chemical vapor deposition (HFCVD) technique on Si (100) substrates at 500 °C. Pellets of ZnO and ZnO:NiO as oxidant agenst were used. A shift to the right around 0.17 degree of the X-Ray Diffraction pattern of the ZnO:Ni film was observed with respect to undoped ZnO films. Morphologically by Scanning Electron Microscopy was noticed a Core-Shell type growth in ZnO undoped and a nanostructured type (Nano-wire) in ZnO doped with Ni. Photoluminescence measurements showed an increase in the intensity of the green emission band of ZnO:Ni. It was attributed to defects of oxygen vacancies (VO), zinc vacancies (VZn), zinc interstitials (Zni), oxygen interstitials (Oi), and oxygen vacancies complex (VO complex) in the structure of the film. The incorporation of Ni atoms in the ZnO structure stresses the crystal lattice, leaving behind a large number of surface defects that increase the emission of PL.

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The Role of Oxygen Ambience on the Optical Characteristics of ZnO Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.711.26 ◽

2013 ◽

Vol 711 ◽

pp. 26-31

Author(s):

Feng Li ◽

Ru Yuan Ma

Keyword(s):

Grain Size ◽

Oxygen Vacancies ◽

Green Emission ◽

Intensity Change ◽

Zno Films ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

X Ray ◽

Uv Emission

Zinc oxide (ZnO) films are grown by two methods-pulse laser deposition (PLD) and radio-frequency magnetron sputtering at various oxygen ambiences. Based on x-ray diffraction spectra and photoluminescence (PL) spectra, effects of the oxygen ambient on the grain size and emission properties of the ZnO films are investigated. For the samples grown by PLD, the PL spectrum consists of a single ultraviolet (UV) peak except one sample deposited at a low O2 pressure of 7 Pa. All the samples grown by sputtering have both a UV peak and a green emission. The disappearance of the green emission of the PLD samples is ascribed to deficiency of oxygen vacancies (Ov), and the green emission of the sample grown by sputtering is due to abundant Ov. The intensity change of the UV emission is due to the variation of exciton emission, which is related to grain size and stoichiometry. The position shifting of the UV peak of the PLD samples originates from the Zn interstitial-related degradation of stoichiometry.

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Zinc Oxide Nano Walls Synthesized by Chemical Vapor Deposition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.608.127 ◽

2014 ◽

Vol 608 ◽

pp. 127-131 ◽

Cited By ~ 4

Author(s):

Suttinart Noothongkaew ◽

Supakorn Pukird ◽

Worasak Sukkabot ◽

Ki Seok An

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Room Temperature ◽

Chemical Vapor ◽

Green Emission ◽

X Ray Diffraction ◽

Ultraviolet Emission ◽

Axis Orientation ◽

X Ray ◽

Zno Nanostructure

ZnO nanowalls were synthesized by chemical vapor deposition at temperature of 650 °C for 1 hour on the silicon substrate. The morphologies of samples were characterized by scanning electron microscopy (SEM). The result from X-ray diffraction (XRD) confirmed that the ZnO nanowalls were vertical c-axis orientation. A room temperature Photoluminescence peak at 378 nm is ultraviolet emission (UV) and the broad peak at wavelengths around 450-650 nm is corresponding to the green emission of ZnO nanostructure. This synthesis may be applicable for gas sensor or solar cells.

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Synthesis of Crystalline C3N4 films and the new C-N Phases

MRS Proceedings ◽

10.1557/proc-441-717 ◽

1996 ◽

Vol 441 ◽

Author(s):

Yan Chen ◽

D. J. Johnson ◽

R. H. Prince ◽

Liping Guo ◽

E. G. Wang

Keyword(s):

Electron Microscopy ◽

Vapor Deposition ◽

Growth Parameters ◽

Chemical Vapor ◽

Monoclinic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Lattice Constants ◽

Transmission Electron ◽

Hot Filament

AbstractCrystalline C-N films composed of α- and β-C3N4, as well as other C-N phases, have been synthesized via bias-assisted hot-filament chemical vapor deposition using a gas mixture of nitrogen and methane. Scanning electron microscopy(SEM), energy dispersive X-ray (EDX) analysis, X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the films. Lattice constants of the α- and β-C3N4 phases obtained coincide very well with the theoretical values. In addition to these phases, two new C-N phases in the films have been identified by TEM and XRD; one having a tetragonal structure with a = 5.65 Å, c = 2.75Å, and the second having a monoclinic structure with a = 5.065 Å, b= 11.5 Å, c = 2.801 Å and β = 96°. Their stoichiometric values and atomic arrangements have not yet been identified. Furthermore, variation in growth parameters, for example methane concentration, bias voltage, etc., can yield preferred growth of different C-N phases.

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Investigation of Oxygen Vacancies in Micro-Patterned PZT Thin Films Using Raman Spectroscopy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.421-422.135 ◽

2009 ◽

Vol 421-422 ◽

pp. 135-138

Author(s):

Ken Nishida ◽

Minoru Osada ◽

Shintaro Yokoyama ◽

Takafumi Kamo ◽

Takashi Fujisawa ◽

...

Keyword(s):

Raman Spectroscopy ◽

Oxygen Vacancies ◽

Chemical Vapor ◽

Organic Chemical ◽

X Ray Diffraction ◽

Si Substrate ◽

X Ray ◽

Vapor Phase Deposition ◽

Pzt Films ◽

Metal Organic

Micro-patterned Pb(Zr,Ti)O3 (PZT) films with dot-pattern were grown by metal organic chemical vapor phase deposition (MOCVD). Micro-patterned Pb(Zr,Ti)O3 (PZT) films were formed on dot-patterned SrRuO3 (SRO) buffer layer that was prepared by MOCVD through the metal mask on (111)Pt/Ti/SiO2/Si substrate. The orientation of dot-patterned PZT films was ascertained by the micro-beam x-ray diffraction (XRD) and their crystallinity was characterized by Raman spectroscopy. It was found that PZT films were oriented to (111) on dot-pattern, while (100)/(001) out of dot-pattern and the amount of oxygen vacancies at the circumference of the dot-pattern were larger than that of center of dot-pattern.

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Application of a Thermobalance for studying Deposition kinetics of Diamond Films

MRS Proceedings ◽

10.1557/proc-162-157 ◽

1989 ◽

Vol 162 ◽

Author(s):

Jerry Czarnecki ◽

David Thumim

Keyword(s):

Diamond Films ◽

Chemical Vapor ◽

Carbon Films ◽

X Ray Diffraction ◽

X Ray ◽

Deposition Kinetics ◽

Oxidation Rates ◽

Exponential Increase ◽

Hot Filament ◽

Kinetics Of

ABSTRACTWeight recording using a thermobalance type Cahn TG-171 has been applied to study Hot, Filament Enhanced Chemical Vapor Deposition (HFCVD) of carbon films from methane. Changes in the deposition rates during each individual process may indicate four stages of the deposition kinetics: 1- generation of nuclei (slow, linear); 2- growth on nuclei (exponential increase); 3- aggregation of crystals (slowing); 4- growth on the surface of diamond film, completely covering the substrate (linear). An attempt to determine the concentration of graphite in the deposited layer, based on differences in oxidation rates of diamond and graphite has been proposed, as supplementary to X-ray diffraction and Raman spectroscopy.

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Fabrication and Applications of Ultra-Smooth Composite Diamond Coated WC-Co Drawing Dies

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.175.233 ◽

2011 ◽

Vol 175 ◽

pp. 233-238 ◽

Cited By ~ 3

Author(s):

Bin Shen ◽

Fang Hong Sun ◽

Zhi Ming Zhang ◽

He Sheng Shen ◽

Song Shou Guo

Keyword(s):

Chemical Vapor ◽

X Ray Diffraction ◽

Entry Zone ◽

X Ray ◽

Nano Crystalline ◽

Composite Diamond ◽

And Performance ◽

Hot Filament ◽

Drawing Dies

Micro/nano-crystalline multilayered ultra-smooth diamond (USCD) films are deposited on the interior-hole surface of conventional WC-Co drawing dies with a combined process consisting of the hot filament chemical vapor deposition (HFCVD) method and polishing technique. Scanning electron microscopy (SEM), surface profilemeter, Raman spectroscopy and X-ray diffraction (XRD) are employed to provide a characterization of as-deposited USCD films. The results exhibit that as-deposited USCD films present an ultra-smooth surface, its surface roughness values (Ra) in the entry zone, drawing zone and bearing zone are measured as 25.7 nm, 23.3 nm and 25.5 nm respectively. Furthermore, the working lifetime and performance of as-fabricated USCD coated drawing dies are examined in producing copper tubes with hollow sinking, fixed plug and floating plug. The results show that the lifetime of USCD coated drawing is as more than 30 times as that of WC-Co drawing dies in the drawing process with hollow sinking, 7 times in the fixed plug drawing and 10 times in the floating drawing.

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Characterization of Nitrogen Doped Diamond Electrodes Produced by Hot Filament Chemical Vapor Deposition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.802.180 ◽

2014 ◽

Vol 802 ◽

pp. 180-185 ◽

Cited By ~ 1

Author(s):

Nazir M. Santos ◽

Tatiane M. Arantes ◽

Neidênei G. Ferreira ◽

Mauricio R. Baldan

Keyword(s):

Raman Spectroscopy ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Nitrogen Doping ◽

Chemical Vapor ◽

X Ray Diffraction ◽

Diamond Electrodes ◽

X Ray ◽

Nitrogen Doped ◽

Hot Filament

The purpose of this work is to study the structural and morphological modification of the surface of the n-type diamond electrodes as a function of nitrogen doping. The characterizations of these electrodes were made using Raman Spectroscopy, Contact Angle, X-ray diffraction and Scanning Electron Microscopy (SEM). The nitrogen-doped diamond (NDD) electrodes were produced using Hot Filament-assisted Chemical Vapor Deposition method (HFCVD) from methane, hydrogen and nitrogen in the gas mixture. The results from Raman spectroscopy show that the diamond films obtained with nitrogen addition presented one large band at 1100-1700 cm-1. The SEM images showed that the variation in the nitrogen doping influenced the growth rate of films by promoting changes in the sizes of grains from microcrystalline to nanocrystalline texture. This behavior supported the results obtained from X-ray diffraction analyses. It was possible to verify a decrease in the crystallite size as a function of the nitrogen increase.

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Growth of Highly Oriented ZnO Nanorods by Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-703-v2.4 ◽

2001 ◽

Vol 703 ◽

Cited By ~ 2

Author(s):

Sai-Chang Liu ◽

Jih-Jen Wu

Keyword(s):

Zno Nanorods ◽

Chemical Vapor ◽

Green Emission ◽

Fused Silica ◽

Near Band Edge ◽

Band Edge Emission ◽

X Ray Diffraction ◽

Green Emission Band ◽

Vaporization Temperature ◽

Zno Crystal

ABSTRACTHighly-oriented ZnO nanorods were grown on the fused silica substrates by a thermal CVD technique using Zinc acetylacetonate (Zn(C5H7O2)2). The substrate was heated to 500°C and the vaporization temperature of Zn(C5H7O2)2 was keep at around 135°C. X-ray diffraction and TEM analyses reveal that the nanorods are preferentially oriented toward the c-axis direction. Photoluminescence (PL) and absorption measurements show a strong emission at around 380nm which corresponds to the near band-edge emission of the bulk ZnO. Moreover, the negligible green emission band in PL spectrum and the absence of E1(LO) mode of the ZnO crystal in Raman spectrum indicate a low concentration of oxygen vacancy in the highly-oriented ZnO nanorods.

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Preparation and Photoluminescence Properties of ZnO-Covered Carbon Fibers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.510 ◽

2012 ◽

Vol 463-464 ◽

pp. 510-514

Author(s):

Jun Zeng

Keyword(s):

Carbon Fibers ◽

Oxygen Vacancies ◽

Green Emission ◽

Photoluminescence Properties ◽

X Ray Diffraction ◽

Red Emission ◽

Interstitial Carbon ◽

X Ray ◽

Zno Nanosheets ◽

Pl Spectrum

This paper reports that ZnO nanosheet-covered carbon fibers are synthesized by thermal oxidation of zinc films deposited on carbon fiber surfaces. The structure and optical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectrum. The result shows that all of the cabon fibers are coated ZnO nanosheets. An orange-red emission around 683 nm was found in PL spectrum when the sample prepared at 400 oC for 4 hours in air. I considered that the growth of ZnO nanosheets may be related to the size of substrates and reaction temperature. The orange-red emission was resulted from the interstitial carbon of ZnO-nanosheet-covered fibers, and green emission results from the oxygen vacancies.

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SYNTHESIS OF HIGH QUALITY CRYSTALLINE C-N FILMS ON SILICON

Modern Physics Letters B ◽

10.1142/s0217984996000626 ◽

1996 ◽

Vol 10 (12) ◽

pp. 567-571 ◽

Cited By ~ 17

Author(s):

YAN CHEN ◽

E.G. WANG ◽

FENG CHEN ◽

LIPING GUO

Keyword(s):

Electron Microscopy ◽

Vapor Deposition ◽

Interfacial Layer ◽

Chemical Vapor ◽

X Ray Diffraction ◽

High Quality ◽

X Ray ◽

Transmission Electron ◽

Hot Filament ◽

Microscopy Images

High quality crystalline C–N films have been synthesized via hot filament chemical vapor deposition using a gas mixture of nitrogen and methane. Scanning electron microscopy images show that a high density of crystalline clusters has been achieved. The clusters are composed of small columnar crystals (20–200 nm across) with hexagonal facets. Energy dispersive X ray analysis indicates a relative nitrogen:carbon composition of 1.30–2.5. X ray diffraction results indicate the films composed of β- and α- C 3 N 4 phases. Together with transmission electron microscopy analyses, we suggest that an interfacial layer C 3−x Si x N 4 is formed between the silicon substrate and the crystalline carbonnitride films.

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