PULSED LASER DEPOSITION — ABLATION MECHANISM AND APPLICATIONS

2013 ◽  
Vol 22 ◽  
pp. 355-360 ◽  
Author(s):  
M. C. RAO
Keyword(s):  
High Temperature ◽  
Laser Ablation ◽  
Laser Beam ◽  
Pulsed Laser Deposition ◽  
Continuous Wave ◽  
High Temperature Superconductivity ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Wide Range ◽  
Laser Flux

Laser ablation is the process of removing material from a solid surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates. At high laser flux, the material is typically converted to a plasma. Usually, laser ablation refers to removing material with a pulsed laser, but it is possible to ablate material with a continuous wave laser beam if the laser intensity is high enough. In general, the method of pulsed laser deposition (PLD) is simple. Only few parameters need to be controlled during the process. Targets used in PLD are small compared with other targets used in other sputtering techniques. It is quite easy to produce multi-layer film composed of two or more materials. Besides, by controlling the number of pulses, a fine control of film thickness can be achieved. Pulsed-laser deposition has been used to deposit an extraordinarily wide range of materials. Historically, the most significant application of PLD has been in the area of high temperature superconducting thin films. The demonstration that PLD could be used to deposit YBa2Cu3O7-x (YBCO) films with zero resistivity at nearly 85 K sparked a significant amount of high temperature superconductivity research over the past decade and has stimulated research in PLD in general. The most striking limitations of PLD are the generation of particulates during the deposition process and the non uniform coating thickness, when substrates of large area are deposited.

Pulsed laser deposition of oriented V2O5 thin films

2000 ◽  
Vol 15 (10) ◽  
pp. 2249-2265 ◽  
Author(s):  
Jeanne M. McGraw ◽  
John D. Perkins ◽  
Falah Hasoon ◽  
Philip A. Parilla ◽  
Chollada Warmsingh ◽  
...  
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Oxygen Pressure ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Glass Substrates ◽  
Wide Range ◽  
Phase Pure ◽  
Amorphous Quartz ◽  
Quartz Substrates

We have found that by varying only the substrate temperature and oxygen pressure five different crystallographic orientations of V2O5 thin films can be grown, ranging from amorphous to highly textured crystalline. Dense, phase-pure V2O5 thin films were grown on SnO2/glass substrates and amorphous quartz substrates by pulsed laser deposition over a wide range of temperatures and oxygen pressures. The films' microstructure, crystallinity, and texturing were characterized by electron microscopy, x-ray diffraction, and Raman spectroscopy. Temperature and oxygen pressure appeared to play more significant roles in the resulting crystallographic texture than did the choice of substrate. A growth map summarizes the results and delineates the temperature and O2 pressure window for growing dense, uniform, phase-pure V2O5 films.

Pulsed Laser Deposition History and Laser-Target Interactions

MRS Bulletin ◽  
1992 ◽  
Vol 17 (2) ◽  
pp. 30-36 ◽  
Author(s):  
Jeff Cheung ◽  
Jim Horwitz
Keyword(s):  
Thin Film ◽  
Laser Beam ◽  
Pulsed Laser Deposition ◽  
Mechanical Energy ◽  
Pulsed Laser ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Laser Deposition ◽  
Small Branch ◽  
The Impact

The laser, as a source of “pure” energy in the form of monochromatic and coherent photons, is enjoying ever increasing popularity in diverse and broad applications from drilling micron-sized holes on semiconductor devices to guidance systems used in drilling a mammoth tunnel under the English Channel. In many areas such as metallurgy, medical technology, and the electronics industry, it has become an irreplaceable tool.Like many other discoveries, the various applications of the laser were not initially defined but were consequences of natural evolution led by theoretical studies. Shortly after the demonstration of the first laser, the most intensely studied theoretical topics dealt with laser beam-solid interactions. Experiments were undertaken to verify different theoretical models for this process. Later, these experiments became the pillars of many applications. Figure 1 illustrates the history of laser development from its initial discovery to practical applications. In this tree of evolution, Pulsed Laser Deposition (PLD) is only a small branch. It remained relatively obscure for a long time. Only in the last few years has his branch started to blossom and bear fruits in thin film deposition.Conceptually and experimentally, PLD is extremely simple, probably the simplest among all thin film growth techniques. Figure 2 shows a schematic diagram of this technique. It uses pulsed laser radiation to vaporize materials and to deposit thin films in a vacuum chamber. However, the beam-solid interaction that leads to evaporation/ablation is a very complex physical phenomenon. The theoretical description of the mechanism is multidisciplinary and combines equilibrium and nonequilibrium processes. The impact of a laser beam on the surface of a solid material, electromagnetic energy is converted first into electronic excitation and then into thermal, chemical, and even mechanical energy to cause evaporation, ablation, excitation, and plasma formation.

scholarly journals Electroanalytical Performance of Nitrogen-Doped Graphene Films Processed in One Step by Pulsed Laser Deposition Directly Coupled with Thermal Annealing

Materials ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 666 ◽  
Author(s):  
Florent Bourquard ◽  
Yannick Bleu ◽  
Anne-Sophie Loir ◽  
Borja Caja-Munoz ◽  
José Avila ◽  
...  
Keyword(s):  
High Temperature ◽  
Pulsed Laser Deposition ◽  
Graphene Film ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Synthesis Process ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene ◽  
One Step

Graphene-based materials are widely studied to enable significant improvements in electroanalytical devices requiring new generations of robust, sensitive and low-cost electrodes. In this paper, we present a direct one-step route to synthetize a functional nitrogen-doped graphene film onto a Ni-covered silicon electrode substrate heated at high temperature, by pulsed laser deposition of carbon in the presence of a surrounding nitrogen atmosphere, with no post-deposition transfer of the film. With the ferrocene methanol system, the functionalized electrode exhibits excellent reversibility, close to the theoretical value of 59 mV, and very high sensitivity to hydrogen peroxide oxidation. Our electroanalytical results were correlated with the composition and nanoarchitecture of the N-doped graphene film containing 1.75 at % of nitrogen and identified as a few-layer defected and textured graphene film containing a balanced mixture of graphitic-N and pyrrolic-N chemical functions. The absence of nitrogen dopant in the graphene film considerably degraded some electroanalytical performances. Heat treatment extended beyond the high temperature graphene synthesis did not significantly improve any of the performances. This work contributes to a better understanding of the electrochemical mechanisms of doped graphene-based electrodes obtained by a direct and controlled synthesis process.

scholarly journals Oxidation of ablated silicon during pulsed laser deposition in a background gas with different oxygen partial pressures

2019 ◽  
Vol 196 ◽  
pp. 00008
Author(s):  
Sergey V. Starinskiy ◽  
Alexey A. Rodionov ◽  
Yuri G. Shukhov ◽  
Alexander V. Bulgakov
Keyword(s):  
Optical Properties ◽  
Laser Beam ◽  
Pulsed Laser Deposition ◽  
Oxidation State ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Oxidation Degree ◽  
Total Oxidation ◽  
Partial Pressures ◽  
Background Gas

We have analysed changes in the oxidation state of SiOx films produced by pulsed laser deposition in a background gas with different partial pressures of oxygen. The optical properties of the films in IR range are shown to be close to those of SiO2 while the total oxidation degree is considerably less than 2. It is suggested that the film consists of oxidized and unoxidized regions due to preferential oxidation of the periphery of the silicon ablation plume during expansion. These regions are overlapping in the film if the laser beam is scanned on the target.

Annealing behaviors of structural, interfacial and optical properties of HfO2 thin films prepared by plasma assisted reactive pulsed laser deposition

2010 ◽  
Vol 25 (4) ◽  
pp. 680-686 ◽  
Author(s):  
Zhifeng Ying ◽  
Wentao Tang ◽  
Zhigao Hu ◽  
Wenwu Li ◽  
Jian Sun ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Optical Properties ◽  
High Temperature ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
High Temperature Annealing ◽  
Good Thermal Stability ◽  
Transmission Measurements ◽  
Deposited Films

The structure and properties of HfO2 films deposited by plasma assisted reactive pulsed laser deposition and annealed in N2 were studied upon thermal annealing as well as the evaluation of thermal stability by Fourier transform infrared spectroscopy, spectroscopic ellipsometry, and optical transmission measurements. The as-deposited HfO2 films appear predominantly monoclinic with an amorphous matrix which becomes crystallized after high-temperature annealing. No interfacial SiOx is observed for the as-deposited films on Si. The deposited HfO2 films exhibit good thermal stability and show excellent transparency in a wide spectral range with optical band gap energies of 5.65–5.73 eV depending on annealing temperature. An improvement in the optical properties by high-temperature annealing is also observed.

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