INFLUENCE OF ARGON PRESSURE ON MICROSTRUCTURE AND OPTICAL PROPERTIES OF Zn0.9Se:Co0.1 THIN FILMS PREPARED BY PULSED LASER DEPOSITION

Zn[Formula: see text]Se:Co[Formula: see text] thin films were deposited on sapphire (Al2O3) substrates in argon atmosphere at various gas pressures by pulsed laser deposition. Influence of argon pressure on the thickness, surface morphology, crystal structure and optical properties of the thin films were investigated by various diagnosis tools. It was found that these physical properties were correlated to the argon pressure and appeared like a mutation between the pressure of 2[Formula: see text]Pa and 4[Formula: see text]Pa. As the deposition pressure changed from 2[Formula: see text]Pa to 4[Formula: see text]Pa, the collision probability between ablated species and argon molecule was increased, which resulted in the transformation of the deposition type from sputter effect to adsorption effect and the mutation of film thickness and structure. These in turn influence the transmission range and band gap of the films. All of the results suggest that the ambient pressure is a very important factor to the deposition of Zn[Formula: see text]Se:Co[Formula: see text] films by PLD.

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Effect of Annealing on Structural and Optical Properties of Pulsed Laser Deposited Titanium Dioxide Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.67.65 ◽

2009 ◽

Vol 67 ◽

pp. 65-70 ◽

Cited By ~ 1

Author(s):

Gaurav Shukla ◽

Alika K. Khare

Keyword(s):

Thin Films ◽

Optical Properties ◽

Pulsed Laser Deposition ◽

Annealing Temperature ◽

Ambient Pressure ◽

Pulsed Laser ◽

Laser Deposition ◽

Tio2 Thin Films ◽

Post Annealing ◽

Post Annealing Temperature

TiO2 is a widely studied material for many important applications in areas such as environmental purification, photocatalyst, gas sensors, cancer therapy and high effect solar cell. However, investigations demonstrated that the properties and applications of titanium oxide films depend upon the nature of the crystalline phases present in the films, i.e. anatase and rutile phases. We report on the pulsed laser deposition of high quality TiO2 thin films. Pulsed Laser deposition of TiO2 thin films were performed in different ambient viz. oxygen, argon and vacuum, using a second harmonic of Nd:YAG laser of 6 ns pulse width. These deposited films of TiO2 were further annealed for 5hrs in air at different temperatures. TiO2 thin films were characterized using x-ray diffraction, SEM, photoluminescence, transmittance and reflectance. We observed effect of annealing over structural, morphological and optical properties of TiO2 thin films. The anatase phase of as-deposited TiO2 thin films is found to change into rutile phase with increased annealing temperature. Increase in crystalline behaviour of thin films with post-annealing temperature is also observed. Surface morphology of TiO2 thin films is dependent upon ambient pressure and post- annealing temperature. TiO2 thin films are found to be optically transparent with very low reflectivity hence will be suitable for antireflection coating applications.

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