Search results for " Pulsed laser deposition"

showing 7 items of 7 documents

Stability/Instability of Conductivity and Work Function Changes of ITO Thin Films, UV-Irradiated in Air or Vacuum. Measurements by the Four-Probe Met…

2001

This study shows that, after UV-irradiation in air or vacuum, conductivity and work function of ITO and In2O3 come back to their initial values in a few hours or minutes. In addition to this instability, one of the reported drawbacks of ITO is the indium diffusion into the organic layers of operating LED, leading to performance degradation. So, we have reconsidered ITO as transparent anode and explored alternatives such as NiO.

OLED Pulsed laser deposition Kelvin force microscopy Work function
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Enhancement of photoconversion efficiency in dye-sensitized solar cells exploiting pulsed laser deposited niobium pentoxide blocking layers

2015

Abstract Among all the photovoltaic technologies developed so far, dye-sensitized solar cells are considered as a promising alternative to the expensive and environmentally unfriendly crystalline silicon-based solar cells. One of the possible strategies employed to increase their photovoltaic efficiency is to reduce the charge recombination at the cell conductive substrate through the use of a compact blocking layer. In this paper, we report on the fabrication and characterization of dye-sensitized solar cells employing niobium pentoxide (Nb 2 O 5 ) thin film blocking layer deposited through the pulsed laser deposition technique on conductive substrates. The careful selection of the optimal…

Materials scienceOpen circuit voltage decaySubstrate (electronics)Dye-sensitized solar cellsSettore ING-INF/01 - ElettronicaPulsed laser depositionBlocking layer; Dye-sensitized solar cells; Electrochemical impedance spectroscopy; Niobium pentoxide; Open circuit voltage decay; Pulsed laser deposition; Electronic Optical and Magnetic Materials; Materials Chemistry; 2506; Metals and Alloys; 2506; Surfaces Coatings and Films; Surfaces and InterfacesCoatings and Filmschemistry.chemical_compoundElectronicMaterials ChemistryOptical and Magnetic MaterialsCrystalline siliconThin filmNiobium pentoxidepulsed laser depositionbusiness.industryOpen-circuit voltagePhotovoltaic systemMetals and AlloysSurfaces and InterfacesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsSurfacesDye-sensitized Solar CellDye-sensitized solar cellniobium pentoxidechemistryblocking layerOptoelectronics2506businessElectrochemical impedance spectroscopyThin Solid Films
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Electrochemical methods for carrier type identification of ZnO films grown by pulsed laser deposition on InP.

2013

Electrochemical methods carrier type identification ZnO films pulsed laser deposition InP.Settore ING-IND/23 - Chimica Fisica ApplicataSettore ING-INF/01 - Elettronica
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Analysis of Transition Metal Oxides based Heterojunction Solar Cells with S-shaped J-V curves

2020

The use of transition metal oxides for the selective carrier contact in the crystalline silicon solar cells technology is rising to interest for the excellent optoelectrical properties of these materials whose implementation, however, can result in lousy performing cells due to an S-shaped electrical characteristic. In this paper, we fabricated solar cells showing S-shaped J-V curve and carried out an analysis of the reasons of such behavior using a model involving the series of a standard cell equivalent circuit with a Schottky junction in order to explain these atypical performances. A good matching between the experimental measurements and the adopted theoretical model was obtained. The …

Standard cellMaterials scienceheterojunctionbusiness.industry020209 energySchottky barrier020208 electrical & electronic engineeringHeterojunction02 engineering and technologySettore ING-INF/01 - ElettronicaPulsed laser depositions-shapeTransition metalSolar cells heterojunction transition metal oxides pulsed laser deposition s-shapesolar cells0202 electrical engineering electronic engineering information engineeringEquivalent circuitOptoelectronicsCrystalline silicontransition metal oxidesbusinesspulsed laser deposition
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Effect of the Si doping on the properties of AZO/SiC/Si heterojunctions grown by low temperature pulsed laser deposition

2020

Abstract The structural and photoelectrical properties of Al-doped ZnO (AZO)/SiC/p-Si and AZO/SiC/n-Si heterojunctions, fabricated at low temperature by pulsed laser deposition, were investigated by means of a number of techniques. Raman analysis indicates that SiC layers have the cubic 3C-SiC phase, whilst X-ray diffraction measurements show that AZO films exhibit a hexagonal wurtzite structure, highly textured along the c-axis, with average crystallites size of 35.1 nm and lattice parameter c of 0.518 nm. The homogeneous and dense surface morphology observed by scanning electron microscopy was confirmed by atomic force microscopy images. Moreover, UV–Vis-NIR spectra indicated a high trans…

silicon carbide zinc oxide AZO heterojunction pulsed laser depositionMaterials sciencebusiness.industryDopingHeterojunctionCondensed Matter PhysicsSettore ING-INF/01 - ElettronicaElectronic Optical and Magnetic MaterialsPulsed laser depositionSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialiMaterials ChemistryOptoelectronicsElectrical and Electronic EngineeringbusinessSemiconductor Science and Technology
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Density of States characterization of TiO2 films deposited by Pulsed Laser Deposition for Heterojunction solar cells

2021

The application of titanium dioxide (TiO2) in the photovoltaic field is gaining traction as this material can be deployed in doping-free heterojunction solar cells with the role of electron selective contact. For modeling-based optimization of such contact, knowledge of the titanium oxide defect density of states is crucial. In this paper, we report a method to extract the defect density through nondestructive optical measures, including the contribution given by small polaron optical transitions. The presence of both related to oxygen-vacancy defects and polarons is supported by the results of optical characterizations and the evaluation of previous observations resulting in a defect band …

Solar cell heterojunction photovoltaic defect density small polaron Pulsed Laser Deposition titanium dioxide defectsGeneral Materials ScienceElectrical and Electronic EngineeringCondensed Matter PhysicsSettore ING-INF/01 - ElettronicaAtomic and Molecular Physics and Optics
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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…

Materials sciencebusiness.industryAnalytical chemistryPlasmaIndium–tin-oxide films Pulsed laser deposition Optical emission spectroscopy Plasma diagnosticsSettore ING-INF/01 - ElettronicaAtomic and Molecular Physics and OpticsAnalytical ChemistryIndium tin oxidePulsed laser depositionElectrical resistivity and conductivityOptoelectronicsPlasma diagnosticsPLD ITO optical spectroscopyThin filmbusinessInstrumentationSpectroscopyDeposition (law)Line (formation)Spectrochimica Acta Part B: Atomic Spectroscopy
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