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Abstract A crack-free and dense, yet thick lead lanthanum zirconium titanate (PLZT; P 0.92 L 0.08 Z 0.65 T 0.35) film was achieved by single-step, non-repetitive spin-coating of PLZT sol-gel chemically modified with poly(vinylpyrrolidone) (PVP). Incorporation of PVP into the precursor solution could be highly beneficial for prohibiting cracks during the condensation reaction of spin-cast gel film and controlling the film thickness. Close examination by using optical microscopy, X-ray diffraction, Raman spectroscopy, and scanning electron microscopy enabled compositional and structural characterization of PLZT films on both transparent sapphire and flexible plastic substrates before and after the laser lift-off process. Such dense and crack-free PLZT film with thickness ranging from 2.5 to 3.4 μm was successfully applied for fabricating flexible piezoelectric energy harvester. This study can be further extended to prepare other crack-free, dense piezoelectric films, thus offering a facile and robust pathway to the fabrication of the piezoelectric energy harvesting devices. Highlights • A versatile approach for micrometer thick and crack-free piezoelectric film is proposed. • Cracks are prohibited by incorporation of poly(vinylpyrrolidone) (PVP) into the precursor solution. • The lead lanthanum zirconium titanate (PLZT) film is safely transferred on to a flexible substrate. • A flexible PLZT piezoelectric energy harvester is fabricated. [ABSTRACT FROM AUTHOR]

Abstract Ni/Ni-Cr thin film thermocouples were deposited by means of DC magnetron sputtering for the application in plastic extrusion dies. In order to ensure the application of the thermocouples on complex surfaces, a thermally sprayed Al 2 O 3 layer was used between the substrate and the thin films for thermal insulation and electrical isolation. The study includes the deposition, characterization, calibration, and validation of thin film thermocouples. The influence of the composition (10 at.-%, 20 at.-% and 30 at.-% Cr) was analyzed concerning mechanical and electrical properties. It was found out that the electrical resistance increases with the temperature and the Cr-content due to a decreasing crystallite size. By means of a scratch-tester and nanoindentation, a higher scratch load and hardness were observed for larger Cr-contents on the thermally sprayed Al 2 O 3 coating. Despite the composition, the influence of the size as well as the thickness of the thermocouples were analyzed regarding the Seebeck coefficient. Independent from the size and Cr-content, all thermocouples feature a comparable Seebeck coefficient of about 40 μV/K. This high coefficient is similar to that of wire thermocouples, showing a low number of defects in the thin films. The ceramic coating features a thermal insulation of about 20 °C at 200 °C, allowing a more accurate measurement of the ambient medium. Highlights • Ni/Ni(10,20,30)Cr thin film thermocouples were deposited on thermally sprayed Al 2 O 3. • The thermocouples were deposited with different sensor sizes and calibrated. • The Al 2 O 3 coating reduces the temperature influence of the substrate. • All Ni Cr alloys show a comparable high Seebeck coefficient of 40 μV/K. [ABSTRACT FROM AUTHOR]

Abstract Zinc oxide films with a high transmittance in the visible range (over 80%) were obtained by successive ionic layer adsorption and reaction method without thermal treatment, using only a low-temperature (125 °C) ethylene glycol bath to complete the reaction. It was shown that the film deposition rate, as well as its structural and optical properties can be adjusted by variation of NH 4 OH concentration in the precursor solution. All obtained films were of a uniform surface morphology with fine grains about 43–48 nm in size and larger flower-like surface formations. The complex multi-technique material characterization has shown that ZnO deposited from 1:20 ZnSO 4 :NH 4 OH precursor solution featured low content of residual phases, faster growing rate, higher c -axis orientation, and the highest transparency. At the same time, optical band gap of the samples (E g ≈ 3.4 eV) showed no marked dependence on NH 4 OH concentration. Highlights • A method to grow ZnO thin films at low temperature by SILAR is proposed. • No post-deposition anneal treatment is necessary to obtain crystallized ZnO thin films. • ZnO film properties are related to NH4OH concentration in the precursor solution. [ABSTRACT FROM AUTHOR]

Al 2 O 3 thin films were deposited by plasma-enhanced chemical vapor deposition using a dimethylaluminum isopropoxide precursor in the absence of additional oxygen sources. The deposition rate ranged from 0.77 to 1.07 Å/s and increased with increasing deposition temperature between 300 and 500 °C. The O/Al ratios in the films deposited at 300–500 °C were ~ 1.5, consistent with the formula Al 2 O 3 and the carbon contents were 8.3–9.7 at.%. The film deposited at 30 °C had relatively higher values of O/Al ratio (2.04) and carbon content (47.1 at.%). Al2p, O1s, and C1s peaks observed from X-ray photoelectron spectroscopy analysis were mainly attributed to Al 2 O 3 . Fourier transform infrared analyses indicated that the functional groups such as Al 2 O 3 bending and stretching vibrations were primarily from Al 2 O 3 species with some carbon contents. From the dry etching test, the Al 2 O 3 film deposited at 400 °C had the high etch selectivity of 9.13 over SiO 2 , which showed the potential for application to the dry etch hard mask material. [ABSTRACT FROM AUTHOR]

Recently, Gd 2 Zr 2 O 7 has been investigated as a buffer layer of YBa 2 Cu 3 O 7 − x superconductor. Thermal properties of Gd 2 Zr 2 O 7 below room temperature are not well known yet despite of its active studies. For the study of the thermal property at low temperature, the Gd 2 Zr 2 O 7 films with various thicknesses are deposited on the Al 2 O 3 substrate by using the RF magnetron sputtering. Thermal conductivities of Gd 2 Zr 2 O 7 thin films are measured by using the 3 omega method from 80 K to room temperature. We confirm the interfacial thermal resistance and its temperature dependence. The interfacial thermal resistance decreases with increasing temperature unlike the reported temperature dependence of the thermal conductivity. The importance of interfacial effect on the thermal conductivity is being emphasized at very low temperatures. [ABSTRACT FROM AUTHOR]

This work demonstrates the formation of few-layer graphene flake structures directly from graphite particles. A nano-particle deposition system, which is a dry spray deposition method generally used for deposition of metals and ceramics, has been introduced to deposit graphite particles at room temperature. In this study, graphite powder was deposited on a Cu substrate without using binders and the deposited thin film was characterized. The deposited thin film contained few-layer graphene flake structures, as observed using field effect scanning electron microscopy and confirmed using X-ray diffraction, Raman spectroscopy and field emission transmission electron microscopy. We also suggested the critical impact velocity for deposition of few-layer graphene flake structured thin film and a mechanism for forming few-layer graphene flake structures during thin film preparation. The suggested mechanism was interlayer separation of micron-sized graphite particles and fragmentation of particles into small pieces during deposition due to the impact of graphite particles on the substrate. [ABSTRACT FROM AUTHOR]

Hydrogenated amorphous silicon carbide (a-SiC:H) films, which contain sp 3 hybridized carbon phase embedded in a-SiC:H matrix were fabricated by a radio frequency (13.56 MHz) plasma enhanced chemical vapor deposition (PECVD) system with methane and silane mixture (silane diluted by H 2 , volume ratio: 90% H 2 + 10% SiH 4 ) as reactive precursor gases. It was found that under the deposition conditions of fixed the RF power density, pressure, deposition temperature and silane mixture flow rate, the flow rate of methane (R) had a large impact on the content of sp 3 hybridized carbon phase and surface morphology of the a-SiC:H thin films. The research shows that the silicon bonding environment didn't change with increasing R and the H bonded to sp 3 hybridized carbon phase mainly derived from the CH n radicals generated by decomposition of CH 4 rather than H 2 . Simultaneously, the methane flow rates can control the deposition rate and surface morphology of the a-SiC:H films and make the films become more compact and uniform. [ABSTRACT FROM AUTHOR]

Influence of blocking oxide layer types on the performance of nonvolatile floating gate memory (NFGM) containing AgInSbTe (AIST)-SiO 2 nanocomposite as the charge-trapping layer was investigated. In the NFGM containing a 7-nm thick SiO 2 blocking oxide layer deposited by plasma-enhanced chemical vapor deposition (PECVD), a fairly large memory window (Δ V FB ) shift of 20.9 V with the charge density of 1.3 × 10 13 cm − 2 at ± 15 V gate voltage sweep was achieved. As to the NFGM containing HfO 2 blocking oxide layer, the device performance was inferior to that of PECVD-SiO 2 device due to the diffusion of HfO 2 into the nanocomposite layer. Interdiffusion resulted in the formation of HfSiO x phase and oxygen defects which might act as the leakage paths, consequently deteriorating the charge trapping efficiency of AIST nanocrystals (NCs) embedded in nanocomposite layer. Analytical results illustrated that the film quality and barrier height feature of blocking oxide layer are essential to form the deep trap sites in the programming layer to achieve a satisfactory NFGM performance with long-term reliability. [ABSTRACT FROM AUTHOR]

A solid-state sensor based on a polytyramine (Pty) film deposited on a glassy carbon electrode doped with a tris(2,2'-bipyridyl)Ru(II) complex (Ru/Pty/GCE) was constructed electrochemically. The surface morphology of the film modified electrode was characterized using electrochemical and surface scanning techniques. A redox property represented by a [Ru(bpy)3]3+/2+ couple immobilized at the Pty moiety was characterized using typical voltammetric techniques. A distinct Ru 3d peak obtained at 280.9eV confirms doping of the Ru species onto the Pty moiety characterized by X-ray photoelectron (XPS). Atomic force microscopy (AFM) images demonstrate that incorporation of Ru decreases the surface roughness of the native Pty film modified electrode. The Ru/Pty/GCE exhibits efficient electrochemical sensing toward the oxidation of dopamine (DA), ascorbic acid (AA) and uric acid (UA) in their mixture. Three well-defined peaks were resolved with a large peak to peak separation and the detection limits of AA, DA and UA are brought down to 0.31, 0.08 and 0.58μM, respectively. Interference studies and application for DA determination in real samples were conducted with satisfactory results. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report on an experimental analysis of dimension effect on a room-temperature electrical oscillation in a planar device using vanadium dioxide (VO2) thin film. We investigate the variation of the oscillation current (I O) and frequency (f O) due to the variation of the dimension of the VO2 devices, i.e., the length and width of the current channel of the device. For five different VO2 devices with different dimensions, I O and f O are observed at room temperature in a simple circuit composed of a dc voltage source and a standard resistor including one of the VO2 devices. From the experimental investigation, it is concluded that the peak-to-peak amplitude of I O and f O decrease with the increase of the length and width of the current channel. This indicates that f O depends on not only the external source voltage but also the device dimension. [Copyright &y& Elsevier]

Abstract: Porous thin films deposited by glancing-angle deposition (GLAD) have found application as sensor, micro-electrical mechanical systems and microfluidic devices. However, conventional micro-fabrication techniques can damage the very properties which make GLAD films attractive for these applications. To facilitate integration of GLAD films with these processes, a capping layer may be used. Such capping layers must be as free of defects as possible to ensure that the GLAD film is well protected. Here, the cracking properties of evaporated TiO2 caps deposited on GLAD films have been investigated as a function of substrate temperature. Our films are a porous vertical post layer 2.7μm thick capped with a solid 400nm layer. This material system experiences tensile stress from two sources: thermal mismatch between the film and substrate, and intrinsic stress in the cap from Volmer–Weber coalescence. Crack properties such as crack length distribution, crack density and branch number were quantified. In general, higher substrate temperatures reduced crack density, branch number and preferentially eliminated longer cracks. The onset of crystallinity at substrate temperatures around 300°C briefly increases crack area and branch number, but a further reduction can be achieved by depositing above this temperature. Applications of films grown by GLAD requiring high-quality capping layers will benefit from this study. [ABSTRACT FROM AUTHOR]

Abstract: Wurtzite Mg x Zn1−x O thin films were grown on sapphire substrates by low-pressure metal-organic chemical vapor deposition. The as-grown films show clear exciton absorption at room temperature until the composition x =0.25. A representative metal–semiconductor–metal structured photodetectors were fabricated from Mg0.06Zn0.94O film showed a peak responsivity of about 14.62 A/W at 340nm, and the ultraviolet-visible rejection ratio (R340 nm/R400 nm) was more than two orders of magnitude at 3V bias. The photodetector showed fast photoresponse with a rise time of 20ns and a fall time of 400ns. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the study on characterizing the mechanical and interfacial properties of ruthenium dioxide (RuO2) film on silicon substrate using nanoindentation tests. RuO2 film is deposited by DC reactive magnetron sputtering; the structure and morphology of the film are characterized using X-ray diffraction and scanning electron microscopy, and elastic modulus and hardness are determined by nanoindentation with a standard Berkovich indenter and found to be 232.74±22.03GPa and 20.43±2.37GPa, respectively. In addition, the interfacial adhesion properties of RuO2 film on Si substrate are studied. Spontaneous interfacial delamination is induced by indentations with wedge (90° and 120°) and conical indenter tips. The relationship between the indentation load-displacement (P-h) curves and the interfacial crack initiation and propagation are analyzed by combining FIB sectioning and SEM imaging. Through this analysis, the interface toughness of as-deposited RuO2 film is found to be 0.046±0.003J/m2 for 90° wedge indentation, 0.050±0.004J/m2 for 120° wedge indentation, and 0.051±0.003J/m2 for conical indentation. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the imidization temperature on the molecular structure and on the thermal and electrical properties of polyimide thin films is investigated. The effects of the imidization temperature on the formation of the imide rings are studied by Fourier transform infrared (FTIR) spectroscopy through the changes of the extent of imidization. However, the determination of the optimal imidization temperature shows a poor accuracy through this technique. Therefore, the quantification of several electrical properties used as probes of the imidization reaction advancement (particularly high field electrical measurements) allows obtaining a highest accuracy of the optimal imidization temperature. An optimum temperature is found at 400°C while desimidization is observed at 450°C. This is in good agreement with FTIR results. [ABSTRACT FROM AUTHOR]

Abstract: Ultrasonical colloid chemistry deposition (UCCD) has been widely used to fabricate columnar-structured cadmium sulfide (CdS) thin films with ultra-fine particles. In conventional UCCD, the ultrasonic source is installed outside the reaction bath. In this study, an ultrasonic homogenizer was used as the ultrasonic source and was immersed directly in the bulk solution. The advantages of the ultrasonic homogenizer include homogeneous deposition, fine mixing, and enhancement of the ion-by-ion reaction. We compared the physical properties of CdS thin films prepared with and without ultrasound by using an X-ray diffraction, scanning electron microscope, atomic force microscope, and 3D surface analyzer and UV–Vis–NIR measurements. [ABSTRACT FROM AUTHOR]

Abstract: When colloidal crystal films are deposited onto nanocrystalline porous substrates by the commonly used colloidal crystallization method of vertical deposition self-assembly, the colloidal crystal tends to be poorly adhered to the porous film. Herein, we present a fabrication of large-area, three-dimensional (3D) colloidal crystal thin films on nanocrystalline porous substrates by a room temperature floating self-assembly method that has recently been developed for colloidal crystal deposition. Firstly, colloidal suspensions were prepared by dispersing monodisperse colloidal microspheres at high volume fraction in a mixture of ethanol and water. At room temperature, these suspensions were spread onto nanocrystalline porous TiO2 films. The colloidal particles assembled into 3D ordered structures at the air−liquid interface of the suspensions as a result of rapid evaporation of the solvents. After the solvents (water and ethanol) had evaporated completely, the colloidal crystals were directly deposited on the nanocrystalline porous TiO2 films. Scanning electron microscopy images and normal-incidence transmission spectra of the samples showed that the colloidal crystal films deposited on the nanocrystalline porous TiO2 substrates by this method had very high crystalline quality. In addition, the effect of the degree of surface roughness of the nanocrystalline porous substrate on the crystalline quality of the colloidal crystals has been studied. [ABSTRACT FROM AUTHOR]

Abstract: Influence of substrate temperature and Zn-precursors on growth rate, crystal structure, and electrical property of undoped ZnO thin films grown by atomic layer deposition (ALD) have been studied. Differences between dimethylzinc (DMeZn) and diethylzinc (DEtZn) used as Zn-precursors were examined. The ZnO films grown using DMeZn showed higher electrical resistivity compared to that grown using DEtZn. However, the higher resistivity in the case of DMeZn was owing to much amount of residual impurities incorporated during the ALD growth. [Copyright &y& Elsevier]

Abstract: We have grown a tensile-strained Ge layer on a strain-relaxed compositionally step-graded Ge1− x Sn x buffer layer using virtual Ge substrates. The degree of strain relaxation along [110] direction of the top Ge0.945Sn0.055 buffer layer is achieved up to 85% and the resultant (110) lattice spacing of the Ge0.945Sn0.055 buffer layer is estimated to be 0.4028 nm. A pseudomorphic Ge layer is successfully grown on the Ge0.945Sn0.055 buffer layer, yielding a tensile strain of 0.68% with respect to the (110) lattice spacing of non-strained Ge. This value exceeds those obtained by other methods based on the thermal expansion coefficient difference and strain-relaxed Ge1− x Sn x buffer layer directly grown on Si(001) substrates. [Copyright &y& Elsevier]

Abstract: A study of changes in nano-scale morphology of thin films of nano-crystalline transition metal (TM) elemental oxides, HfO2 and TiO2, on plasma-nitrided Ge(100) substrates, and Si(100) substrates with ultra-thin (∼0.8 nm) plasma-nitrided Si suboxide, SiO x , x <2, or SiON interfacial layers is presented. Near edge X-ray absorption spectroscopy (NEXAS) has been used to determine nano-scale morphology of these films by Jahn–Teller distortion removal of band-edge d-state degeneracies. These results identify a new and novel application for NEXAS based on the resonant character of the respective O K1 and N K1 edge absorptions. Their X-ray energy difference of >150 eV is critical for this approach. [Copyright &y& Elsevier]

Abstract: In this paper we investigate the third-order nonlinear optical properties of spin deposited thin films of DNA-based complexes using the optical third harmonic generation (THG) technique at a fundamental wavelength of 1064 nm. We found that the third-order susceptibility, χ (3)(− 3ω;ω,ω,ω), of DNA-based films was about one order of magnitude larger than that of our reference, a pure silica slab. In thin films doped with 5% of the chromophore disperse red 1 (DR1), a two order of magnitude larger value of χ (3)(− 3ω;ω,ω,ω) was observed. [Copyright &y& Elsevier]

Abstract: In this work, the main problems concerning the scattering of light by real surfaces and films are presented in view of results obtained with the bidirectional reflection distribution function (BRDF) method and optical profilometry (OP). The BRDF and OP studies, being complementary to the atomic force microscopy (AFM), allow one to get information about surface topography. From the optical data, the surface power spectral density (PSD) functions for absorbing and transparent rough films have been found. Both functions have been evaluated from the Fourier transform (FT) of the surface profiles. The usefulness of BRDF-and OP methods in characterization of real surfaces is demonstrated when analyzing the optical data obtained for metallic TiN-and organic PVK thin films deposited on various substrates. [Copyright &y& Elsevier]

Abstract: We report the characterization of two-dimensional silicon photonic crystals using angular-dependent reflectivity in the mid-IR. The photonic crystals are obtained by electrochemical etching of an ordered array of holes into silicon. The measurements are compared with the theoretical calculations of the corresponding model based on the interaction of the incident light with the photonic crystal sample. A good agreement between the measurements and the calculations is achieved. [Copyright &y& Elsevier]

Abstract: Tip-Enhanced Raman Spectroscopy is based on the field enhancement and confinement provided by sharp metallic tips, used to locally excite the Raman emission from molecules, crystals and nanostructures. This technique has recently demonstrated capabilities for nanometer scale optical resolution in Raman analysis and has enormous potential applications in nano- and bio-technologies. In this paper we describe the state-of-the-art experimental techniques, focusing the attention on the strategies to reduce the far-field background, on new processes to fabricate sharp metallic tips and on the effect of the depolarization produced by metallic tips on Tip-Enhanced Raman spectra of bulk crystals. [Copyright &y& Elsevier]

Abstract: In narrow-gap semiconductors, non-radiative Auger recombination losses (via conduction, heavy-hole, spin split-off hole, heavy-hole processes) are sensitive to how the band gap energy, E 0, compares to the spin-orbit splitting, Δ 0. However, narrow-gap band structures have often not been very well characterised. We report on the mid-infrared photo-modulated reflectance of E 0 and E 0 + Δ 0 transitions in high-quality, InAs-rich InAsSb and GaInAsPSb samples as functions of both temperature (T =10–300 K) and antimony content ≤22.5%, for wavelengths up to ~4.75 μm. The measured T-dependence of E 0 is generally consistent with that accepted in the literature and we confirm that Δ 0 is T-independent. As a function of Sb fraction, E 0 is consistent with the positive bowing parameter of +670 meV quoted in the literature. However, Δ 0 does not exhibit the currently accepted positive bowing parameter of +1170 meV: rather, a best fit to our data tentatively suggests a negative bowing of ~−165 meV. Due to the importance of Δ 0 in predicting and interpreting the performance of InAsSb-based devices, this result is expected to have a significant impact. [Copyright &y& Elsevier]

Abstract: Ti–Ni–Cu shape-memory alloy (SMA) thin films were sputter-deposited on heated polyimide substrates. Ti–Ni–Cu films deposited at substrate temperatures of 543 and 583 K were found to be crystalline. Especially, a Ti48Ni29Cu23 film deposited at 583 K exhibited a high martensitic transformation temperature above room temperature and a narrow transformation temperature range, which enable the film to be used at room temperature. Double-beam cantilevers made of 8 μm thick Ti48Ni29Cu23 films deposited on 12.5 and 25 μm thick polyimide substrates displayed a repeatable shape-memory effect by a battery of 1.5 V and it was verified that the composite film consisting of an 8 μm thick Ti48Ni29Cu23 film and a 25 μm thick polyimide film is capable of moving 0.18 g wings of a dragonfly toy up and down. These results offer the prospect for using an SMA/polyimide actuator as a convenient small actuator, which will find wide-ranging applications. [Copyright &y& Elsevier]

Abstract: Thin silicon nitride films have been deposited by a low temperature (20 °C) Electron Cyclotron Resonance (ECR) plasma directly on Si substrates. Varying the process pressure, gas composition and radio frequency bias power, films with different properties were obtained. Characterization by Fourier transform infra-red spectrometry reveals the presence of Si–N, Si–H and N–H bonds in the films. Refractive indexes in the range from 1.77 to 2.9 and deposition rates from 13 to 18 nm/min were determined by ellipsometry. Buffered hydrofluoric acid (BHF) etch rates from 0.7 to 509 nm/min, and KOH etch rates lower than 1 nm/min were obtained. Optical emission spectroscopy showed a strong correlation between the concentration of NH molecules produced in the plasma and porosity of the films. Finally, the films that presented high resistance to etching in KOH and BHF were used to fabricate suspended membranes on Si substrates. With these results, the ECR plasma produced SiN x films that have been used for fabrication of membranes in microelectromechanical systems. [Copyright &y& Elsevier]

Abstract: Indium sulfide thin films were deposited onto indium-tin-oxide coated glass substrate by electrochemical deposition from an aqueous solution containing In2 (SO4) 3 and Na2S2O3. The deposition conditions were optimized on the basis of data obtained by scanning electron microscope, Auger electron spectroscopy and optical transmission measurements. Furthermore, the photosensitivity of the films was observed by means of photoelectrochemical measurements, which confirmed that the indium sulfide showed n-type conduction. The X-ray diffraction and Raman studies revealed that the as-grown films were amorphous or nanocrystalline in nature and became polycrystalline In2S3 after annealing. [Copyright &y& Elsevier]

Abstract: HgTe nanocrystal-based thin film transistors were fabricated on flexible polyethersulfone substrates and their electrical properties were characterized. Hydrophilic Al2O3 buffer layers were first deposited on the flexible substrates and HgTe nanocrystal films were then formed on top of the buffer layers. A representative top-gate flexible thin film transistor with a channel composed of a HgTe nanocrystal film functioned as a p-channel transistor and exhibited a mobility of ~1.20 cm2/V∙s and an on/off current ratio of ~1×103. [Copyright &y& Elsevier]

Abstract: Material removal rate, coefficient of friction, shear force and variance of shear force of pure and contaminated slurries are studied using spectral analysis of the frictional force. Larger abrasive particles are introduced into commercially available inter layer dielectric chemical mechanical planarization slurry to explore this effect. Results show that trace amounts of larger abrasive particles are transported effectively to the pad–wafer region during polishing. With certain type of consumables investigated in this study, results indicate that contaminated slurry does not significantly change removal rate, however it induces significantly higher coefficient of friction, shear force and variance of shear force than pure slurry. Spectral analysis based on the raw shear force data is employed to elucidate the fundamental physical phenomena during inter layer dielectric chemical mechanical planarization. Fast Fourier Transformation is performed to convert the shear force data from time domain to frequency domain. The energy distribution of polishing using pure and contaminated slurry is quantified to elucidate the effect of trace amount of larger particles. This work also underscores the importance of real-time detection on chemical mechanical planarization process to detect slurries abnormality. [Copyright &y& Elsevier]

Abstract: Titania thin films were prepared on bare Si and Pt/Ti/SiO2/Si substrates by chemical bath deposition (CBD) from solutions of a titanium peroxo complex and subsequent calcinations at 350 and 700 °C, respectively. The CBD process allowed deposition on both uncoated and metal-coated Si substrates with the same deposition rate. Optimization of the annealing process yielded uniform and crack-free nanocrystalline anatase films. The influence of the film thickness, irradiation of visible light, measuring frequency, temperature and substrate on the dielectric properties will be discussed in the paper. Films with a final thickness of about 600 nm showed comparably high relative permittivity of 31.8 on silicon and of 52.7 on Pt/Ti/SiO2/Si substrates, respectively. The present route provides anatase thin films with higher dielectric constants than classical sol–gel routes and is therefore a promising candidate for potential applications in large scale integration. [Copyright &y& Elsevier]

Abstract: Silver nanocrystals with the average diameter down to 4 nm were synthesized in Al2O3 matrix on Si substrate by pulse laser deposition followed by annealing at 400 °C in N2 ambient. A photoluminescence (PL) band centered at 2.27 eV was recorded. A model based on the PL spectrum induced by the radiative recombination of sp-band electrons with d-band holes in the silver nanocrystals is suggested. Metal-insulator-semiconductor structures with Silver nanocrystals embedded in Al2O3 gate dielectric were fabricated. Large hysteresis behaviour in terms of large memory window and good data retention were characterized by capacitance–voltage and capacitance–time measurements. [Copyright &y& Elsevier]

Abstract: We presented a magnetic force microscopy and vibrating sample magnetometer study of perpendicular anisotropy of [Co t /Fe3t ]5 (t =2, 3, 4, 5 nm) multilayers prepared by direct current magnetron sputtering on glass and Si substrates. It was found that except for the specimens with t =2 nm, most specimens exhibited obvious weak perpendicular anisotropy. By analyzing the anisotropy field and the root-mean-square roughness of phase shift of magnetic force images, we compared the perpendicular anisotropy among the multilayers deposited on Si and glass substrates. As a result, it is concluded that the primary origin of the weak perpendicular anisotropy can be attributed to the compressive stress induced by the lattice mismatch between Fe and Co layers. [Copyright &y& Elsevier]

Abstract: The nanostructured solid solution Ti0.5Al0.5N thin film (∼1.2 μm in thickness) was prepared on Si (100) substrates by reactive close-field unbalanced magnetron sputtering at a bias voltage of −50 V in an Ar–N2 gas mixture. The deformation behavior of the film was systematically investigated by nanoindentation measurements. Analyses of the obtained load–displacement curves showed no evidence of a “staircase” discontinuity in the specimen and the effect of the tip radius of the indenter on the behavior of elastic and plastic deformation can be determined. The critical shear stress, yielding strength and the size of plastic zone of the Ti0.5Al0.5N thin film under nanoindentation were evaluated by integrating the Hertzian stress analysis and the Johnson''s cavity model. Results revealed that the new complete dislocation nucleation during indentation was not the prerequisite for the onset of plastic deformation, which met Von Mises yielding criteria. The relationship between the normalized plastic zone size and loading rates was also established. It was suggested that the ability of plastic deformation of the Ti0.5Al0.5N thin film under nanoindentation was sensitive to the loading rates, which is attributed to the metastable crystalline structure of thin film. [Copyright &y& Elsevier]

Abstract: Nanoindentation has been widely used to evaluate material properties. In this study, we propose a method that utilizes only the loading curves of an indentation test to extract the elastoplastic properties of an elastic-perfectly plastic thin film as well as the plastic properties of a work hardening thin film. The use of loading curve circumvents some common difficulties encountered during the post-processing of experimental unloading curves. Measurements are taken at two different indentation depths, which have different levels of substrate effects and lead to the establishment of independent equations that correlate the material properties with indentation responses. Effective reverse analysis algorithms are proposed by following which the desired film properties can be determined from a sharp indentation test. The extracted material properties agree well with that measured from a bulge test. [Copyright &y& Elsevier]

Abstract: By means of X-ray photoemission spectroscopy and low energy electron diffraction, we show that it is possible to grow good quality thin epitaxial CoO films on Fe(001) substrates, through deposition in oxygen atmosphere. In particular, the composition and the structure of CoO(001)/Fe(001) bilayer systems and Fe(001)/CoO(001)/Fe(001) trilayer systems have been investigated by monitoring the evolution of the chemical interactions at the interfaces as a function of CoO thickness and growth temperature. We observe the presence of Fe oxides at the CoO/Fe interface and of a thin layer of metallic cobalt at the upper Fe/CoO interface of trilayer systems. [Copyright &y& Elsevier]

Abstract: Change of electronic structure and chemical composition on the surface of freshly prepared As35S65 thin films caused by electron- and light irradiation have been studied by high-resolution X-ray photoelectron spectroscopy. The mechanisms of the induced transformations are compared. It is shown that light irradiation causes redistribution of chemical bonds without change in chemical composition. The products of such light-induced structural transformations were also identified by Raman spectroscopy in the volume of thin films. Electron irradiation changes chemical composition of the surface by creating an As-enriched layer due to the formation of As–O bonds. Anomalous increase of the ~10 eV band associated with non-bonding As 4s electrons was observed after light- and low dose e-beam irradiation. [Copyright &y& Elsevier]

Abstract: Polarized light emission has various potential uses in electro-optic applications such as providing backlighting for liquid crystal displays without a loss of brightness. This study examined the highly polarized light emission of a thienothiophene-based oligomer, 2,5-bis-(4-biphenylyl)-thieno[3,2-b]thiophene (BPTT), deposited on a friction-transferred polymer film. The BPTT film showed a high polarization ratio of more than 6 by alignment of the backbone of the molecule along the friction-transfer direction of the polymer chain. A strong correlation between the photoluminescent spectrum and the morphology of the film also was observed. [Copyright &y& Elsevier]

Abstract: We employ textured α-Cr2O3 thin films as templates for growth of α-Al2O3 by reactive inductively coupled plasma magnetron sputtering. The texture of the template has a strong influence on the nucleation and growth of α-Al2O3. Extended growth of α-Al2O3 at a substrate temperature of 450 °C is obtained using a predominantly [101̄4]-textured α-Cr2O3 template layer, while only limited α-Al2O3 nucleation is seen on a [0001]-textured α-Cr2O3 template. [Copyright &y& Elsevier]

Abstract: GaFeO3 thin films were prepared on MgO(001), Al2O3(0001) and fused quartz substrates by the pulsed laser deposition technique. The lattice match mechanisms between GaFeO3 thin films and substrates have been analyzed. Results of optical properties analysis show that the thin films have the different band gaps and optical properties. These differences can be ascribed to the different lattice strains induced by the different lattice mismatch and thermal expansion coefficients between the GaFeO3 thin films and the substrates. [Copyright &y& Elsevier]

Abstract: Surface polymerization by ion-assisted deposition was used to grow phenylene vinylene films (SPIAD-PPV) using the evaporation of 2-methoxy-5-(2''-ethylhexyloxy)-1,4-bis((4'',4"-bisstyryl) benzene) (MEH-OPV5) and the simultaneous deposition of non-mass-selected 10–200 eV thiophene or acetylene ions. Images recorded by scanning electron microscopy showed differences in SPIAD-PPV film morphology versus evaporated MEH-OPV5 that indicated changes in the underlying chemical structure. Spectroscopic differences between MEH-OPV5 and SPIAD-PPV films suggested preferential attack of vinylene groups and/or hydrocarbon side chains. A possible explanation for the changes in morphology and electronic structure was cross-linking at vinylene sites of adjacent MEH-OPV5 molecules which could lead to changes in molecular packing. Although morphological and electronic differences were seen for SPIAD-PPV films, these films still showed valence bands characteristic of phenylene vinylenes. [Copyright &y& Elsevier]

Abstract: A comprehensive study of the effect of cadmium sources on chemical bath deposited cadmium sulfide thin films is reported. Four different cadmium sources; cadmium sulfate, cadmium chloride, cadmium iodide, and cadmium acetate have been used. The effect of cadmium sources on film optical/electrical properties as well as film thickness, composition, crystal structure, and surface morphology was studied. Film growth rate and band gap were found to be sensitive to the Cd source used. Films were found to be highly stoichiometric when cadmium chloride and cadmium iodide were used. The lowest resistivity and highest mobility and band gap obtained were in the case of cadmium sulfate. All films were found to be cubic, regardless of the Cd salt used. [Copyright &y& Elsevier]

Abstract: Layers of CuIn0.7Ga0.3Se2 have been prepared by a CSVT technique on which improvements have been brought, permitting a better control of the growth conditions and reducing the cost of the installation. The effect of the substrate temperature on the composition of the layers and on their structural, morphological and electrical properties is discussed. The X-ray analysis shows that the crystalline state of the layers depends on the substrate temperature and especially on the gradient of temperature between the substrate and the source. A preferential (112) orientation and a more pronounced columnar structure are observed for the higher source–substrate gradient temperature. Electrical resistivity shows a change of two orders of magnitude, from 0.29 to 25.1 Ω cm, when the substrate temperature varies from 405 °C to 460 °C. Mott type variable range hopping conduction between 77 and 200 K is observed for samples grown at substrate temperatures higher than 405 °C. [Copyright &y& Elsevier]

Abstract: Electrodeposited CuIn(S,Se)2 based solar cells with efficiencies of 10.4% and 7.1% are reported. Their electronic transport properties are examined as a function of temperature by admittance spectroscopy and dark-current–voltage measurements (J (V, T)). For all devices, admittance spectroscopy reveals two relative shallow defect levels located at 0.1 eV and 0.23 eV, respectively. For the device showing the lowest efficiency, an additional deep defect at 0.51 eV is probed. The presence of this defect is well correlated with the J (V, T) results which reveal an enhancement of a second recombination mechanism that we identify as an additional tunneling-assisted recombination path. [Copyright &y& Elsevier]

Abstract: Different heterostructures, MOVPE grown by TBAs and TBP, lattice-matched to GaAs and containing a sequence of InGaP/GaAs quantum wells (QWs), were studied for the development of novel photovoltaic devices. Their structural characterisation exhibited a low structural and compositional disorder with a low defect density, also in the case of a consistent number (30) of QW periods. The optical properties, characterised by excitonic features, show well resolved peaks ascribable to heavy and light hole to electron transitions, in good agreement with theory. The benefit role of the QW region was proved by an extension of the spectral response and a reduction of the reverse dark current. A main limitation to the conversion efficiency is discussed in terms of InGaP non-intentional impurity contamination. [Copyright &y& Elsevier]

Abstract: Highly epitaxial thin films of YBa2Cu3O y (YBCO) have been grown on silicon with a double buffer of Eu2CuO4(ECO)/Y-ZrO2(YSZ). The utilization of the ECO layer, which possesses a very stable 214-T'' structure and excellent compatibility with YBCO, greatly improves the epitaxy and surface morphology of the grown YBCO film, whereas the YSZ layer efficiently blocks the interaction between silicon substrate and YBCO. The grown films were characterized by grazing incidence X-ray reflection, rocking scans of the X-ray diffraction peaks, scanning electron microscopy, cross-sectional transmission electron microscopy, and surface profilometry. The results showed an enhanced crystallinity and very clear interfaces between layers, demonstrating the advantages of such an ECO/YSZ double buffer. It was also found that this bi-layer buffer structure could greatly improve the surface roughness of the YBCO films. [Copyright &y& Elsevier]

Abstract: Elemental in-depth analysis of the Y–Pd thin film under hydrogenation/dehydrogenation has been performed by Glow Discharge Optical Emission Spectroscopy (GDOES). This technique was able to detect qualitatively the changes in the composition of the layer, particularly the in-depth H and O distribution during hydrogen uptake and release. The charge of the film with hydrogen was done under electrochemically controlled conditions, while the discharge was effectuated in different modes: electrochemically, in alkali electrolyte (forced anodic discharge) or spontaneously, in air ambient or in the electrolyte (open potential circuit discharge). In-depth GDOES profiles of hydrogen at different times during the charge/discharge process confirm the processes of capture/release of hydrogen into the film corresponding to a reversible transition between the two hydrogenation states of yttrium: di- and tri-hydrides. The study of the oxygen profile reveals the presence of this element in the as prepared films and demonstrates its further accumulation under cyclic hydrogenation/dehydrogenation. Anodic discharge of the electrode rapidly increases oxygen content and probably leads to the formation of hydroxides along the whole yttrium depth with the consequent deterioration of the optical switching properties. [Copyright &y& Elsevier]

Abstract: In this work, we report evaluation of the atomic-scale phase transformation characteristics in one of the most comprehensively utilized phase change materials today, Ge2Sb2Te5 thin film. The phase transformation of Ge2Sb2Te5 thin film from amorphous to hexagonal structure via fcc structure was confirmed by XRD measurements. The approximate values of optical energy gap are 0.72 and 0.50 eV, with slopes (B1/2) in the extended absorption region of 5.3×105 and 10×105 cm−1∙eV−1 for the amorphous and fcc-crystalline structures, respectively. In addition, X-ray photoelectron spectroscopy analysis revealed strengthening of the Te–Te bond as well as weakening of the Ge–Te bond during the amorphous-to-crystalline transition. This trend was also observed in extended X-ray absorption fine structure analysis where the Ge metallic bond lengths in the amorphous, fcc, and hexagonal structures were 0.262, 0.280, and 0.290 nm. [Copyright &y& Elsevier]

Abstract: PDMS (polydimethylsiloxane) shadow masks were fabricated by replica molding using laser-patterned metal shadow masks as primary templates, which were applied to solution as well as vapor deposition to prepare patterned thin films on solid substrates. We demonstrated a method of fabricating cadmium sulfide (CdS) thin-film transistors (TFTs) using the prepared PDMS shadow masks thanks to their solution-tight, free-standing and elastic characteristics. The patterned CdS thin films were deposited by chemical solution deposition in aqueous solution and aluminum metal electrodes were deposited by thermal evaporation. The electrical characteristics of the CdS/SiO2/n-Si transistors consisted of a field effect mobility of ~0.5 cm2/Vs, a threshold voltage of ~14 V and an on/off ratio of ~107. [Copyright &y& Elsevier]

Abstract: Optical properties of nanocrystalline Nd-modified lead–zirconate–titanate thin films were studied. Pulsed laser deposition was used for thin-film fabrication at room temperature. Thin films were deposited on single-crystal MgO (100) substrates and post-annealed between temperatures 400 °C–1000 °C. The crystal structure and thin film morphology were studied using x-ray diffraction technique and atomic force microscopy, respectively. The optical transmission spectra of the films were measured at UV–vis–IR wavelengths and the results were utilized to obtain the refraction index n, extinction coefficient k, and the value of the band gap E g. Thin films annealed at different temperatures had a different crystal structure and morphology. Film thickness and annealing temperature also had an effect on the crystal orientation of the films. Trigonal and tetragonal phases co-existed in analyzed films so that films with thickness of 150 nm had strong tetragonal orientation with increasing post-annealing temperature. Trigonal and tetragonal phase co-existence was present in films with thickness of 300 nm post-annealed at low temperatures. Optical absorption edge shifted to shorter wavelengths with decreasing film thickness and post-annealing temperature which led to increase in band gap energies. Atomic force microscopy studies showed a clear dependence of films root mean square roughness on post-annealing temperature and crystal structure. [Copyright &y& Elsevier]

Abstract: La0.835Na0.165Mn0.9RE0.1O3 (RE Mg, Cr, Ti) films were prepared by chemical solution deposition method on LaAlO3 (100) substrates. All the as-grown thin films are highly (h00) oriented with pseudocubic structure. There is a transition from the paramagnetic to ferromagnetic state in all the samples, but the substitution of Mn3+ ions by Mg2+ ions appears spin-glass cluster in the low temperature. Additionally, the sample La0.835Na0.165Mn0.9Mg0.1O3 has the lowest Curie temperature and the metal-insulating transition temperature, and the resistivity is the highest. The resistivity curve exhibits insulating behavior in the temperature range of 100–390 K. The results are discussed in terms of the blocking of the percolative channel and the electric and magnetic disorder because of the substitution of a nonmagnetic ion. [Copyright &y& Elsevier]