Influence of local atomic configuration in AlGdN phosphor thin films on deep ultra-violet luminescence intensity

WO3:Mo and WO3:Ti thin films have been deposited on FTO/Glass substrates by the pulsed chemical spray technique at a substrate temperature of Ts= 450°C. The influence of Mo and Ti doping on the structural, electrical, and optical behavior of WO3thin films, has been studied by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), Ultra Violet and Visible Spectrometry (UV-VIS), and Surface Conductivity Methods (Four Points). Doped WO3films presents similar polycrystalline structures but with noticeable modifications in surface configurations at micrometric and nanometric levels, as the Mo and Ti concentration is systematically increased in the starting sprayed solution. From processed High-Resolution Electron Micrographs (HREM), a low density of structural defects was found on pure and doped WO3grains. This lead to conclude that variations in films surface characteristics are mainly related with metallic doping concentrations which in turn, have noticeable influence in electrical and optical behaviors reported in this work.

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Large enhancement of ultra-violet photoresponse of silicon-nanoparticle-embedded porous silicon thin films by rapid-thermal-oxidation treatment

Microelectronic Engineering ◽

10.1016/j.mee.2015.08.011 ◽

2015 ◽

Vol 148 ◽

pp. 70-73 ◽

Cited By ~ 5

Author(s):

Kuen-Hsien Wu ◽

Chong-Wei Li ◽

Jung-Hsuan Liu

Keyword(s):

Thin Films ◽

Porous Silicon ◽

Thermal Oxidation ◽

Ultra Violet ◽

Oxidation Treatment ◽

Silicon Nanoparticle ◽

Rapid Thermal Oxidation ◽

Silicon Thin Films ◽

Large Enhancement

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Atomic configuration of the interface between epitaxial Gd doped HfO2 high k thin films and Ge (001) substrates

Journal of Applied Physics ◽

10.1063/1.3672415 ◽

2012 ◽

Vol 111 (1) ◽

pp. 014102 ◽

Cited By ~ 4

Author(s):

Xinqiang Zhang ◽

Hailing Tu ◽

Yiwen Guo ◽

Hongbin Zhao ◽

Mengmeng Yang ◽

...

Keyword(s):

Thin Films ◽

Atomic Configuration ◽

High K

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Optical Properties and Raman Scattering Investigation of Ag Doped ZnO Thin Film Prepared by Two-Step Solution-Based Deposition Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.773-774.739 ◽

2015 ◽

Vol 773-774 ◽

pp. 739-743

Author(s):

A.N. Afaah ◽

N.A.M. Asib ◽

Aadila Aziz ◽

Ruziana Mohamed ◽

Kevin Alvin Eswar ◽

...

Keyword(s):

Thin Films ◽

Raman Scattering ◽

Ultra Violet ◽

Peak Shift ◽

Zno Thin Films ◽

Zno Films ◽

Deposition Method ◽

Immersion Method ◽

Glass Substrates ◽

Doped Zno

Mist-atomization deposition method was applied in order to grow ZnO nanoparticles on Au-seeded glass substrates acting as seeded template. Ag doped ZnO thin films were deposited on ZnO seeded templates by solution-immersion method. The influence of Ag doping content on the optical and Raman scattering properties of ZnO films were systematically investigated by UV-Vis transmittance measurement measured by ultra-violet visible spectroscopy (UV-Vis) and Raman scattering spectrum measured by Raman spectroscopy under room temperature. From UV-Vis transmittance measurement, the incorporation of Ag dopant to the ZnO makes the transmittance wavelength shifted to the shorter wavelength as compared to the pure ZnO. From Raman spectra, 4 cm-1 downshift is observed in Ag-doped thin films as compared to pure ZnO thin films. This Raman peak shift shows that a tensile stress existed in the Ag-doped ZnO film.

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Incorporation of Iron Cations Into Epitaxial Sapphire Thin Films by CO-Evaporation and Subsequent Thermal Annealing

MRS Proceedings ◽

10.1557/proc-341-321 ◽

1994 ◽

Vol 341 ◽

Cited By ~ 1

Author(s):

Ning Yu ◽

Harriet Kung ◽

Michael Nastasi ◽

DeQuan Li

Keyword(s):

Thin Films ◽

Single Crystal ◽

Thermal Annealing ◽

Rutherford Backscattering Spectrometry ◽

Ultra Violet ◽

Cation Sublattice ◽

Epitaxial Relationship ◽

Cross Sectional ◽

Simple Method ◽

Subsequent Thermal Annealing

AbstractIron-doped sapphire thin films have been successfully epitaxially grown onto sapphire single crystal substrates by electron beam deposition and subsequent thermal annealing. Amorphous A12O3 thin films, about 280–390 nm thick, cation doped with iron have been deposited on [0001] oriented sapphire substrates. Iron doping with cation concentrations (a ratio of Fe content to total cation content) up to 5 at.% can be incorporated into the octahedral sites of Al-cation sublattice during the epitaxial regrowth process at 1000–1400 C, as determined by Rutherford Backscattering Spectrometry and ion channeling measurements. Cross-sectional Transmission Electron Microscopy shows the presence of two distinct regions in the annealed films. One exhibits the epitaxial relationship with the sapphire substrate and the second region has amorphous type of contrast. External optical transmittance measurements in the ultra violet and visible light range have exhibited the absorption associated with Fe3+. This study has demonstrated a simple method of incorporating dopants into single crystal sapphire, which has potential in the fabrications of thin film planar optical waveguiles.

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Formation and Optical Studies of Porous GaN Thin Films via UV-Assisted Electrochemical Etching Approach

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.895.45 ◽

2014 ◽

Vol 895 ◽

pp. 45-50 ◽

Cited By ~ 1

Author(s):

Sook Fong Cheah ◽

Sha Shiong Ng ◽

Fong Kwong Yam ◽

Abu Hassan Haslan ◽

Hassan Zainuriah

Keyword(s):

Thin Films ◽

Potassium Hydroxide ◽

Electrochemical Etching ◽

Ultra Violet ◽

Xenon Lamp ◽

Phonon Modes ◽

Optical Studies ◽

Layer Characteristic ◽

Ir And Raman ◽

Etching Duration

This paper presents the investigation of porous gallium nitride (PGaN) thin films by ultra-violet (UV)-assisted electrochemical etching at various etching durations. The etching process was performed in potassium hydroxide aqueous solution under illumination of 150 W xenon lamp. The surface morphology and cross-section of the PGaN thin films were examined by scanning electron microscopy. Increased etching duration resulted in a more homogeneous pore distribution. Results showed that the etching duration strongly influences the layer characteristic of porous structure. Infrared (IR) and Raman studies were performed to investigate the optical properties of PGaN. IR spectroscopy revealed that the PGaN thin films exhibit distinctive IR spectra as compared to the as-grown GaN thin film. The number of interference fringes in the non-reststrahlen band is correlated to the film thickness of as-grown and PGaN thin films. The Raman measurements clearly reveal two forbidden optical phonon modes observed in all the PGaN thin films. This result indicates the crystal disordering in the films. Additionally, the findings show that the intensity of these forbidden modes becomes stronger with increasing etching duration.

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Luminescent Property of Al2O3:Ce3+ Thin Films

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.23 ◽

2011 ◽

Vol 130-134 ◽

pp. 23-26 ◽

Cited By ~ 1

Author(s):

Shao Feng Yan ◽

Kai Ge Miao

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Flow Rate ◽

Luminescence Intensity ◽

Room Temperature ◽

Luminescent Properties ◽

Cerium Chloride ◽

Medium Frequency ◽

Excitation Spectra ◽

The Relationship

The Al2O3 films doped with Ce3 + were deposited on slides by the medium-frequency reaction magnetron sputtering process, to which the power is constant, Ar flow rate 70 sccm, O2 flow rate 25~45sccm and sputtering time 90min at room temperature. The relationship between the luminescent properties of Al2O3:Ce3 + films and the doped amount of Ce3 + in the films was studied. The presence of Ce3 + and stoichiometry of those films were determined. It was observed that the total luminescence intensity increases and the peak positions are strongly dependent on Ce3+ concentration in the films. The analysis of luminescent excitation spectra showed that the luminance is due to the Ce3+ concentration in the cerium chloride aggregate formed in the films.

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