Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Pulsed laser deposition


Investigation of Structural, Optical and Electrical Properties of ZnO Prepared Thin Film by PLD

Samer. Y. Al-Dabag

Engineering and Technology Journal, 2015, Volume 33, Issue 5, Pages 838-847

In this paper , Zinc Oxide (ZnO) films were grown on glass substrates by Pulsed Laser Deposition (PLD) technique at room temperature under the vacuum pressure of 3×10−3 mbar. Employing a Nd:YAG pulses laser at wavelength 1064nm was used in this technique .The effect of number of laser pulses (200,500 and 800) at annealing temperature450C oon the structural, optical and electrical properties was studied.The structure of the ZnO thin films was examined by X-Ray diffraction (XRD), it was found thatZnO thin films arepolycrystalline with many peaks, and the results of Atomic Force Microscopy (AFM) indicated that all films have grain size around 90 nm.The optical properties concerning the photoluminescence (PL) spectra were studied for the prepared thin film. From the PL, the optical gap of the ZnO thin film was determined. The Hall effect measurements confirmed that the ZnO thin films are n-type , While the number of laser pulses is increasing, the charge carriers concentration (n) increases, and Hall mobility (H) decreases.

Annealing Effect on the Growth of Nanostructured TiO2 Thin Films by Pulsed Laser Deposition (PLD)

Sarmad S.Kaduory; Ali A.Yousif; Adawiya J. Haider; Khaled Z.Yahya

Engineering and Technology Journal, 2013, Volume 31, Issue 4, Pages 460-470

In this work, Nanostructured TiO2 thin films were grown by pulsed laser deposition (PLD) technique on glass substrates at 300 °C. TiO2 thin films were then annealed at 400-600 °C in air for a period of 2 hours. Effect of annealing on the structure, morphology and optical properties were studied. The X-ray diffraction (XRD) and Atomic Force Microscopy (AFM) measurements confirmed that the films grown by this technique have good crystalline tetragonal mixed anatase and rutile phase structure and homogeneous surface. The study also reveals that the RMS value of thin films roughness increased with increasing annealing temperature .The optical properties of the films were studied by UV-VIS spectrophotometer. The optical transmission results shows that the transmission over than ~65% which decrease with the increasing of annealing temperatures. The allowed indirect optical band gap of the films was estimated to be in the range from 3.49 to 3.1 eV. The allowed direct band gap was found to decrease from 3.74 to 3.55 eV with the increase of annealing temperature. The refractive index of the films was found from 2.27 -2.98 at 550nm. The extinction coefficient increase with annealing temperature.

Optical and Structure Properties of MgxZn1-xO Thin Films by Pulsed Laser Deposition

Gehan E. Simon; Adawiya J. Haidar

Engineering and Technology Journal, 2009, Volume 27, Issue 14, Pages 2653-2665

In this study, the optical and structure properties of MgxZn1-xO thin films is reported. The MgxZn1-xO thin films were prepared on Glass substrates by Q-switch second harmonic Nd:YAG laser deposition technigue with wavelength of 532nm from a ZnO target mixed with Mg of (0-0.3) wt% , and the films deposited at temperature (250°C).
The optical properties were characterized by transmittance and absorption spectroscopy measurements. For all the films the average transmission in the U.V (200-900) nm wavelength region was over 85% and the absorption edge shifted to a shorter wavelength as the magnesium concentration increased. The optical energy gap of MgxZn1-xO thin films, measured from transmittance spectra could be controlled between (3.3eV and 4.2eV) by adjusting magnesium concentration. X-ray diffraction was used to investigate the structure of the film. The refractive index of hexagonal MgxZn1-xO thin films decreases with the Mg concentration increase, such as at the wavelength of (500nm) the refractive index decreases from 1.93 to 1.85 as x increase from 0.15 to 0.3. The extinction coefficient and the complex dielectric constant were also investigate.