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This paper describes a simple and low-temperature approach to fabrication of dense and crack-free gadolinium doped ceria (GDC) thin films with controllable deposition by a magnetic-field-assisted electrostatic spray deposition technique. The influences of external permanent magnets on the deposition of GDC films were investigated. The coating area deposited using two magnets with the same pole arrangement decreased in comparison with the case of no magnets, whereas the largest deposition area was obtained in the system of the opposite poles. Analysis of as-deposited films at 450°C indicated the formation of uniform, smooth and dense thin films with a single-phase fluorite structure. The films produced in the system using same poles were thicker, smaller in crystallite size and smoother than those fabricated under other conditions. Additionally, the GDC film deposited using the same pole arrangement showed the maximum in electrical conductivity of about 2.5×10−2 S/cm at a low operating temperature of 500°C. [ABSTRACT FROM AUTHOR]

Abstract: Indium tin oxide coatings were deposited by magnetron sputtering physical vapour deposition under different atmospheres. Microstructural, electrical, and optical properties were measured, finding a correlation among properties and process parameters. Texture analyses carried out by X-ray diffraction showed that films microstructure depended by the oxygen content in the deposition vessel: high values of the oxygen content (e.g., 5%) caused the film to grow along the <111> orientation; under pure Ar, the grains grew along the <100> orientation. Intermediate values of the oxygen content caused the growth of two families of grains, respectively oriented along the <111> and the <100> directions. [Copyright &y& Elsevier]

Abstract: We investigated the optimal deposition conditions of a thin indium tin oxide (ITO) film on an amorphous silicon (a-Si) single-junction solar cell using pulsed DC magnetron sputtering. Thin ITO films were deposited while power, deposition time, pressure, gas flow and temperature were varied to find such conditions. The efficiency of a-Si solar cells with ITO films was 6.65% at the optimal conditions — a pulsed DC power of 40W, a deposition time of 460s, a pressure of 0.53Pa, gas flow of 16sccm and 151°C. On the other hand, an a-SiGe tandem solar cell with the ITO films made at the optimal conditions yields an efficiency of 7.20%. We have also examined the surface morphology of ITO coated a-Si solar cells, using atomic force microscopy. Interestingly, a change in power does not alter the surface morphology at small length scales, whereas at large scales, the lower power sample had a lower surface roughness than the samples made with higher powers. We also find that for the range of deposition conditions examined, the value of the roughness exponent does not change with α ≃2/3 and a thin layer of ITO does not modify the surface morphology significantly. [Copyright &y& Elsevier]

Abstract: This paper describes the growth mechanism and structure of Si whiskers grown on a Si substrate in a tungsten hot filament chemical vapor deposition reactor with pure hydrogen as source gas using a two step process. In the first step, atomic hydrogen etched the silicon surface, forming silicon hydrides that react with tungsten from the filament. The resulting silicide particles deposited on the silicon surface forming a mesh-like pattern. The particles work as an etching mask against hydrogen radical etching of the silicon surface and inverted-pyramids or V-groove-shaped surface texture were obtained. In the second step the filament current was reduced and whiskers grew onto the substrate due to the interaction of the silicon hydrides with the particles and subsequent precipitation of saturated Si. The whiskers were found to have tungsten silicide particles on their tip, suggesting the whisker growth was through the Vapor–Solid–Solid (VSS) mechanism. A balance between the hydrogen radical etching effect and the supply of silicon hydride from the etching reaction on the silicon surface is crucial for the growth of dense silicon whiskers. [Copyright &y& Elsevier]

Abstract: Experimental and modeling studies of the gas-phase chemistry occurring in dilute, hot filament (HF) activated B2H6/CH4/H2 gas mixtures appropriate for growth of boron-doped diamond are reported. The results of two-dimensional modeling of heat and mass transfer processes and the B/H/C chemistry prevailing in such HF activated gas mixtures (supplemented by reactions involving trace O2 present as air impurity in the process gas mixture) are discussed and compared with measurements of B atom densities as functions of the hot wire temperature T w and distance from the wire. Most of the B2H6 molecules that diffuse from the cool, near-wall regions into the hot, near wire region are thermally decomposed (yielding two BH3 molecules as primary products) and then converted into various ‘active’ B-containing species like B, BH and BH2 — some of which are able to accommodate into the growing diamond film. H-shifting reactions BH x +H↔BH x −1 +H2 enable rapid inter-conversion between the various BH x (x =0–3) species and the BH x source is limited by diffusional transfer of B2H6. H atoms play several key roles — e.g. activating the process gas mixture, and driving inter-conversions between the various H x B y C z O z′ species. We show that the T w and gas pressure dependences of the H atom production rate (by H2 dissociation on the HF surface) can be accommodated by a simple gas-surface reaction model. [Copyright &y& Elsevier]

Abstract: A cost-effective and promising simple deposition method, electrostatic spray deposition (ESD), was used to fabricate dense scandium stabilized zirconia (ScSZ) thin films. The effect of solvent mixtures on their surface morphology was investigated. The films deposited using a mixed ethanol-butyl carbitol solvent with high boiling point showed higher smoothness compared with those deposited using ethanol and a mixture of ethanol and ethylene glycol, respectively. Single-phase ScSZ dense films were formed within 2h at a low deposition temperature of 450°C. Analysis of as heat-treated films using scanning electron microscope and atomic force microscope also indicated the formation of the uniform, smooth and dense thin films even at a low densification temperature. Furthermore, the ScSZ film deposited under the optimal condition showed the maximum in electrical conductivity of approximately 0.33Scm−1 at a low operating temperature of 800°C. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with a simple and low-cost method developed to deposit hematite (α-Fe2O3) layers on a fluorine-doped tin oxide (FTO/F:SnO2) substrate by thermal decomposition of solid iron(III) chloride hexahydrate (FeCl3⋅6H2O). Deposition procedure takes place through chemical intermediate iron(III) oxide chloride (FeOCl) film. A crucial influence of atmosphere dynamics involved in the calcination process of FeOCl has been observed. As-deposited films were characterized by means of Conversion Electron Mössbauer Spectroscopy (CEMS), Grazing Angle X-Ray Diffractometry (GAXRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) analysis. Final nanocrystalline hematite film with a cactus-field-like design consists of 20nm thick porous crystal plates. A process of hematite doping by tin atoms from substrate coating is also discussed. [Copyright &y& Elsevier]

Abstract: The initial stages of HfO2 film growth by atomic layer deposition (ALD) on Co, Ta, and Pt thin films have been compared by x-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared spectroscopy. The initial tetrakis-dimethylamido(IV) hafnium (TDMAH) adsorption rate was highest on Co and increased with substrate temperature between 150°C and 250°C. The initial adsorption rate of TDMAH on Ta was less than on Co or Pt at the same substrate temperatures. The Ta surface also proved to be more stable with regard to TDMAH decomposition as fluctuations of adsorbed Hf and decomposition products were not observed during ALD cycling. Larger amounts of carbon were observed on Pt after TDMAH exposure compared to Co or Ta, suggestive of decomposition products. The XPS Hf(4f) peak measured after initial exposure of TDMAH on Pt showed evidence of two Hf oxidation states at the surface. It is postulated that the reaction of TDMAH and decomposition by-products with available oxygen or hydroxyl molecules at the surface of the various metal underlayers affected the initial growth of HfO2. [Copyright &y& Elsevier]

Abstract: The procedures of Pd-noble metal alloy (Pd-Au, Pd-Pt, Pd-Rh, Pd-Pt-Rh) preparation by electrochemical deposition from chloride solutions are described. The influence of deposition conditions on alloy composition is presented. The deposits were characterized electrochemically in acidic solutions (H2SO4 aq) by cyclic voltammetry. The surface morphology of the alloys was examined by scanning electron microscopy and scanning tunneling microscopy. The alloy surface composition was investigated in situ by the electrochemical method and ex situ by Auger electron spectroscopy, while the bulk composition was determined by energy dispersive analysis of X-rays and atomic absorption spectroscopy. The electrochemical methods of the real surface area determination were compared and discussed. [Copyright &y& Elsevier]

Abstract: Ge0.7Mn0.3 thin films were fabricated on Al2O3 (0001) and glass substrates at growth temperatures ranging from room temperature to 500 °C by a radio frequency magnetron sputtering. We found that the Ge0.7Mn0.3 thin films showed a polycrystalline-to-amorphous transition at about 360 °C, and the ferromagnetic transition temperature of each thin film depends on its structure — crystalline or amorphous states. Particularly, the Ge0.7Mn0.3 thin films showed room temperature ferromagnetism when they were fabricated at temperatures above the crystallization temperature. [Copyright &y& Elsevier]

Abstract: Cu/TiO2 composite films were prepared at low temperature on glass substrates by a photodeposition method. Films were deposited by irradiating the substrate while in contact with an aqueous TiO2 suspension containing copper(II) nitrate and ethanol. Cu/TiO2 composite films of 500 nm in thickness were deposited at room temperature after a short irradiation time (15 min) with a 125 W mercury vapour lamp. According to scanning electron microscopy observations, the obtained films were homogeneous and porous. Energy dispersive X-ray spectroscopy analysis revealed a 3:1 Cu:Ti atomic ratio. Grazing angle X-ray diffraction analysis showed that the films contained Cu and TiO2 as major components and Cu2O as a minor component. Heat treatment at 400 °C in air for a period of 3 h transformed the initial material into a CuO/TiO2 composite, improved the adhesion to the substrate and favoured a more regular distribution of copper oxide according to backscattering micrographs. [Copyright &y& Elsevier]

Abstract: This paper describes an increase in thickness of spin coated layers by using IR-irradiation. Hybrid suspensions with 5 wt.% solid content (80% BaTiO3, 20% ZrO2) are spin coated on platinized silicon wafers. The IR-irradiation increases the evaporation rate and accelerates the aging of the solution. This leads to an increase in viscosity and a faster increase of the solid content, which results in an earlier percolation of the hybrid suspension with more particles remaining on the substrate. Using IR-irradiation, an increase in layer thickness from 71 nm to 242 nm could be achieved in one coating step. [Copyright &y& Elsevier]

Abstract: Metal oxide semiconductor (MOS) capacitors with titanium oxide (TiO x ) dielectric layer, deposited with different oxygen partial pressure (30, 35 and 40%) and annealed at 550, 750 and 1000 °C, were fabricated and characterized. Capacitance–voltage and current–voltage measurements were utilized to obtain, the effective dielectric constant, effective oxide thickness, leakage current density and interface quality. The obtained TiO x films present a dielectric constant varying from 40 to 170 and a leakage current density, for a gate voltage of −1 V, as low as 1 nA/cm2 for some of the structures, acceptable for MOS fabrication, indicating that this material is a viable high dielectric constant substitute for current ultra thin dielectric layers. [Copyright &y& Elsevier]

Abstract: The electrophoretic deposition of cadmium selenide (CdSe) nanocrystal films from a stable hexane suspension onto a dielectric polymer film is reported. The electrodes were prepared by spin casting a ~30 nm thick smooth, defect-free, polystyrene film on silicon substrates. Scanning electron microscopy and atomic force microscopy showed that the CdSe films deposited atop polystyrene possessed morphology comparable to CdSe films deposited on the bare silicon electrodes. Factors affecting deposition, such as nanocrystal charging in suspension and wetting of electrode surfaces, are reviewed. This approach to preparing nanocrystal films onto homogeneous dielectric layers will facilitate the fabrication of novel polymer-nanocrystal composites. [Copyright &y& Elsevier]

Abstract: In this paper the deposition of thin films obtained from femtosecond laser ablation of an Al70Cu20Fe10 alloy is presented. In the plasma produced by ablation, a characteristic feature is the presence of hot nanoparticles that become evident several microseconds after the laser shot. The cooling mechanisms of these particles have been analysed together with the evolution of their composition. The results, compared with those previously obtained for Al65Cu23Fe12 quasicrystal, reveal a clear relation between the final composition of the particles and the high-temperature equilibrium vapor pressures of the different elements, suggesting a direct emission from the target rather than a gas phase formation. Analysis of the elemental composition through the cross-section of the as-deposited films helps to illustrate the role of nanoparticles in the film growth. [Copyright &y& Elsevier]

Abstract: In the present study a Pd–Ni–P film has been fabricated by electroless alloy plating. The fabricated Pd–Ni–P film was found to be a metallic glass on the basis of two features, namely, an amorphous structure and a glass transition followed by crystallization during heating. The thermal stability of the supercooled liquid region, however, was lower than that of bulk Pd–Ni–P metallic glass. And unlike the conventional metallic glasses, the fabricated Pd–Ni–P film did not have a uniform microstructure. The non-uniform microstructure of this film resulted from the inhomogeneous distribution of the free volume accompanying the electroless alloy plating reaction. [Copyright &y& Elsevier]

Abstract: NiO–Ce0.8Gd0.2O1.9− x (CGO) thin films were prepared by air blast spray pyrolysis with precursors containing nickel nitrate, cerium nitrate and gadolinium chloride in ethanol and a high boiling point organic solvent. Precursors containing solvents with boiling points between 120 and 314 °C were sprayed on sapphire, silicon, Foturan®, yttria stabilized zirconia and CGO at different substrate surface temperatures. A maximum deposition temperature, above which film deposition ceased completely, was observed. The limiting temperature for film formation was correlated with the Leidenfrost phenomenon. At temperatures above the Leidenfrost point of the precursor, the sprayed droplets do not impact and spread on the substrate surface but levitate on a vapour cushion above the substrate and are swept away by the air stream. The Leidenfrost point of a precursor was found to depend on the solvent boiling point, the metal salt concentration and the thermal properties of the substrate expressed as the product of density, thermal conductivity and heat capacity. The maximum deposition temperature increased with increasing solvent boiling point or metal salt concentration and with decreasing product of density, thermal conductivity and heat capacity of the substrate. [Copyright &y& Elsevier]

Abstract: The formation of nickel oxide (NiO), cerium gadolinium oxide (CGO) and NiO–CGO thin films by air blast spray pyrolysis was studied at two scales. First, single droplets of precursor were deposited on sapphire substrates and the morphology of the formed residue was studied as a function of the substrate surface temperature, type of metal salt, salt saturation, and organic solvent in the precursor. Second, the synthesis of continuous films from repetitively deposited droplets and crack formation in the films were studied as a function of substrate temperature and salt decomposition kinetics. Nitrates, acetates, perchlorates and chlorides of nickel, cerium and gadolinium were the metal salts used, and mixtures of ethanol or water with di-, tri- and tetraethylene glycol were used as solvents. Regular ring- or disc-shaped deposits were formed from single droplets that evaporated without boiling and were mainly observed with metal acetate- and chloride-based spray solutions or at low substrate temperatures. Disc-shaped residues were obtained for saturated salt solutions and changed to rings with diminishing rim thickness with decreasing salt saturation. The formation of bubbles in the droplet from boiling or salt decomposition during evaporation resulted in the distortion of the circular shape and was predominantly observed for metal nitrate-based precursors and at high substrate surface temperatures. Continuous, dense and crack-free films of CGO and NiO–CGO with thicknesses up to 500 and 800 nm, respectively, were prepared from metal nitrate/chloride mixtures in a tetraethylene glycol-based solvent. The maximum crack-free thickness decreased with decreasing deposition temperature and was correlated to the metal salt decomposition kinetics. [Copyright &y& Elsevier]

Abstract: Low pressure chemical vapor deposition has been used to fill carbon nanotube (CNT) forests with inorganic materials (polysilicon and silicon nitride). Forest filling proceeds by deposition around individual CNTs. As the coating thickness around each CNT increases, the free volume between adjacent nanotubes is filled and finally results in a contiguous composite film. The process maintains the forest height and alignment; however, the coating thickness around the CNTs is in general smaller at the base of the forest than it is at the top. This can cause a contiguous solid film to form at the top of the forest while the forest is only partially filled at the base. Once the top of the forest becomes filled, it prevents growth from occurring at the base. Consequently, the growth process can cap the top of the forest and leave voids between thinly coated CNTs at the base. Such composites have reduced hardness (4 GPa or less). Depositing at reduced temperatures and/or decreased precursor gas flow rates reduces the void fraction through improving the step coverage modulus. This allows one to produce thick (>50 μm) polysilicon-CNT composite films having hardness approximately equal to that of polysilicon thin films (12.4 GPa). [Copyright &y& Elsevier]

Abstract: The effect of the deposition type on the resulting overall structure of multilayer Langmuir–Blodgett (LB) films of terthiophene-vinylbenzoate (TSe) embedded in an octadecyl amine (ODA) matrix was studied. In UV–Vis polarized absorption spectra a large hypsochromic shift is observed for the LB-films compared with the solution indicating that TSe exists predominantly as aggregates in the films. In second harmonic generation (SHG) measurements the signal from the Y-type film was very weak as would be expected for an essentially centrosymmetric system. For X- and Z-type films, similar SHG signals were expected since the orientation of the active molecules should be uniform although opposite in these films. However, the SHG signal from the Z-type films was spatially inhomogeneous and much lower than that from the X-type film. The reason for these differences lies in the details of the film deposition process. In the preparation of Z-type films, the long time exposure of the hydrophobic part of the film to the aqueous subphase induces turning over of the molecules. Thus, the monolayer structure achieved at the air-subphase interface breaks down resulting in only partly organized films with decreased SHG intensity. For X-type films no such exposure takes place during the deposition and all TSe molecules remain in the original orientation. [Copyright &y& Elsevier]

Abstract: Low- and atmospheric-pressure plasma co-polymerisations of binary gas mixtures of C2H4 and NH3 or N2, respectively, were investigated for depositing N-rich plasma polymer coatings for biomedical applications. Deposition kinetics and relevant surface characteristics of resulting plasma polymerised ethylene enriched with nitrogen, “PPE:N”, coatings were investigated as a function of the gas mixture ratio, X =NH3(N2)/C2H4. Physico-chemical properties of the coatings were determined using a combination of complementary surface-sensitive techniques: for example, total nitrogen concentrations, [N], up to 40 at.% were measured by X-ray Photoelectron Spectroscopy, XPS, while those of primary amines, [–NH2], were determined by performing chemical derivatisation followed by XPS analyses. PPE:N films were further characterised by UV–VIS Ellipsometry, Near Edge X-ray Absorption Fine Structure Spectroscopy, IR Spectroscopy and by Contact Angle Goniometry measurements. The stability of the coatings was tested, both in terms of water solubility and of “ageing” in ambient atmosphere. For the latter, selected samples were stored in the laboratory for different durations, in order to assess possible changes in their chemical structures. [Copyright &y& Elsevier]

Abstract: A synthetic avenue for the formation of yttrium oxide thin films on Si native oxide surfaces is demonstrated by the reaction of Tris(2,2,6,6-tetramethyl-3,5-heptanedionato) yttrium(III) with inorganic (H2O2) and organic (tert-butyl and di-tert-amyl) peroxides in supercritical carbon dioxide. The reactions are carried out in a hot wall reactor at temperatures below 130 °C and pressures ranging from 13.10 to 22.75 MPa. Spectroscopic Ellipsometry verifies thin film formation and X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy measurements confirm formation of yttrium oxide films and the presence of carbonate and hydroxide species which are removed after high temperature anneals. [Copyright &y& Elsevier]

Abstract: Silicon thin films were grown by plasma enhanced chemical vapor deposition at high-pressure (700 Pa), high-power (4– W/cm2) depletion regime using multi-hole cathode. Series of samples were deposited by varying hydrogen/silane ratio or plasma power to study evolution of film structure and transport properties near a-Si:H/μc-Si:H transition. We suggest a simple “μc-Si:H layer quality factor” based on the ratio of subgap optical absorption α (1.4 eV)/α (1 eV) measured by constant photocurrent method. This ratio correlates well with the values of ambipolar diffusion lengths measured by surface photovoltage method perpendicularly to the substrate, i.e., in the direction of the collection of the photogenerated carriers in solar cells. [Copyright &y& Elsevier]

Abstract: MgH x thin films are grown by activated reactive evaporation in a Molecular Beam Epitaxy system fitted with an atomic hydrogen source. During deposition the electrical and optical properties are measured in-situ. The structural properties are determined ex-situ by Atomic Force Microscopy. These measurements confirm the growth of the MgH2 phase, however the presence of 10 vol.% of metallic Mg cannot be prevented. The metallic Mg grains cause an optical absorption edge at 2.0 eV, which has a completely different origin than the observed band gap of MgH2 at 5.6 eV. The observed optical spectra can be modelled using an effective medium theory. The Mg hydride films are electrically insulating despite the presence of metallic Mg particles. Upon re-hydrogenation of a de-hydrogenated in-situ grown MgH x thin film, the absorption edge at 2.0 eV disappears and the resistivity decreases to values normally observed for ex-situ hydrogenated films. [Copyright &y& Elsevier]

Abstract: Electrochemical polymerisation of luminol (Lum) with aniline (Ani) is carried out potentiodynamically from acidic medium with different monomers concentration ratios. Aniline units incorporation in the polymer structure is observable in the current density/potential profiles of the polymerisation and characterisation, in acidic medium, by the development of two polyaniline (PAni) like redox switching processes with increasing aniline concentration. Poly(Luminol–Aniline) (P(Lum–Ani)) films characterised in acidic medium show electroactive and stable behaviour, in which the redox process ascribed as polyluminol (PLum) type is overlaid with that of PAni displaying pH sensitivity. Unlike PAni films, the P(Lum–Ani) polymer is electroactive and stable in basic medium and a single redox switching process is observed; its redox charge is enhanced with the increase of aniline concentration in the polymerisation solution. [Copyright &y& Elsevier]

Abstract: An atmospheric pressure aerosol assisted deposition method has been developed to grow highly oriented nanoparticles and thin continuous films of platinum on a variety of substrates for applications such as catalysts including their use in proton exchange membrane fuel cells. Pt nanoparticles with sizes ranging from 4 nm to 78 nm were synthesized on Si, silicon dioxide coated Si substrates and carbon nanotubes. The size and density of the nanoparticles was found to depend strongly on the precursor carrier gas flow rate and deposition time. The particles showed preferential orientation of (111) that was independent of substrate used. The resulting nanoparticles were characterized by Scanning Electron Microscopy, X-ray Diffraction Spectroscopy and X-ray Photoelectron Spectroscopy in order to obtain information about their morphology, crystallinity and composition. The method developed can deposit uniform coatings of highly oriented, pure Pt nanoparticles without the need of any substrate pretreatment such as surface functionalization, deposition of seed layer for electrodeposition on insulating or semiconducting substrates, and without the use of expensive vacuum equipment. [Copyright &y& Elsevier]

Abstract: This paper presents experimental evidence that thin (<∼200 nm) boron coatings, deposited with a (vacuum) cathodic arc technique on pre-polished Co–Cr–Mo surfaces, could potentially extend the life of metal-on-polymer orthopedic devices using cast Co–Cr–Mo alloy for the metal component. The primary tribological test used a linear, reciprocating pin-on-disc arrangement, with pins made of ultra-high molecular weight polyethylene. The disks were cast Co–Cr–Mo samples that were metallographically polished and then coated with boron at a substrate bias of 500 V and at about 100 °C. The wear tests were carried out in a saline solution to simulate the biological environment. The improvements were manifested by the absence of a detectable wear track scar on the coated metal component, while significant polymer transfer film was detected on the uncoated (control) samples tested under the same conditions. The polymer transfer track was characterized with both profilometry and Rutherford backscattering spectroscopy. Mechanical characterization of the thin films included nano-indentation, as well as additional pin-on-disk tests with a steel ball to demonstrate adhesion, using ultra-high frequency acoustic microscopy to probe for any void occurrence at the coating–substrate interface. [Copyright &y& Elsevier]

Abstract: ZnO nanoparticles were prepared and self-assembled hybrid nanolayers were generated on the surface of silicon wafers using the layer silicate hectorite and PSS (sodium polystyrene-sulfonate) polyelectrolyte. The thickness, light absorption and interference properties of the hybrid films were studied. The influence of layer silicates and polymers on the self-organizing properties of ZnO nanoparticles was examined. Utilization of the nanofilms as optical sensors was investigated: they can adsorb ethanol vapor and their reflection and light interference properties are thereby significantly altered. [Copyright &y& Elsevier]

Abstract: Ni thin films were electrodeposited on n-Si (100) substrate from the electrolytes containing Ni(CH3COO)2 and CH3COONH4 at room temperature. The scanning electron microscope images of the films reveals the uniform distribution of the nickel all over the substrate surface, which illustrates that the fine Ni films on large scales could be obtained through the method of electrodeposition. Vibrating sample magnetometer measurement with the applied field parallel to the surface shows obvious hysteresis loops of the magnetic thin films. The morphology and magnetism of the Ni thin films evolves with the deposition time increasing. The effect of deposition conditions on the properties of the Ni thin films is investigated. [Copyright &y& Elsevier]

Abstract: We report the fabrication of polymer thin films with “in-depth” dye-dispersed structures using a vacuum spray method. Copper (II) 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine [(t-Bu)4CuPc] and polycarbonate in chloroform solution were sprayed onto the substrate. The (t-Bu)4CuPc distribution was controlled precisely during thin film growth by varying its concentration in the solution. Uniform, bilayer, and gradient structures of (t-Bu)4CuPc dispersed in thin films were confirmed by high-angle annular dark field imaging on scanning transmission electron microscopy. The vacuum spray method has several advantages compared to the casting method, such as smaller dispersed dye-aggregates and lack of cavities due to air bubbles. [Copyright &y& Elsevier]

Abstract: M and M–N coatings, where M is nearly the metal composition of Inconel 690 (57 at.% Ni, 32 at.% Cr, 9.5 at.% Fe…) were sputter-deposited on glass and steel substrates in pure argon and in Ar–N2 mixtures using a round planar magnetron. The influence of nitrogen gas flow rate inlet in argon on chemical composition and microstructure was studied. The as-deposited (T <100 °C) M–N films containing up to 30 at.% nitrogen are a nanocrystalline supersaturated face cubic centered (fcc) solid solution (γ N). The pure metallic films have a pronounced<111>fcc crystallographic texture, while the M–N films exhibit a strong<100>fcc crystallographic texture. The effect of temperature on the microstructure of M–N films was studied by increasing the substrate temperature during preparation and by tempering of an as-deposited M–N films. For M–N films prepared at 400 °C, the X-ray diffraction analysis reveals a magnetic γ phase with a very low nitrogen content, while electron probe microanalysis gives an overall high nitrogen content in the layer (up to 25 at.%). It is concluded that the layers consist of two phases when prepared or tempered at high temperature (T >400 °C): an fcc CrN nitride and a γ (Ni,Fe,Cr) depleted in nitrogen. [Copyright &y& Elsevier]

Abstract: Hot-wire chemical vapor deposition (HWCVD) and plasma-enhanced chemical vapor deposition (PECVD) of Si thin films show different growth kinetic processes. According to the fractal analysis, the root-mean-square surface roughness δ and the film thickness d have the relation of δ ∼ d β , where β is the dynamic scaling exponent related to the film growth mechanism. It was found that β is 0.44 for Si films prepared by HWCVD and 0.24 by PECVD. The former refers to a stochastic deposition while the latter corresponds to the finite diffusion of the radicals. Monte Carlo simulations indicate that the sticking process of growth radicals play an important role in determining the morphology of Si films. [Copyright &y& Elsevier]

Abstract: This paper describes at first the present status of solar cell efficiencies prepared by Hot Wire CVD (HW-CVD), and then preparation techniques of μc-3C(cubic)-SiC developed for innovative solar cell applications by using HW-CVD method are presented. For preparing μc-3C-SiC, monomethylsilane (MMS) and hydrogen were used for reactant gases. The high conductivity of 5 S/cm could be achieved for N doped n-type μc-3C-SiC. For p-type, as-grown Al-doped μc-3C-SiC films showed a relatively high resistivity, but on thermal annealing, the conductivity increased to the level of 1×10−2 S/cm. Monomethylgermane (MMG) and H2 were used to prepare μc-GeC thin films. μc-GeC thin films with a carbon composition of about 7–8% showed a clear shift of absorption coefficient spectra by 0.44 eV, when compared to crystalline Ge. The pin solar cell structures in which all p,i,n layers consist of μc-SiC have been prepared for the first time. It was found that μc-3C-SiC and μc-GeC are the promising candidates as the next generation thin-film solar cell materials, but at present, the film quality is strictly limited by the residual impurity concentration of filament material Re. [Copyright &y& Elsevier]

Abstract: Hafnium oxide thin films with a reactive dual-magnetron sputtering system were studied. They can be used for multilayer dielectric mirrors at wavelengths of 250 nm and longer. The regimes (and modes) at different electric powers and gas flows were studied and operational points were found. The power and oxygen-control (lambda-control) techniques were applied to optimize the optical quality of the hafnium oxide film. The dispersion curves of the refractive index and extinction coefficient for different regimes were obtained. The reflectivity and transmission of HfO2/SiO2 stacks are demonstrated, with losses of <0.1% at the wavelength of 800 nm. [Copyright &y& Elsevier]

Abstract: Plasma polymerization processes are widely used to chemically functionalize surfaces, which properties can be tuned by different operating variables. In this study, thin amine-containing polymer layers were produced on solid substrates in a custom-made cylindrical plasma polymerization reactor by radio frequency glow discharges of n-heptylamine vapours. Carefully planned experiments were conducted to evaluate the importance of four different process parameters on the chemical composition and thickness of the resulting films. The parameters investigated were: 1) deposition time, 2) power of the glow discharge, 3) distance between the electrodes, and 4) monomer pressure. Possible interactions between these variables were investigated through the use of statistical analyses (i.e., factorial design). This study reveals that n-heptylamine plasma polymer (HApp) layer thickness is influenced by the power of the glow discharge and the deposition time, as assessed by surface plasmon resonance and atomic force microscopy step height measurements. Also, the atomic ratio of nitrogen to carbon atoms on the treated surfaces is mainly influenced by the power of the glow discharge, as revealed by X-ray photoelectron spectroscopy. Quartz crystal microbalance analysis also confirmed that HApp layers are stable when immersed in aqueous solution. [Copyright &y& Elsevier]

Abstract: Langmuir ion probe and in situ RHEED were applied to study the effects of low oxygen pressure on SrTiO3 (STO) film growth by Pulsed Laser Deposition (PLD). Contributions of different oxygen fluxes were analysed and parameters of STO epitaxial film growth were evaluated using physical model of adiabatic expansion of the ablation products and its interaction with ambient gas. Film surface undergoes reconstruction at growing temperatures >600 °C indicating complete or partial relaxation of top layer without changing growth mechanism of smooth multilayered film. All films have a tetrahedral lattice distortion in the direction of growth that varying with deposition temperature and oxygen pressure. STO lattice distortion is the relevant factor in determining both agility and dielectric loss for tuneable microwave devices. Annealing in oxygen at 1100 °C improves significantly functional properties of STO films, but only the layers deposited under the pressure lower than 10−3 Pa possesses low dielectric losses in combination with high agility. [Copyright &y& Elsevier]

Abstract: Short-time surface contact of highly diluted 1-monostearoylglycerol (1-MSG) aqueous solutions with highly oriented pyrolitic graphite results in the deposition of an epitaxial monolayer that can be detected by atomic force microscopy operating in tapping mode at the graphite–air interface. The monolayer obtained with the racemic mixture is then compared to that obtained with one of the pure enantiomers. The analogous behavior found for aqueous solutions of rac-1-MSG and 3-sn-MSG implies a two-dimensional self-assembly process with chiral discrimination. The results suggest that the monolayer originates from species located at the surface of the deposition drop. They also indicate that the simple experimental procedure reported, or more elaborate Langmuir–Schaefer methods, could be the method of choice to prepare other monolayers of similar surfactants. [Copyright &y& Elsevier]

Abstract: The effect of hafnium content on material properties of ultra-thin, mist deposited Hf-based dielectrics is investigated. Deposition rate and dielectric constant of HfSiO x film were found to increase with Hf content in the precursor. X-ray photoelectron spectroscopy and X-ray diffractometry revealed the presence of distinct Hf–O and Hf–Si–O phases in the HfSiO x film deposited with high-Hf content precursor. With an increase of Hf-content in the HfSiO x the equivalent oxide thickness value of the Pt–HfSiO x –Si gate stack was decreasing and leakage current maintained lower than that of HfO2 at the similar physical thickness. [Copyright &y& Elsevier]

Abstract: Silicon oxynitride thin films were deposited by radio frequency sputtering from silicon target and using various Ar–O2–N2 atmospheres. The target self bias voltage and the deposition rate were found to decrease abruptly when the oxygen flow rate reaches 0.55 sccm; this phenomenon is due to the oxidation of the target surface. When the oxygen content of the plasma is increased, the deposit composition varied from one close to Si3N4 to SiO2 one and the layer density decreased. These variations are accompanied by a shift of the infrared absorption peak towards higher wavenumbers. An estimation of the SiO and SiN bonding confirmed that the reactivity of oxygen with silicon is higher than the nitrogen one. The deposit structural defects were attributed to silicon neutral dangling bonds and the spin density was found to decrease with increasing the oxygen content. [Copyright &y& Elsevier]

Abstract: In this work we report the optical and structural properties of chemically deposited CdS films obtained from an ammonia-free chemical bath deposition process. The deposition process is based in the substitution of ammonia by sodium citrate as the complexing agent in the reaction solution. We applied spectroscopic ellipsometry and optical transmission and reflection spectroscopy to determine the thickness, optical constants and energy band gap of a set of CdS samples obtained by this process at different deposition times. Additionally, the spectroscopic ellipsometry analysis provided information about the microstructure and kinetic growth process of the CdS films. We found that experimental data fit quite well with a model of two different layers, corresponding to different growing stages, to simulate the CdS films. The first layer, formed at the earlier growing stages by means of the ion by ion deposition process, was assigned to a pure compact CdS layer and their optical properties were simulated by a Kramers–Kronig consistent model. The second external layer composed by a mixture of CdS and voids was modeled by the Bruggeman effective medium approximation. The results were compared to those obtained for a set of CdS samples obtained from a deposition process which employs ammonia in the reaction solution. [Copyright &y& Elsevier]

Abstract: The Single Pendulum Impact Scratch Test (SPIST) with high precision for measuring impact energy consumption during scratching has been developed. A new criterion for evaluating adhesion between coating and substrate has been suggested. Some super hard coating (TiN) deposited by physical vapor deposition and rather tough coating (Ni–P) prepared by electroless plating have been tested. The SPIST result of adhesion of TiN coating/substrate shows a good correspondence with that in the Acoustic Emission Monitoring Scratch Test (AEMST). The physical meaning of energy criterion from SPIST is more distinctive than that of the critical load from AEMST. The difficulty of weak or absent acoustic emission signal during the steady scratch test for evaluation of adhesion of tough coating/substrate could be overcome by SPIST and its result of Ni–P/1045 steel is also in consistence with that of Direct Pull-off test — a common method for evaluation of adhesion of plating or painting. [Copyright &y& Elsevier]

Abstract: Increasingly, organosilane self-assembled monolayers (SAMs) are used to modify the surfaces of silicon-based sensors and atomic force microscope (AFM) probes. Organosilane SAMs are preferred due to their fast and easy preparation, stability, and applicability to a wide range of substrates. The traditional dip coating method from solution often yields ill-defined particulate aggregates on the two-dimensional SAM. The presence of such three-dimensional aggregates seriously reduces the performance of miniaturized biosensor devices and AFM probes. It is difficult to control the amount of water in solution-based deposition. This paper describes a chemical vapor deposition (CVD) method to deposit octadecyltrichlorosilane (OTS) monolayers on silicon wafers and AFM probes under vacuum condition. OTS coated surfaces with static water contact angle ranging from 20° to 107° can be obtained by controlling the deposition conditions. The silicon substrates and AFM probes after CVD are characterized by AFM, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and contact angle goniometry. The OTS monolayer is in a uniform low-density state below 65%. Above 65%, densely packed crystalline-like domains start to form. It takes 24 h to reach the adsorption saturation. The time span in the CVD deposition is much longer than the solution case and thus allowing precise variation of the substrate hydrophobicity for biosensor applications. [Copyright &y& Elsevier]

Abstract: ZnS thin films have been deposited by chemical bath deposition method using tartaric acid as a complexing agent. The structural and morphological characteristics of films have been investigated by X-ray diffraction (XRD), scanning electron microscope and atomic force microscope analysis. XRD shows development of well-crystallized film with pure-wurtzite structure after annealing. The films show good optical properties with high transmittance in the visible region and the band gap value was estimated to be 3.69 eV. The photoluminescence spectrum of films has also been studied. [Copyright &y& Elsevier]

Abstract: Combustion chemical vapor deposition was used to synthesize α-alumina thin films. The deposition solutions were 0.0015 M aluminum acetylacetonate dissolved in isopropanol. Fused silica and nichrome (Ni–20Cr) served as substrates. Deposition temperatures were in the range of 1050 °C to 1125 °C. Crystalline films consisting of hexagonal α-grains were produced on both substrates. Some films on nichrome displayed preferred orientations of (113) and (116) normal to substrate surfaces, while films deposited on silica showed no preferred orientation. Films deposited on nichrome seemed denser than those on silica as the grains clustered together to provide a ‘cauliflower’ appearance. The oxidation response of uncoated and alumina-coated nichrome specimens was measured by isothermal thermogravimetric analysis in pure flowing air at 900 °C, 1000 °C and 1100 °C. The coated specimens had significantly lower mass gain values and parabolic rate constants than their uncoated counterparts. [Copyright &y& Elsevier]

Abstract: We show that the fiber axis orientation in sputtered aluminum nitride (AlN) responds strongly to deposition angle as compared with pure metal films. Fiber axis tilt was measured in films deposited at angles from 0° to 68° from the substrate normal. For pure metal films of Al and Ag, the strong (111) texture has a fiber axis tilt of <10° from the substrate normal. For pure Nb films, the strong (110) texture also has a tilt of <10°. In contrast, for films of the compound AlN, the distinct c-axis texture responds strongly to the deposition direction, with the fiber axis tilt almost following the deposition angle. [Copyright &y& Elsevier]

Abstract: Au–Pt core-shell nanoparticles were prepared on glass surface by a seed growth method. Gold nanoparticles were used as seeds and ascorbic acid–H2PtCl6 solutions as growth solutions to deposit Pt shell on the surface of gold nanoparticles. These core-shell nanoparticles and their growth process were examined by UV–Vis spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and field-emission environmental scanning electron microscopy and the results indicated that the deposition speed was fast and nanoparticles with obvious core-shell structure could be obtained after 2 min. Moreover, this seed growth method for preparation of the core-shell nanoparticles is simple and convenient compared with other seed growth methods with NH4OH as a mild reductant. In addition, electrochemical experiments indicated that these Au–Pt core-shell nanoparticles had similar electrochemical properties to those of the bulk Pt electrode. [Copyright &y& Elsevier]

Abstract: Photocatalytically active TiO2 thin-films were deposited on silicon wafers using the Successive-Ionic-Layer-Adsorption-and-Reaction technique and subsequent hydrothermal and/or furnace annealing. Atomic-force-microscopy images and X-ray diffraction measurements of the TiO2 films obtained under various annealing conditions show how changes of the micro-scale surface structure depend on the post-SILAR treatment. The hydrogen evolution over various TiO2 films was measured. Hydrothermally treated TiO2 films show a higher photocatalytic activity and a much better mechanical stability compared to furnace-annealed films. The optical transmittance of TiO2 thin films on glass substrates was also studied. A red shift was observed with increasing film thickness. TiO2 nanoparticles (∼10nm) that were peeled off from the TiO2 films were investigated using high-resolution-transmission-electron-microscopy. [Copyright &y& Elsevier]

Abstract: A technique is presented for sub-nanometre correction of precision-polished optical surfaces. The technique uses thin metallic masks with multiple apertures of varying widths to selectively occlude a beam of depositing species in an ion beam sputtering system. The masks are designed directly from measured surface profile maps of the optical surface, and are fabricated using well-established laser-cutting technology commonly used to fabricate solder masks for the semiconductor industry. The selective deposition has proved highly effective for fabrication of large-aperture Fabry–Perot filters and has resulted in optical uniformities of less then 0.3 nm rms over a clear aperture of 37.5 mm. This manuscript will give details of the mask design, deposition technique, and results from recent surface correction runs. [Copyright &y& Elsevier]

Abstract: The crystal structure of a conjugated molecule containing thiophene and fluorenone residues has been determined from powder X-ray diffraction (XRD). Thin films (<40 nm thick) of this molecule, grown in high vacuum (10−5 Pa) onto oxidized silicon substrates, are oriented along with different crystallographic directions. A comparison of XRD in both Grazing Incidence and Bragg–Brentano geometries allowed to perform a quantitative analysis of the various orientations. This approach is generally applicable in the case of multi-oriented films. The results fully account for the poor performance of this molecule in p-type field effect transistor devices. [Copyright &y& Elsevier]