Search results for "Pulsed"
showing 10 items of 305 documents
Fabrication of superconducting tantalum nitride thin films using infra-red pulsed laser deposition
2013
We report the successful fabrication of superconducting tantalum nitride (TaN) thin films using a pulsed laser deposition technique with 1064 nm radiation. Films with thickness $ \sim $ 100 nm deposited on MgO (100) single crystals and on oxidized silicon (SiO$_{2} $) substrates exhibited a superconducting transition temperature of $\sim $ 8 K and 6 K, respectively. The topography of these films were investigated using atomic force and scanning electron microscopy, revealing fairly large area particulate free and smooth surfaces, while the structure of the films were investigated using standard $ \theta -2 \theta $ and glancing angle X-ray diffraction techniques. For films grown on MgO a fa…
Pulsed Direct liquid Injection ALD of TiO2 Films Using Titanium Tetraisopropoxide Precursor
2013
Abstract TiO 2 thin films are grown by pulsed direct liquid injection atomic layer deposition with rapid thermal heating using titanium tetraisopropoxide and water vapor as precursors. The ALD growth rate is constant in the saturation zone range 35-47 ms at the temperature deposition of 280 °C. The TiO 2 growth rate of 0.018 nm/cycle was achieved in a self-limited ALD mode. SEM and AFM analysis showed the as-deposited films have a smooth surface with a low roughness. XPS analysis exhibited the stoichiometry of TiO 2 in the homogenous depth composition.
Laser irradiation of ZnO:Al/Ag/ZnO:Al multilayers for electrical isolation in thin film photovoltaics
2013
Laser irradiation of ZnO:Al/Ag/ZnO:Al transparent contacts is investigated for segmentation purposes. The quality of the irradiated areas has been experimentally evaluated by separation resistance measurements, and the results are complemented with a thermal model used for numerical simulations of the laser process. The presence of the Ag interlayer plays two key effects on the laser scribing process by increasing the maximum temperature reached in the structure and accelerating the cool down process. These evidences can promote the use of ultra-thin ZnO:Al/ Ag/ZnO:Al electrode in large-area products, such as for solar modules. © 2013 Crupi et al.; licensee Springer.
WS2 2D Semiconductor Down to Monolayers by Pulsed-Laser Deposition for Large-Scale Integration in Electronics and Spintronics Circuits
2020
International audience; We report on the achievement of a large-scale tungsten disulfide (WS2) 2D semiconducting platform derived by pulsed-laser deposition (PLD) on both insulating substrates (SrTiO3), as required for in-plane semiconductor circuit definition, and ferromagnetic spin sources (Ni), as required for spintronics applications. We show thickness and phase control, with highly homogeneous wafer-scale monolayers observed under certain conditions, as demonstrated by X-ray photoelectron spectroscopy and Raman spectroscopy mappings. Interestingly, growth appears to be dependent on the substrate selection, with a dramatically increased growth rate on Ni substrates. We show that this 2D…
In situ monitoring of pulsed laser indium–tin-oxide film deposition by optical emission spectroscopy
2001
We performed optical emission spectroscopy to monitor the plasma produced during the ablation of indium-tin-oxide targets under different oxygen pressure conditions using a pulsed UV laser. Molecular bands of InO were identified in the fluorescent spectra produced by pulsed laser ablation. InO line monitoring allowed obtaining the optimal conditions for good-quality ITO film deposition. We demonstrated that it is possible to correlate InO line spectroscopic parameters with the conditions required to fabricate a high-conductivity and high-transparent ITO thin film. In particular, low resistivity (10-4 to 10-3 Ω cm) was obtained in films deposited at room temperature by regulating oxygen pres…
NEUTRON IRRADIATION EFFECTS IN PZ and PZT THIN FILMS
2005
ABSTRACT Neutron irradiation effects on highly oriented antiferroelectric PbZrO3 (PZ) and ferroelectric PbZr0.53Ti0.47O3 (PZT) thin films are investigated in view of their possible application as a temperature sensitive element in a new bolometer system for fusion devices like ITER. All investigated thin films were prepared by a sol-gel technique and by pulsed laser deposition (PLD) respectively. The dielectric properties were investigated in a frequency range from 1 to 250 kHz and at temperatures up to 400°C, prior to and after irradiation to a neutron fluence of 3 * 1022 m−2 (E > 0.1 MeV). After irradiation, the films were anneald in several steps up to 400°C in order to remove the radiat…
Transparent amorphous memory cell: A bipolar resistive switching in ZnO/Pr0.7Ca0.3MnO3/ITO for invisible electronics application
2014
Abstract ZnO/Pr0.7Ca0.3MnO3 (ZnO/PCMO) amorphous thin films were grown on an indium-tin-oxide (ITO)/glass by pulsed laser deposition at room temperature. Interestingly, a stable bipolar resistive switching behavior of the ITO/ZnO/PCMO/ITO cell can be longer than 2.5 × 103 cycles. The on/off ratio of switching behaviors is as high as 104. The structure of ITO/ZnO/PCMO/ITO exhibits a high average transparency of 79.6% in the visible range with a maximum transparency of 84.6% at 590 nm wavelength. The conductive mechanism during switching cycling in our structure can be described by a trapped-control space charge limited current behavior. The ZnO/PCMO/ITO/glass structure shows a potential of t…
Radiation-induced defects in antiferroelectric thin films
2003
Abstract Radiation effects on highly oriented antiferroelectric (AFE) PbZrO3 (PZ) films with a thickness of approximately 400 nm are investigated in view of their possible application as a temperature sensitive element in a new bolometer system for fusion devices like ITER. The films were prepared by pulsed laser deposition (PLD). The dielectric constant was measured in the frequency range from 1 to 250 kHz in a stepwise cooling mode (∼2 °C min−1) from 400 °C to room temperature before and after irradiation to a fast neutron fluence of 2×1022 m−2 (E>0.1 MeV). After irradiation, the films were annealed in several steps up to ∼400 °C to remove the radiation-induced defects. The results are di…
Effects of the process conditions on the plume of a laser-irradiated indium–tin-oxide target
2001
Abstract The plume of a laser-ablated indium–tin-oxide target was investigated by optical emission spectroscopy. Atomic and ionic species of indium, tin and oxygen were observed; moreover, molecular bands of indium oxide were identified in the fluorescent spectra. The effects of the oxygen as a background gas and of the laser fluence on the behaviour of the ejected particles were studied with respect to the intensity of the emission and the delay time as a function of the observation distance from the target surface. The non-linear behaviour of the fluorescent species with the process conditions could infer spatial variations of the plume composition. The analysis demonstrates a plume expan…
Raman measurements on GaN thin films for PV - purposes
2012
Raman scattering (RS) is a very important experimental tool to characterize the optical modes and another elementary excitations of materials. Among other issues it can determine for example the degree of crystalline quality and point defects like local modes. Therefore GaN - thin films and related compounds for photovoltaic purposes and as processed by several systems have been measured by this technique. The films were grown by Molecular Beam Epitaxy (MBE), Close Spaced Vapor Transport (CSVT) and Laser Ablation (LA) with the use of optimal growth parameters and substrates. Gallium nitride crystallizes in the wurtzite structure with 4 atoms in the unit cell and presents 7 allowed Raman mod…