Optical properties of porous LDPE films

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Linear and nonlinear optical properties of ZnO thin films deposited by pulsed laser deposition

The structural, electrical, and optical properties of SnO2 films prepared by reactive magnetron sputtering: Influence of substrate temperature and O2 flow rate

Effect of laser repetition frequency on the structural and optical properties of ZnO thin films by PLD

Optical properties of ZnS thin films coated with organic dye extract on different Zn2+ concentrations from ZnSO4 are presented in this study. The effects of concentration and post-deposition annealing temperatures on the optical properties of the films were investigated. Aqueous dye extract-coated ZnS nanocrystals, were prepared by a simple and low-cost chemical bath deposition method. Results obtained revealed that optical properties of the films were modified by concentration and post-deposition annealing temperature. Increasing concentration reduced the transparency of the films. Annealing increased the transparency of the films except for films deposited with 0.1M concentration of ZnSO4. In general, the heat-treated layers were found to transmit better than the as-deposited layers. The analysis of energy band gap showed a reduction in band gap with increasing Zn2+ concentration of the as-deposited films. It also indicated that post-deposition annealing, increased energy band gap except for films deposited with 0.1M concentration of ZnSO4. The relationship between the energy band gap with both concentration and post-deposition annealing fit into the quadratic model with high R2 values. The range of values of 3.889–3.981eV recorded for the band gaps is within the range for application in diverse solar architecture and optoelectronic devices.

This paper details the development of appropriate techniques for quantifying and comparing the optical properties of transparent polymer films used in in-mould decoration (IMD) and the effects of heat and strain on these properties. Currently there are no approved methods for optical characterization of transparent films, with most techniques being based on reflectance measurement of printed materials for the graphic arts industry. Original experimentation was therefore required in order to characterize the optical properties of transparent polymer films used in IMD or similar applications and to predict the changes in appearance during the forming process. A range of measurement techniques was utilized to characterize the films and their interaction with light in terms of light scattering and transmission. As a result of the investigation, the optical properties of these films can now be quantified and the changes due to the different mechanisms of softening and crystallization can be separately distinguished.

Effect of oxygen pressure on the structural and optical properties of ZnO thin films on Si (111) by PLD

Effect of the variation of temperature on the structural and optical properties of ZnO thin films prepared on Si (1 1 1) substrates using PLD

Some physical properties of copper oxide films: The effect of substrate temperature

Sol–gel spin coating derived cadmium oxide semiconductor thin films: Effect of Lutetium contribution

Optical, electrical and photoelectrical properties of nanocrystalline cadmium selenide films for photosensor applications

CuxZn1-xS (CZS) Nano crystallized thin films with (x=0.25,0.5,0.75) were grown from alloy by thermal evaporation technique on glasses substrates at room temperature in a vacuum ∼ 2 × 10 −5 mbar with 450±20 nm thickness. The Cu content concentration effects on structure, morphology besides optically property of these films were investigated. X-ray diffraction (XRD) technique and Atomic force microscopy (AFM) were used to investigation the structural and morphological properties of CuxZn1-xS films. XRD analysis offered that these films had poly crystalline hexagonal structure with preferred orientation along (201) plane and mixed of of CuS-ZnS structure. The crystallites size changing with Cu concentration were found as (4.12, 5.5, 8.4) nm respectively. Using AFM measurements to investigate morphological properties of these films, the grain size for CuxZn1-xS films differs with Cu content thru uniform distribution. UV-Vis absorption spectroscopy was used to investigation the optical characterization of CuxZn1-xS films as a function of Cu content. The direct band gap values of these films were found decrease with increasing Cu content as (2.45, 2.4, and 2.3) eV respectively and the optical constant affected with Cu content. The CuxZn1-xS films have suitable optical characteristics which can used it for solar cell applications.

Doping effects on electrical and optical properties of spin-coated ZnO thin films

This investigation deals with the effect of temperature on the optical and morphological properties of Zinc Oxide thin films prepared by radio-Frequency (RF) magnetron sputtering technique. In the present work, zinc oxide (ZnO) thin films have been deposited on glass substrates from 50°C to 300°C by radio frequency magnetron sputtering. The effects of deposition temperature on the crystallization behaviour and optical properties of the films have been studied. The thin films were characterized using Ultraviolet Visible Spectroscopy (UV-VIS), Field Emission Scanning Electron Microscopy (FESEM) and X-ray Diffraction Analysis (XRD). From the UV-VIS testing, the average transmission percentage of the films is between 80-95% for all deposition temperatures meanwhile the energy gap of ZnO thin films varies from 3.26 eV to 3.35 eV which is not much different from the theoretical value. Also, the grain size is getting smaller from 3.886nm, 3.216nm, 3.119nm and 3.079nm with respect to the increasing deposition temperature 50°C, 100°C, 200°C and 300°C respectively whereas the average grain size per intercept value is increasing. The patterns of the peak were about the same for all deposition temperature where the thin films have polycrystalline hexagonal wurtzite structure with the orientation perpendicular (002) to the substrate surface (c-axis orientation) at 34.5(2θ).

Titanyl phthalocyanine (TiOPc) is a metal phthalocyanine compound with interesting electronic and catalytic properties, making it useful in various applications. This study investigates the effects of thermal annealing on the optical and dielectric properties of vacuum-evaporated TiOPc films. The optical and structural characteristics were examined before and after annealing. FTIR spectra show a correlation between the peak positions of the films before and after the annealing process. Additionally, the spectra of the annealed sample show a decrease in C=O and the formation of a coordination bond between the Ti dopant and the phthalocyanine molecule. X-ray diffraction shows an amorphous behavior before and after annealing for TiOPc films. The AFM images show the presence of peaks and valleys of varied sizes. This leads to enhanced light trapping and scattering, improving light absorption and optical properties of the film. Thermal annealing at 473 K for 2 h resulted in a significant reduction in the optical energy gap, with E g1 decreasing by approximately 7% (from 1.58 eV to 1.47 eV) and E g2 by about 6% (from 3.0 eV to 2.83 eV), which indicates the thermal stability of these films. Moreover, the real part of dielectric constants reached appreciable improvements of about 30% at low frequencies. These changes are ascribed to the decreased structural defects and enhanced molecular ordering induced by annealing. The thermal stability of TiOPc films and improvement in the performance of optoelectronic devices such as photodetectors and optical switches by applying TiOPc films can be understood from these explorations. Moreover, the simple and cost-effective vacuum evaporation and annealing fabrication enable large-scale industrial production that would be attractive for application engineers to fully utilize these films in practice.