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PHOTOCHEMICAL DEPOSITION OF Pd-LOADED AND Pt-LOADED TIN OXIDE THIN FILMS
BUONO-CORE,G.E.; CABELLO,G.A.; ESPINOZA,H.; KLAHN,A.H.; TEJOS,M.; HILL,R.H.;
Journal of the Chilean Chemical Society , 2006, DOI: 10.4067/S0717-97072006000300004
Abstract: pd and pt loaded tin oxide thin films have been successfully prepared by direct uv irradiation of amorphous films of ?-diketonate complexes on si(100) substrates. tin oxide films loaded with 10, 30 and 50% pd and pt, were characterized by auger electron spectroscopy (aes). the auger peak intensity ratios of o kl23l23 to sn m4n45n45 showed that as-deposited films consist of mixed tin oxide phases whereas annealed films consist mainly of single phase sno2. the results showed that the stoichiometry of the resulting films is in relative agreement with the composition of the precursor films. the surface characterization of these thin films was performed using atomic force microscopy (afm). this analysis revealed that loaded tin oxide films have a much rougher surface than unloaded films, with rms roughness values ranging from 28-54 nm for as-deposited pd-snox films to 3.6-20 nm for as-deposited pt-snox films. it was also found that pt-loaded tin oxide films present a better particle size distribution and uniformity when compared to pd-loaded tin oxide films. these results demonstrate the potential use of these deposited films in the manufacture of gas-sensing devices
PHOTOCHEMICAL DEPOSITION OF Pd-LOADED AND Pt-LOADED TIN OXIDE THIN FILMS  [cached]
G.E. BUONO-CORE,G.A. CABELLO,H. ESPINOZA,A.H. KLAHN
Journal of the Chilean Chemical Society , 2006,
Abstract: Pd and Pt loaded tin OXide thin films have been successfully prepared by direct UV irradiation of amorphous films of -diketonate complexes on Si(100) substrates. Tin OXide films loaded with 10, 30 and 50% Pd and Pt, were characterized by Auger electron spectroscopy (AES). The Auger peak intensity ratios of O KL23L23 to Sn M4N45N45 showed that as-deposited films consist of mixed tin OXide phases whereas annealed films consist mainly of single phase SnO2. The results showed that the stoichiometry of the resulting films is in relative agreement with the composition of the precursor films. The surface characterization of these thin films was performed using Atomic Force Microscopy (AFM). This analysis revealed that loaded tin OXide films have a much rougher surface than unloaded films, with rms roughness values ranging from 28-54 nm for as-deposited Pd-SnO X films to 3.6-20 nm for as-deposited Pt-SnO X films. It was also found that Pt-loaded tin OXide films present a better particle size distribution and uniformity when compared to Pd-loaded tin OXide films. These results demonstrate the potential use of these deposited films in the manufacture of gas-sensing devices
Effects of argon ion irradiation on nucleation and growth of silver nanoparticles in a soda-glass matrix
P. Gangopadhyay,P. Magudapathy,S. K. Srivastava,K. G. M. Nair
AIP Advances , 2011, DOI: 10.1063/1.3623737
Abstract: The present article explores an experimental study for nucleation and non-equilibrium growth of silver nanoparticles in a soda-glass matrix. Ion-irradiation induced recoiling of silver atoms with argon ions (at energy 100 keV) facilitates nucleation as well as growth of the silver nanoparticles in the soda-glass matrix. Small growth of the silver nanoparticles in the soda-glass matrix has been experimentally observed after the irradiation with higher fluences of the argon ions. Role of the argon ions for the evolution of the silver nanoparticles in the soda-glass matrix has been elucidated in the present report. With increase of the argon-ion fluences, while slight athermal growth of the silver nanoparticles has been estimated, drastic increase in the optical responses and Rutherford backscattering (RBS) yields of the silver nanoparticles have been observed in the sample with the maximum fluences. Possible correlations of increase of argon-ion fluences and the observed experimental results (optical and RBS, in particular) have been explained in this article. Although it has been demonstrated using the silver metal film on a soda-glass substrate as a model example, the non-equilibrium approach of nucleation and ion-beam controlled growth of metal nanoparticles in a matrix should be applicable to other immiscible systems as well.
A Study of Surface Modification of Poly(lactic-co-glycolic) Acid Using Argon Ion Irradiation  [PDF]
Ananta Raj Adhikari, Buddhi Prasanga Tilakaratne, Dharshana Wijesundera, Wei-Kan Chu
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2014, DOI: 10.4236/jsemat.2014.46036
Abstract: The effect of Argon ion irradiation to the surface properties of poly(lactic-co-glycolic) acid (PLGA) was studied. A beam of 170 keV Argon ions was implanted at different fluencies (1 × 1012, 1 × 1013, 1 × 1014, and 1 × 1015 ions/cm2). X-ray photoelectron spectroscopy (XPS) was used to analyze the evolution of the bonding microstructure of PLGA due to irradiation. Surface morphology was monitored using atomic force microscopy (AFM). AFM analysis shows that film roughness increased to maximum at the dose of 1 × 1014 ions/cm2 where the formations of hillocks were also detected. Hydrophilicity of PLGA is important for their applications in biomedicine such as bioscaffolds. Hydrophilicity was monitored using water contact angle measurements for both unmodified and ion-modified PLGA. It was observed that hydrophilicity of PLGA changes with the ion irradiation. This demonstrates that ion irradiation can be an alternative approach to control hydrophilicity of PLGA. PLGA scaffolds modified with ion irradiation could therefore be more suitable for the biomedical applications.
Influence of oxygen flow rate on properties of indium tin oxide thin films prepared by ion-assisted electron beam evaporation
Artorn Pokaipisit,Mati Horprathum,Pichet Limsuwan
Songklanakarin Journal of Science and Technology , 2009,
Abstract: Indium tin oxide (ITO) thin films with various oxygen flow rates were deposited onto glass substrates by ion-assistedelectron beam evaporation. All other deposition parameters were kept constant. The electrical and optical properties of theITO thin films have been investigated as a function of oxygen flow rate. Optical transmittance and optical band gap energy were measured by spectrophotometer. Sheet resistance was measured by four-point probe method. It has been found that an oxygen flow rate at 12 sccm was suitable for improving the properties of ITO thin films. The resistivity and optical transmittance of ITO thin films were 7.2 10-4 -cm and 84%, respectively. The optical band gap was 4.19 eV.
Effect of 200 MeV Ag15+ ion irradiation on structural and electrical transport properties of Fe3O4 thin films  [PDF]
Ram Prakash,R. J. Choudhary,Shailja Tiwari,D. M. Phase,Ravi Kumar
Physics , 2009, DOI: 10.1016/j.nimb.2008.01.007
Abstract: Thin films of Fe3O4 have been deposited on single crystal MgO (100) and Si (100) substrates using pulsed laser deposition. Films grown on MgO substrate are epitaxial with c-axis orientation whereas, films on Si substrate are highly <111> oriented. Film thicknesses are 150 nm. These films have been irradiated with 200 MeV Ag ions. We study the effect of the irradiation on structural and electrical transport properties of these films. The fluence value of irradiation has been varied in the range of 5 x 1010 ions/cm2 to1 x 1012 ions/cm2. We compare the irradiation induced modifications on various physical properties between the c-axis oriented epitaxial film and non epitaxial but <111> oriented film. The pristine film on Si substrate shows Verwey transition (TV) close to 125 K, which is higher than generally observed in single crystals (121 K). After the irradiation with the 5 x 1010 ions/cm2 fluence value, TV shifts to 122 K, closer to the single crystal value. However, with the higher fluence (1 x 1012 ions/cm2) irradiation, TV again shifts to 125 K.
Study of multilayer coatings of Ti/TiN/TiC produced by pulsed arc discharge
Restrepo, E.;Benavides, V.;Devia, A.;Olarte, S.;Arroyave, M.;Arango, Y.C.;
Brazilian Journal of Physics , 2004, DOI: 10.1590/S0103-97332004000800043
Abstract: this work presents a study of multilayered ti/tin/tic thin films obtained using a papvd (plasma assisted physical vapor deposition) system by pulsed-arc discharge. for this purpose, a titanium target and a stainless steel substrate were used, placed on the cathode and on the anode, respectively, inside a vacuum chamber. to grow these films, different gases and concentrations were required. ti is obtained with argon gas, tin with nitrogen, and tic with methane, at 2.5 mbar and 5 mm distance between electrodes. by means of x ray diffraction (xrd), the phases present in the film were determined, observing (111), (200), and (100) orientations for both, tin and tic. also, by employing xrd techniques, titanium atoms distance (dta) was calculated at the interface of tin and tic, in order to study the crystallographic match. energy dispersive spectroscopy (eds) was employed in order to carry out elemental analyses in the materials. these analyses were obtained for 12 kev and 30 kev, observing the effects in the results. taking advantage of defects generated during the growth of the multilayer, chemical composition maps were carried out, probing the combination of ti and n in one layer and ti and c in the other layer. scanning electron microscopy (sem) technique allowed observing the presence of the multilayer, as well as the measurement of the thicknesses of each layer, which are in the order of nanometers.
Possibility to Use Low Temperature Pulsed RF Sputtered Indium Tin Oxide for the Fabrication of Organic Solar Cell  [PDF]
Somnath Middya,Animesh Layek,Partha Pratim Ray
Conference Papers in Science , 2013, DOI: 10.1155/2013/542726
Abstract: In this work we have used pulsed RF sputtering method to deposit indium tin oxide (ITO) for the fabrication of P3HT:PCBM based bulk heterojunction polymer solar cell. We have deposited ITO at low substrate temperature (100°C) and for different pulse modes. Oxygen was used as an admixture to the sputtering gas argon, and the percentage was varied from 0 to 6%. During deposition, plasma was studied by optical emission spectroscopy (OES) method. For our present range of deposition conditions lowest resistivity of ITO is around 2 × 10?4?Ω-cm, and it is deposited in High-Low mode with 1% of oxygen added to argon. The effect of oxygen admixture on electrical and optical properties of ITO thin films has been studied for different pulse modes. ITO films have been optimised by measuring their resistivity, transparency, and X-ray diffraction. Finally we have applied the ITO film for the fabrication of P3HT:PCBM based solar cell. 1. Introduction Many parameters of ITO thin film such as electrical conductivity, optical transparency, and depth of film to minimize sheet resistance must be considered in solar cell fabrication. The electrical and optical properties of this wide bandgap oxide semiconductor can be controlled by adjusting the deposition conditions. Various techniques, such as electron beam evaporation [1], ion beam assisted deposition [2], pulsed laser ablation [3], ion implantation [4], and DC/RF magnetron sputtering [5], are used for the growth of ITO thin films. Pulsed RF sputtering technique is a promising technique which can modify and improve the properties of sputtered films via control of energy of ions impinging on substrates. But pulsed RF sputtering is still not well tested for the deposition of thin ITO film at low temperature. In this work we have developed ITO by pulsed RF sputtering technique and applied that film for the fabrication of P3HT:PCBM based solar cell. We have also compared the cell performance with the cell deposited on commercially available ITO. 2. Experimental Thin film of ITO was deposited using a pulsed RF (13.56?MHz) sputtering system (ANELVA). An indium tin alloy (95:5) of 99.99% purity was used as target. Initially, the chamber was evacuated to 1 × 10?6 Torr (base pressure), and the required sputtering pressure inside the chamber was achieved by introducing argon gas through mass flow controller. Once the pressure was achieved, the deposition was carried out in argon and oxygen atmosphere. Oxygen was used as admixture to the sputtering gas, and the percentage was varied from 0 to 6%. The target was presputtered in argon
Pressure and Temperature Effects on Stoichiometry and Microstructure of Nitrogen-Rich TiN Thin Films Synthesized via Reactive Magnetron DC-Sputtering  [PDF]
E. Penilla,J. Wang
Journal of Nanomaterials , 2008, DOI: 10.1155/2008/267161
Abstract: Nitrogen-rich titanium nitride (TiN) thin films containing excess nitrogen up to 87.0 at.% were produced on (100) Si substrates via the reactive magnetron DC-sputtering of a commercially available 99.995 at.% pure Ti target within an argon-nitrogen (Ar-N2) atmosphere with a 20-to-1 gas ratio. The process pressure () and substrate temperature () at which deposition occurred were varied systematically between 0.26 Pa–1.60 Pa and between 15.0°C-600°C, respectively, and their effects on the chemical composition, surface morphology, and preferred orientation were characterized by energy dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM), and X-ray diffraction (XRD). The EDS analysis confirms increasing nitrogen content with increasing and . The SEM images reveal a uniform and crystallized surface morphology as well as a closely packed cross-sectional morphology for all crystalline films and a loosely packed cross-sectional morphology for amorphous films. Films produced at lower and have a pyramidal surface morphology which transitions to a columnar and stratified structure as and increase. The XRD analysis confirms the existence of only the -TiN phase and the absence of other nitrides, oxides, and/or sillicides in all cases. It also indicates that at lower and , the preferred orientation relative to the substrate is along the (111) planes, and that it transitions to a random orientation along the (200), (220), and (311) planes as and increase and these results correlate with and qualify those observed by SEM.
Swift Heavy Ion Irradiation-Induced Modifications in Structural, Optical, Electrical and Magnetic Properties of Mn Doped $SnO_{2-δ}$ Thin Films  [PDF]
Sushant Gupta,Fouran Singh,B. Das
Physics , 2015,
Abstract: Swift heavy ion irradiation is an effective technique to induce changes in the lattice of the materials leading to significant modification of properties. In this paper, we have presented the impact of swift heavy ion beam irradiation on the structural, optical, electrical and magnetic properties of $Sn_{0.9}Mn_{0.1}O_{2-\delta}$ thin films. Measurement of resistivity, mobility, carrier density, transmissivity to visible light, and saturation magnetization as a function of ion fluence ($1\times10^{11}$ to $3\times10^{13}$ $ions/cm^{2}$) promulgates that increasing fluence results in degradation in electrical, optical and magnetic properties of $Sn_{0.9}Mn_{0.1}O_{2-\delta}$. The structural, optical and electrical results have been interpreted by using properties of native or point defects, whereas the magnetic and morphological variations have been explained in terms of conductivity of material. Efforts have been made to summarize the properties of all possible charged and neutral point defects $(V_{Sn}^{4-}$, $Sn_{i}^{4+}$, $V_{O}^{0}$, $O_{i}^{2-}$, $Sn_{O}^{4+}$, $O_{Sn}^{2-}$, $H_{O}^{+})$ and afterwards from the correlation between experimentally-observed and theoretically-calculated results various interesting conclusions have been drawn.
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