Experimental Investigation of Pulsed Laser Deposition Based on a Compressible Flow Framework

Author(s):  
Biqing Sheng ◽  
Zhaoyan Zhang

Pulsed laser deposition (PLD) is a popular technique for creating thin films. The film characteristics are directly related to the kinetic energy of the laser-induced plume. According to the theory of transient shock wave expansion during laser ablation, laser-induced plume properties are strongly affected by laser intensity as well as ambient temperature, pressure, and gas species. This theory leads to the development of PLD strategies to properly optimize the PLD parameters. The experiments were carried out to deposit diamond-like carbon (DLC) thin films under different ambient temperature, pressure and gas species. The deposited DLC thin films were characterized by Raman spectroscopy. Experimental results showed that the thin film quality can be improved by decreasing the ambient temperature, increasing the ambient pressure and using ambient gases with low molecular weight. Experimental results agree well with the theoretical prediction.

2009 ◽  
Vol 67 ◽  
pp. 65-70 ◽  
Author(s):  
Gaurav Shukla ◽  
Alika K. Khare

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.


1997 ◽  
Vol 472 ◽  
Author(s):  
M.A. El Khakani ◽  
M. Chaker

ABSTRACTReactive pulsed laser deposition has been used to deposit IrO2 thin films on both SiO2 and fused quartz substrates, by ablating a metal iridium target in oxygen atmosphere. At a KrF laser intensity of about 1.7 × 109 W/cm2, IrO2 films were deposited at substrate deposition temperatures ranging from room-temperature to 700 °C under an optimum oxygen ambient pressure of 200 mTorr. The structure, morphology, electrical resistivity and optical transmission of the deposited films were characterized as a function of their deposition temperature (Td). High quality IrO2 films are obtained in the 400–600 °C deposition temperature range. They are polycrystalline with preferred orientations, depending on the substrate, and show a dense granular morphology. At a Td as low as 400 °C, highly conductive IrO2 films with room-temperature resistivities as low as (42±6) μΩ cm are obtained. Over the 300–600 °C Td range, the IrO2 films were found to exhibit a maximum optical transmission at 450 °C (∼ 45 % at 500 nm for 80 nm-thick films).


2010 ◽  
Vol 25 (10) ◽  
pp. 1886-1889 ◽  
Author(s):  
T. Ohnishi ◽  
B.T. Hang ◽  
X. Xu ◽  
M. Osada ◽  
K. Takada

Thin films of c-axis-oriented LiCoO2 were epitaxially grown by pulsed laser deposition (PLD). The ablation laser conditions greatly affect the crystal quality of the epitaxial LiCoO2 thin films. In addition, high-quality LiCoO2 thin films were found to grow without any impurity phases under relatively low oxygen partial pressure, although high pressure had been often selected to suppress the formation of Co3O4 with a lower valence state as an impurity. This result clearly indicates that the ablation laser conditions are an essential growth parameter, and that composition control is indispensable to grow high-quality complex compound thin films by PLD.


2001 ◽  
Vol 117 (11) ◽  
pp. 673-677 ◽  
Author(s):  
P. Misra ◽  
P. Bhattacharya ◽  
K. Mallik ◽  
S. Rajagopalan ◽  
L.M. Kukreja ◽  
...  

Author(s):  
Boscope M. K. Sze ◽  
C. N. Wong ◽  
K. H. Wong

Thin films of Ce0.8Gd0.2O2 and Ce0.8Sm0.2O2 oxide electrolytes have been fabricated by pulsed laser deposition on (100)LaAlO3 substrates at temperature from 300 °C to 700 °C and under 100 mTorr oxygen ambient pressure. The crystal structure, crystallinity and lattice parameters of the as-deposited films are investigated by X-ray diffraction. High quality epitaxial and polycrystalline films are obtained at different growth conditions. We have made impedance measurements on these films in the temperature range from 300 °C to 850 °C. Our results reveal a mark increase in the ionic conductivity of these films in comparison with those of the corresponding bulk materials. The observed enhancements are closely related to the crystallinity of the films. Conductivities of 0.1 S/cm or higher for Ce0.8Gd0.2O2 and Ce0.8Sm0.2O2 are obtained at 500 °C. We have demonstrated that in utilizing these thin films solid oxide fuel cells operating at below 500 °C are possible.


2016 ◽  
Vol 165 ◽  
pp. 95-98 ◽  
Author(s):  
Hiroaki Nishikawa ◽  
Tsukasa Hasegawa ◽  
Akiko Miyake ◽  
Yuichiro Tashiro ◽  
Yoshiya Hashimoto ◽  
...  

AIP Advances ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 075321
Author(s):  
Wenhao Luo ◽  
Liangjie Li ◽  
Yingbang Yao ◽  
Bing Luo ◽  
Fuzeng Zhang ◽  
...  

2006 ◽  
Vol 44 (2) ◽  
pp. 147-154 ◽  
Author(s):  
Yoshiki Nakata ◽  
Tatsuo Okada ◽  
Mitsuo Maeda ◽  
Sadao Higuchi ◽  
Kiyotaka Ueda

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