Boron and Phosphorus Ion Implantation In a-SixC1−x:H Thin Films

ABSTRACTIn this paper we report results on the optoelectronic and structural properties of device-quality a-SixC1−x:H intrinsic films with energy gap of 1.94 eV and Urbach energy of 70 MeV, grown by PECVD of SiH4+CH4 Mixture, which have been doped by means of boron or phosphorus ion implantation. Doping levels varied in the range 1018 to 5×1020 atoms/cm3. The behaviour of electrical characteristics, as well as energy gap and defect density, Measured on samples annealed in the range 150–400°C, showed that the optimum annealing temperature for the recovery of radiation damage is in the range 250–270°C independent of the implanted dose. Our results also show that after ion implantation and annealing, an increase of the SiH bonds concentration is detected, which is associated to a decrease of the contribution of SiH2, SiCH3, and SiCH vibrations in IR spectra.

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Annealing Temperature Dependence of Optical Properties of Sol-Gel ZnO Thin Films with Different Sol Aging Time

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.48.211 ◽

2017 ◽

Vol 48 ◽

pp. 211-217 ◽

Cited By ~ 2

Author(s):

Ji Tao Li ◽

Ding Yu Yang ◽

Xing Hua Zhu

Keyword(s):

Thin Films ◽

Optical Properties ◽

Aging Time ◽

Annealing Temperature ◽

Urbach Energy ◽

Energy Gap ◽

Sol Gel ◽

Zno Thin Films ◽

Zno Films ◽

Ultraviolet Emission

ZnO thin films on glass substrates have been successfully fabricated by sol-gel method for various aging time and annealing temperature. X-ray diffraction (XRD) patterns showed the crystallites at (100), (002) and (101) plane of hexagonal wurtzite structure. Atomic force microscope (AFM) images were used to investigate the surface morphology. The transmittance, energy gap, Urbach energy and photoluminescence (PL) of samples were investigated to explore the effects of annealing temperature on optical properties of ZnO thin films under different sol aging time. The transmittance spectra of thin films aged for 24 hours and 48 hours revealed the enhanced transmittance in visible region as rising annealing temperature, also, the optical band gap of the samples increased and Urbach energy decreased. The photoluminescence (PL) spectra of samples aged for 24 hours and 48 hours were studied and found the increased ultraviolet emission at ~387 nm, and various decreased visible emissions with rising annealing temperature. Nevertheless, the excessive sol aging time for 72 hours deteriorated the optical characteristics of thin films, resulting in that transmittance, energy gap and ultraviolet emission declined, and visible emissions increased with rising annealing temperature. The optical performances of the ZnO films aged for different time have no the same dependence of annealing temperature.

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The role of annealing temperature on the optical energy gap and Urbach energy of Se:2%Sb thin films

Baghdad Science Journal ◽

10.21123/bsj.5.2.249-252 ◽

2008 ◽

Vol 5 (2) ◽

pp. 249-252

Author(s):

Baghdad Science Journal

Keyword(s):

Thin Films ◽

Annealing Temperature ◽

Urbach Energy ◽

Energy Gap ◽

Localized States ◽

Structural Defects ◽

Indirect Transition ◽

Optical Energy Gap ◽

Optical Energy

The optical energy gap(Eopt) and the width of the tails of localized states in the band gap (?E) for Se:2%Sb thin films prepared by thermal co-evaporation method as a function of annealing temperature are studied in the photon energy range ( 1 to 5.4)eV.Se2%Sb film was found to be indirect transition with energy gap of (1.973,2.077, 2.096, 2.17) eV at annealing temperature (295,370,445,520)K respectively. The Eopt and ?E of Se:2%Sb films as a function of annealing temperature showed an increase in Eopt and a decrease in ?E with increasing the annealing temperature. This behavior may be related to structural defects and dangling bonds.

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Simultaneous Relaxation of Network and Defects in Silicon-Implanted a-Si:H

MRS Proceedings ◽

10.1557/proc-377-173 ◽

1995 ◽

Vol 377 ◽

Cited By ~ 4

Author(s):

J. Nakata ◽

S. Sherman ◽

S. Wagner ◽

P. A. Stolk ◽

J. M. Poate

Keyword(s):

Electronic Transport ◽

Annealing Temperature ◽

Urbach Energy ◽

Defect Density ◽

Dark Conductivity ◽

Equilibrium Theory ◽

Hopping Conduction ◽

Dangling Bond ◽

Bond Density ◽

Additional Illumination

ABSTRACTWe report extensive optical and electronic transport data on silicon-implanted a-Si:H, annealed in steps in the dark or with additional illumination. All measured properties relax gradually with increasing annealing temperature. The dark conductivity of the as-implanted film is dominated by hopping conduction via midgap defects. This channel is pinched off during the initial stages of annealing. The midgap defect density and the Urbach energy follow an annealing path that agrees qualitatively with the trajectory postulated by the equilibrium theory of the dangling-bond density. Therefore, the silicon network and the defect density equilibrate continuously during network relaxation.

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The Effect of Substrate Temperature on the Band Transition, Cauchy Dispersion and Urbach Energy of Nanostructure CdO Thin Films

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.58.83 ◽

2015 ◽

Vol 58 ◽

pp. 83-89

Author(s):

Muneer H. Jadduaa ◽

Zainab Ali Harbi ◽

Nadir F. Habubi

Keyword(s):

Thin Films ◽

Substrate Temperature ◽

Urbach Energy ◽

Energy Gap ◽

Chemical Spray Pyrolysis ◽

Optical Parameters ◽

Optical Energy Gap ◽

Substrate Temperature Increase ◽

Band Transition ◽

Cdo Thin Films

Thin films of CdO were prepared by chemical spray pyrolysis (CSP) . The effect of different temperature substrate (300,350,400,450 and 500) °C on some optical parameters has been studied . The transmittance and the optical energy gap were increased from (2.503-2.589) eV ,on the contrary of the rest parameters such as refractive index , real and imaginary parts of dielectric constant and Urbach energy which they were decreased as the substrate temperature increase.

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Effect of Annealing Temperature on Structural Properties of Ba0.9Er0.1TiO3 Thin Films

Proceedings of the Second International Conference on the Future of ASEAN (ICoFA) 2017 – Volume 2 ◽

10.1007/978-981-10-8471-3_74 ◽

2018 ◽

pp. 757-765

Author(s):

Zeen Vee Ooi ◽

Ala’Eddin Ahmad Saif

Keyword(s):

Thin Films ◽

Structural Properties ◽

Annealing Temperature

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Microstructure and Mechanical Properties of Chromium Carbide Coatings Deposited by Magnetron Sputtering Technique

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.397.118 ◽

2019 ◽

Vol 397 ◽

pp. 118-124

Author(s):

Linda Aissani ◽

Khaoula Rahmouni ◽

Laala Guelani ◽

Mourad Zaabat ◽

Akram Alhussein

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Magnetron Sputtering ◽

Structural Properties ◽

Annealing Temperature ◽

Diffusion Mechanism ◽

X Ray Diffraction ◽

Chromium Carbides ◽

X Ray ◽

Mechanical And Structural Properties

From the hard and anti-corrosions coatings, we found the chromium carbides, these components were discovered by large studies; like thin films since years ago. They were pointed a good quality for the protection of steel, because of their thermal and mechanical properties for this reason, it was used in many fields for protection. Plus: their hardness and their important function in mechanical coatings. The aim of this work joins a study of the effect of the thermal treatment on mechanical and structural properties of the Cr/steel system. Thin films were deposited by cathodic magnetron sputtering on the steel substrates of 100C6, contain 1% wt of carbon. Samples were annealing in vacuum temperature interval between 700 to 1000 °C since 45 min, it forms the chromium carbides. Then pieces are characterising by X-ray diffraction, X-ray microanalysis and scanning electron microscopy. Mechanical properties are analysing by Vickers test. The X-ray diffraction analyse point the formation of the Cr7C3, Cr23C6 carbides at 900°C; they transformed to ternary carbides in a highest temperature, but the Cr3C2 doesn’t appear. The X-ray microanalysis shows the diffusion mechanism between the chromium film and the steel sample; from the variation of: Cr, Fe, C, O elements concentration with the change of annealing temperature. The variation of annealing temperature shows a clean improvement in mechanical and structural properties, like the adhesion and the micro-hardness.

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Investigation of Optical Properties of Aluminium Doped Zinc Oxide Thin Films Deposited by Magnetron Sputtering

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.446-447.259 ◽

2013 ◽

Vol 446-447 ◽

pp. 259-262

Author(s):

J.H. Gu ◽

T. Zhang ◽

Z.Y. Zhong ◽

C.Y. Yang ◽

J. Hou

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Refractive Index ◽

Magnetron Sputtering ◽

Structural Properties ◽

Energy Gap ◽

Dispersion Model ◽

Argon Pressure ◽

Optical Energy Gap ◽

Characterization Methods

Aluminium doped zinc oxide (AZO) thin films were prepared by magnetron-sputtering. The optical and structural properties of the films were investigated by optical transmission spectra and X-ray diffraction (XRD) measurements, respectively. The results indicate that the AZO films have hexagonal wurtzite structure with highly c-axis preferred orientation. The optical and structural properties of the films are observed to be subjected to the argon pressure. The AZO film prepared at the argon pressure of 0.5 Pa exhibits the largest crystallite size and the highest average visible transmittance. Also, the refractive index and optical energy-gap of the films were determined by optical characterization methods. The dispersion behavior of the refractive index was studied using the Sellmeier’s dispersion model.

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