Effect of Annealing Temperatures on the Structural, Optical Properties of Tungsten Selenide Thin Films

In this work, we study the optical properties of the Nickel doped cupric oxide Ni-CuO thin films with Ni various doping concentrations (0, 20, 30, 50, 70, and 80%), at two different annealing temperatures; 200 and 400 °C. The absorbance and optical bandgap for the films are calculated and compared. We find that all films exhibit clear peaks in the visible range, with the increase in the absorptivity via increasing both annealing and Ni concentration. We also find that the annealing affects the shape of the absorbance peaks to be narrowed and blue shifted. Investigation on the direct bandgap energy shows that all films exhibit large direct gap; ranging from 3.87 to 4.01 eV. For non-annealed films, direct bandgap increases with increasing the Ni concentration, while for the annealed samples, the direct bandgap generally decreases by annealing, and with increasing the doping concentration. For the indirect bandgap analysis, the calculated values of the bandgap are ranging from 0.62 to 1.96 eV. We find that for non-annealed films, the indirect bandgap increases with increasing the doping concentration, while after annealing, the bandgap decreases with increasing the doping concentration for the annealing at 200 and 400 °C, with more decreasing in the gap at 400 °C.

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Determination of growth regimes of Pd nanostructures on c-plane sapphire by the control of deposition amount at different annealing temperatures

Physical Chemistry Chemical Physics ◽

10.1039/c7cp01410d ◽

2017 ◽

Vol 19 (23) ◽

pp. 15084-15097 ◽

Cited By ~ 10

Author(s):

Sundar Kunwar ◽

Mao Sui ◽

Puran Pandey ◽

Quanzhen Zhang ◽

Ming-Yu Li ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Solid State ◽

Structural Evolution ◽

Pd Nanoparticles ◽

Annealing Temperatures ◽

Deposition Amount ◽

Sputter Deposited ◽

Different Thickness

Semi-spherical and irregular Pd nanoparticles and voids are fabricated on sapphire(0001) by the solid-state dewetting of sputter-deposited Pd thin films at different thickness and temperature. The structural evolution, surface morphology transformation and optical properties of Pd nanostructures are probed.

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Optical Properties of Nanostructured Zinc Oxides Deposited on Silicon Substrates

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.1132 ◽

2011 ◽

Vol 312-315 ◽

pp. 1132-1136 ◽

Cited By ~ 4

Author(s):

Mohamad Hafiz Mamat ◽

Zuraida Khusaimi ◽

Mohamad Mahmood Rusop

Keyword(s):

Thin Films ◽

Optical Properties ◽

Spin Coating ◽

Sol Gel ◽

Zno Thin Films ◽

Silicon Substrates ◽

Annealing Temperatures ◽

Uv Emission ◽

Zinc Oxides ◽

Optically Transparent

Nanostructured zinc oxide (ZnO) thin films were prepared through sol-gel method and spin-coating technique. ZnO thin films then were annealed at temperature of 350°C, 400°C, 450°C and 500°C. The thin films were characterized using field emission scanning electron microscope (FESEM), UV-VIS-NIR spectrophotometer and photoluminescence (PL) spectrofluorometer for morphology and optical properties study. The morphology study indicates that the particle size of ZnO increased with annealing temperatures. All thin films are optically transparent (~ 80 % in transmittance) in the visible light-NIR region. PL spectra reveal improved UV emission with annealing temperatures up to 500°C.

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