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Due to their excellent hardness, transition metal nitrides have become a promising coating material for cutting tools and high-friction surfaces. The wear and corrosion protection offered by metal nitride hard coatings has paved the way for research on different combinations of metal nitrides. In this study, binary transition metal nitride coatings of CrMoN and CrTiN are deposited onto cutting tools and different substrates by co-sputtering of two metal targets simultaneously at an oblique angle by an ion-assisted DC magnetron sputtering process. The purpose of the deposition is to develop a uniform adhesive hard coating onto the specimens and to study their characteristics and performance. Both the hard adhesive coatings developed offer good surface morphologies which have been confirmed by AFM and FESEM, and their elemental composition is confirmed by XRD, XPS, and EDS characterizations. Hardness is measured by nanoindentation and also electrochemical studies for corrosion measurements are performed. In both the coatings, individual nitride phases have been formed in a mixed manner and have achieved a hardness value of about 13 GPa and the corrosion resistance of the coated specimen is found to be improved in comparison with the uncoated substrates. [ABSTRACT FROM AUTHOR]

The Ag-ZnO nanocomposite thin films of varying Ag contents were synthesized successfully using simultaneous RF- and DC-magnetron sputterings on quartz substrates. The as-prepared nanocomposites were then annealed in a mixture of hydrogen plus argon environment (95%Ar+5%H2) at a temperature of 300 °C. The pristine and annealed films were then subjected to synchrotron XRD to study for any possible structural modifications induced in the films. The crystalline behavior of the hexagonal wurtzite structure of ZnO, in the pristine and annealed samples of Ag-ZnO nanocomposites, was evident in samples prepared at low Ag content, but with increasing Ag content, the crystalline behavior of the hexagonal wurtzite structure was suppressed. FESEM utilized to study the formation of nanoparticles in the films revealed the non-uniform distribution and agglomeration of nanoparticles increases as the Ag content increases. A broad surface plasmon region in the range of 380–450 nm was observed for different compositions with remarkable blue and red shifts using UV-visible spectroscopy. These high-quality Ag-ZnO nanocomposite thin films with tunable optical properties were then used as surface-enhanced Raman spectroscopy (SERS) substrates for the detection of rhodamine B (RhB) at low concentrations of 10−6 M. The detection of RhB in trace amounts is important in the current scenario as wastewater discharge is a serious threat to our ecosystem. [ABSTRACT FROM AUTHOR]

Several techniques have been developed to confer antibacterial properties to cotton textiles using silver nanoparticles. However, the antimicrobial performance of such a modified fabric can drastically decrease after a washing treatment. The aim of this work has been to develop antibacterial composite coatings with improved water resistance, deposited on cotton via the co-sputtering technique. The thin coatings, composed of a silica, alumina or zirconia matrix, with well embedded silver nanoclusters, were made to homogenously cover the cotton threads. The amount of silver was modulated, as was the power applied to the target, that is, 3 W for a lower amount and 5 W for a larger amount. The release of silver ions from the coatings into distilled water was very low, even after 14 days (less than 1 ppm) for all the coatings. The coated and uncoated cotton textiles were directly infected with the textile-colonizing pathogens Escherichia coli and Pseudomonas aeruginosa. After 24 h, a count of the colony forming units (CFU) revealed that the textiles coated with either the silver nanocluster/silica or zirconia matrix coatings were effective in preventing the adhesion and proliferation of E. coli bacteria, thereby preserving the textiles from contamination. However, P. aeruginosa was only absent in the case of the silica coatings or when the zirconia and alumina matrix coatings contained a large amount of silver. In all the considered cases, the CFU number was reduced with respect to the uncoated textiles. The durability of all the coatings was verified after ten washing cycles. Finally, coated textiles reported to be cytocompatible towards human fibroblasts and keratinocytes after simulating the release of toxic compounds or by directly seeding cells onto materials' surface. [ABSTRACT FROM AUTHOR]

Due to their outstanding power density, long cycle life and low cost, supercapacitors have gained much interest. As for supercapacitor electrodes, molybdenum nitrides show promising potential. Molybdenum nitrides, however, are mainly prepared as nanopowders via a chemical route and require binders for the manufacture of electrodes. Such electrodes can impair the performance of supercapacitors. Herein, binder-free chromium (Cr)-doped molybdenum nitride (Mo2N) TFEs having different Cr concentrations are prepared via a reactive co-sputtering technique. The Cr-doped Mo2N films prepared have a cubic phase structure of γ-Mo2N with a minor shift in the (111) plane. While un-doped Mo2N films exhibit a spherical morphology, Cr-doped Mo2N films demonstrate a clear pyramid-like surface morphology. The developed Cr-doped Mo2N films contain 0–7.9 at.% of Cr in Mo2N lattice. A supercapacitor using a Cr-doped Mo2N electrode having the highest concentration of Cr reveals maximum areal capacity of 2780 mC/cm2, which is much higher than that of an un-doped Mo2N electrode (110 mC/cm2). Furthermore, the Cr-doped Mo2N electrode demonstrates excellent cycling stability, achieving ~ 94.6% capacity retention for about 2000 cycles. The reactive co-sputtering proves to be a suitable technique for fabrication of binder-free TFEs for high-performance energy storage device applications. [ABSTRACT FROM AUTHOR]

Sn-Si composite anodes with linear variation composition could be synthesized by co-sputtering method directly. Ductile Sn was used as an additive material for improving the capacity and electrical conductivity of the brittle Si since the synergetic effect. The deposited films possessed a unique phase-separated structure and is beneficial to buffer the volume expansion introduced by an alloying/dealloying process, and the distributed Sn particles improved the transportation of Li+ and remedy the inherent poor conductivity of Si. As a result, the optimal Sn-Si composite film (Sn:Si = 35.9:64.1) possessed a stable discharge capacity of 1134.0 mAh/g after two cycles and a high-capacity retention of 82.8% after 50 cycles. Si played an important role as a buffer matrix, and the increased Si content could suppress the growth of Sn grains, reduce the structural damage and enhance film adhesion. The obtained Sn-Si component film was one strong candidate for next-generation thin film anode. [ABSTRACT FROM AUTHOR]

A systematic study of the effect of Al2O3 doping concentration in targets on the structure and optoelectronic characteristics of sputtered MgZnO films was conducted. The films were prepared on glass substrates by radio frequency magnetron sputtering from a MgZnO target mixed with 0–4 wt.% Al2O3. X-ray diffraction analysis demonstrated that the Al-doped MgZnO films had a highly (002) preferred orientation with only one intense diffraction peak. The electrical properties of the Al-doped MgZnO films were dependent on the Al2O3 concentration. Optimal results of Al-doped MgZnO films were obtained at an Al2O3-doping concentration of 2 wt.%, with low resistivity of 2.82 × 10−3 Ω-cm and high transmittance of 91% in the visible region. Outstanding electrical properties were achieved because of the significantly increased carrier concentration. The optical bandgap of the Al-doped MgZnO films showed a short-wavelength shift with increased Al2O3-doping concentration. The low electrical resistivity and high transparency of Al-doped MgZnO films indicated their potential as transparent conductive oxide window materials for UV optoelectronic devices. [ABSTRACT FROM AUTHOR]

W–C thin films were prepared by non-reactive magnetron co-sputtering simultaneously from pure tungsten and carbon targets in an argon atmosphere at room temperature on Si(100) substrate. The main purpose of the present work was to investigate the influence of deposition method and annealing process on structural and electrical properties of the tungsten carbide thin films. The experimental results show that the growth rate of films was about 5.46 nm/min; the films have spherical granular structure. Hexagonal W2C appeared when the annealing temperature was 700 and 800°C and W : C atomic ratio of 1.18. Moreover, grain size of W2C films was about 8.1 and 11.7 nm after annealing at 700 and 800°C, respectively. Resistivity of films was relatively high, possibly due to the presence of excess carbon in the films not bound with tungsten, verified by the Raman spectrum. [ABSTRACT FROM AUTHOR]

In this study, various indium zinc tin oxide (IZTO) films were fabricated using co-sputtering to explore amorphous transparent conducting oxides as alternatives to crystalline indium tin oxide (ITO). Various Zn ratios were tuned to study their effects on the structural evolution of IZTO. Amorphous IZTO (aIZTO) films were obtained when the Zn concentration was higher than approximately 17 at.%. X-ray diffraction and transmission electron microscopy analyses indicated that amorphous structures were formed due to the high crystallization temperatures of IZTO and nanocrystalline In2Zn5O8, which also caused aIZTO to exhibit small band gaps. On average, 87% transmittance was achieved in the visible light range. The aIZTO films had substantially higher transmittance in the infrared region than the ITO films did. Samples with Zn ratios between approximately 17 at.% and 27 at.% exhibited resistivity (approximately 3 × 10−4 Ω-cm), mobility (7 cm2 V−1 s−1), and carrier concentrations (4 × 1021 cm−3) comparable to those of crystalline ITO. Thus, the aIZTO films are promising alternative TCO materials. The mechanisms of competition between the crystallinity, oxygen deficiency, high-mobility In2Zn5O8, and electron and hole generation rates were applied to shed light on the excellent electrical and transport properties of aIZTO films. [ABSTRACT FROM AUTHOR]

Silver (Ag), palladium (Pd), and bimetallic silver-palladium (Ag-Pd) coatings were deposited on a mild steel surface by the co-sputtering method. The aim was to investigate and compare the corrosion behavior of Ag-Pd nano-coatings as well as the effect of increasing the weight ratio of Ag in the Ag-Pd alloy in the 3.5% NaCl solution. The corrosion protection performance and barrier protection properties were monitored using electrochemical impedance spectroscopy and potentiodynamic polarization. The surface of the coatings was characterized by scanning electron microscopy, atomic force microscopy, energy-dispersive x-ray spectroscopy, and field-emission scanning electron microscopy. The results of corrosion measurements revealed a relationship between silver wt.% and corrosion resistance. Also, all the coatings had protective effects and barrier properties on the mild steel in the corrosive solution. The best efficiency was observed in silver monometallic coating with 54 nm thickness. [ABSTRACT FROM AUTHOR]

This work addresses the role of excess Al and deposition rate in reducing the doping efficiency of Al+3 cations in Al-doped ZnO (AZO) films. In this regard, AZO films were deposited on the soda lime glass substrates using co-sputtering from ceramic AZO/ZnO and metallic Al targets. Whereas power to ZnO/AZO target was kept constant, power to Al target was varied to see the effect of varying Al concentration (and deposition rate) on its doping efficiency. Here, Al doping efficiency in ZnO is found to increase initially with increasing deposition rate and Al content, beyond which it decreased because of the formation of higher AlxOy in combination with increased trapped Al in the amorphous regions of these films. Moreover, a detailed discussion on the mechanism of the deposition rate and thereby induced variation in Al doping efficiency is discussed and then related to the optoelectronic properties of these films. [ABSTRACT FROM AUTHOR]

Bi2Te3-based materials have been widely utilized for commercial bulk thermoelectric (TE) devices. For the manufacture of miniaturized TE devices, the large-scale deposition of high-performance Bi2Te3-based thin films is crucial. However, it has not yet been effectively resolved. Herein, the Bi0.5Sb1.5Te3 films with different thicknesses were grown on sapphire substrates by controlling the co-sputtering time. We reveal that the film thickness has a significant impact on the electrical transport properties. Due to the mutual influence of electrical conductivity and Seebeck coefficient, there exists an optimal thickness with the maximum power factor is as high as 2900 μW m−1 K−2. Therefore, systematic research on the thickness-dependent TE characteristics of Bi2Te3-based films and the deposition of high-performance films will provide important information for the large-scale development of high-performance micro-TE devices. [ABSTRACT FROM AUTHOR]

In this study, new barrier-free Cu(NbC) alloy films with two different thicknesses, i.e., 8 and 300 nm, containing 0.3 at% C and 0.5 at% Nb, which are deposited via co-sputtering on three types of substrates, viz., Si, stainless steel and polyimide (PI), have been developed, annealed, measured and analysed. The resistivity value of the new 300-nm-thick films atop Si substrates is 3.07 μ Ω cm after annealing at 450 ∘ C for 200 h. The low resistivity and diffusion depth of the new films exhibit their good quality in anti-oxidation stability in a high-temperature environment. The films also display high-adhesive strength atop either stainless-steel or PI substrates, ∼ 7–8 times greater than that of their pure-Cu counterparts. In sharp contrast, the antibacterial ratio of the new films is ∼ 96 % while that of their pure-Cu counterparts is 0%. In addition, the contact angles of Cu(NbC) films are greater than those of their pure-Cu counterparts, resulting in a far superior antibacterial efficacy for the new films to pure-Cu films against, for example, Staphylococcusaureus BCRC 10451. With these desirable merits, the new films seem to be a good candidate material for bacteria killing and prevention, reduction of legionella spread inside hospitals and / or large buildings, biological medical care systems and advanced surgical tools. The new films deposited on PI substrates also seem to be suitable for making supple electrically conductive parts or devices, such as flexible panels, keyboards, screens, smartphones embedded in smart textiles and so forth. [ABSTRACT FROM AUTHOR]

A sneak path current—a current passing through a neighboring memory cell—is an inherent and inevitable problem in a crossbar array consisting of memristor memory cells. This serious problem can be alleviated by serially connecting the selector device to each memristor cell. Among the various types of selector device concepts, the diffusive selector has garnered considerable attention because of its excellent performance. This selector features volatile threshold switching (TS) using the dynamics of active metals such as Ag or Cu, which act as an electrode or dopant in the solid electrolyte. In this study, a diffusive selector based on Ag-doped HfOx is fabricated using a co-sputtering system. As the Ag concentration in the HfOx layer varies, different electrical properties and thereby TS characteristics are observed. The necessity of the electroforming (EF) process for the TS characteristic is determined by the proper Ag concentration in the HfOx layer. This difference in the EF process can significantly affect the parameters of the TS characteristics. Therefore, an optimized doping condition is required for a diffusive selector to attain excellent selector device behavior and avoid an EF process that can eventually degrade device performance. [ABSTRACT FROM AUTHOR]

In this report, Bi-doped antimony zinc thin films were prepared on BK7 glass substrates by using direct magnetron co-sputtering technique. Bi was doped at the halfway point of deposition, and the doping contents were 2 at.%, 4 at.%, and 6 at.%, respectively. We present the micro-structural and room-temperature thermoelectric properties of Bi-doped Zn-Sb thin films in this paper. The maximum value of the Seebeck coefficient was found to be 300 μV/K with a Bi content of 6 at.%. This is one of the highest values of the Seebeck coefficient for Zn-Sb thin films deposited by direct magnetron co-sputtering. Carrier concentration is obtained from Hall effect measurements, which provided insights into the transport mechanisms that affected electrical conductivity and Seebeck coefficient. It is significant to doping Bi, which enhances the power factor to an optimal value of 0. 26 mW/mK and the optimal ZT value to 0.086 with the Bi content of 4 at.% at room-temperature. [ABSTRACT FROM AUTHOR]

In this work, CuInGa alloy precursor films are fabricated by co-sputtering of CuIn and CuGa targets simultaneously. After selenization in a tube-type rapid thermal annealing system under a Se atmosphere, the Cu(In, Ga)Se (CIGS) absorber layers are obtained. Standard soda lime glass (SLG)/Mo/CIGS/CdS/i-ZnO/ITO/Ag grid structural solar cells are fabricated based on the selenized CIGS absorbers. The influences of selenization temperatures on the composition, crystallinity, and device performances are systematically investigated by x-ray energy dispersive spectroscopy, x-ray diffraction, Raman spectroscopy, and the current density-voltage ( J- V) measurement. It is found that the elemental ratio of Cu/(In + Ga) strongly depends on the selenization temperatures. Because of the appropriate elemental ratio, a 9.92% conversion efficiency is reached for the CIGS absorber selenized at 560°C. After the additional optimization by pre-annealing treatment at 280°C before the selenization, a highest conversion efficiency of 11.19% with a open-circuit ( V ) of 456 mV, a short-circuit ( J ) of 40.357 mA/cm and a fill factor of 60.82% without antireflection coating has been achieved. Above 13% efficiency improvement was achievable. Our experimental findings presented in this work demonstrate that the post-selenization of co-sputtered CuIn and CuGa precursor is a promising way to fabricate high quality CIGS absorbers. [ABSTRACT FROM AUTHOR]

Porous Si-Al films were fabricated by magnetron sputtering (co-sputtering) using three different copper substrates as current collectors, respectively. The morphology, compositions, structure, and crystallinity of the porous Si-Al films anodes were examined by using SEM, EDX, TEM, XRD, and Raman spectroscopy. The electrochemical properties of the porous Si-Al films anodes were evaluated by galvanostatic cycling. The Si-Al film deposited on copper foam showed higher insertion/extraction capacity, capacity retention, and longer cycle life in comparison to the Si-Al films deposited on expanded copper mesh and even copper mesh grid, which could be attributed to its unique three-dimensional macroporous structure. The three-dimensional macroporous structure could offer larger materials/electrolyte contact area, a much better adhesion, lower electrical resistance (i.e., well conductive), and stress-alleviated environment to partly accommodate volume expansion that leads to exfoliation during cycling. [ABSTRACT FROM AUTHOR]

In the present study, p-type Bi xSb 2−xTe 3 thermoelectric thin films with various chemical compositions were fabricated by a magnetron co-sputtering process. The influence of Bi content ( x) on the microstructures and thermoelectric properties of Bi xSb 2−xTe 3 films was investigated. It was found that the grain size of nanocrystalline Bi xSb 2−xTe 3 films decreased when increasing the Bi content from x = 0 to x = 0.57, which resulted in a concurrent decrease in the carrier mobility. Similarly, carrier concentration decreased with increasing Bi content, which caused an increase in the Seebeck coefficient. The largest room-temperature power factor reached 31.3 µWK −2cm −1 for the film with x = 0.45. [ABSTRACT FROM AUTHOR]

Multilayer coatings of titanium/ titanium silicon oxynitride (Ti/TiSiNO) were fabricated on stainless steel 434-L substrates by sputtering technique using Ti and TiSiO targets. The multilayers were formed by alternately and simultaneously introducing and suspending a 4-sccm flow of nitrogen together with an interchange of targets, during different time periods of 1.0, 2.0, 3.0 and 4.0 min; thus, we obtained intervals of different thickness by alternating the target (Ti) and using only argon, and later with both targets (Ti + TiSiO) and the two gases (Ar + N). The final thickness was within a range of 0.4-0.8 μm, depending on the number of multi layers obtained by means of glow discharge optical emission spectroscopy. The structure, topography, color, durability and nanofriction were analyzed in accordance with the growth parameters used. It was found that the values of hardness depend on the number of layers deposited. The greatest number of layers, 48 of them, was obtained with a time period of 1 min, thereby attaining the maximum value of hardness and the minimum value for both the friction coefficient and the RMS, with 31 GPa, 7.42 × 10 and 0.17 nm, respectively. The phases found correspond to TiN, SiN, rutile phase of TiO and Ti. The TiO phase was corroborated with Raman dispersion spectroscopy. The color of the coatings was affected by variation in the working pressure, which varied because of the internal process of reactive sputtering. [ABSTRACT FROM AUTHOR]

The present paper deals with deposition of titanium and zirconium oxynitride films prepared from co-sputtering titanium and zirconium targets by reactive RF magnetron sputtering. The effect of power variation on various properties of the deposited films is analysed. The film gets transformed from amorphous to well crystalline oxynitride films with gradual increase of target powers as observed from XRD graphs. The films exhibit hydrophilic and hydrophobic behaviours depending upon the presence of various phases. Surface energy decreases as the film properties change from hydrophilic to hydrophobic due to greater contact angle values. The optical properties were measured by UV-Vis-NIR spectrophotometer, transmission spectra and bandgap values show variation with respect to change in elemental composition as determined from EDS analysis. [ABSTRACT FROM AUTHOR]

In this work, thin films deposited by pulsed DC magnetron sputtering of [Ti-Al/Ti-Al-N] and [Ti-Cr/Ti-Cr-N] multilayers of nanometric periods were analyzed by AFM in contact mode to measure values of lateral and normal forces. From these measurements, the coefficient of friction (COF) of these materials in contact with the AFM tip was calculated. Measurements were made with three types of silicon tips, diamond-coated, Pt-Cr-coated, and bare silicon. Significant differences between the tip materials in contact with the samples, which affected the COF, were observed. The effect of the environmental layer of water covering the surface sample and the tip appears as the most important factor affecting the tribology behavior of the tip-sample contact. For diamond-coated and bare silicon tips there is an additional adherence force increasing the normal load. But for tips platinum-chromium-coated there is a repulsive force due to this water layer, which behaves as a lubricant layer before a threshold load. [ABSTRACT FROM AUTHOR]

We describe a dedicated co-sputtering/ion-mill system developed to study metallic paramagnetic films for use in magnetic microcalorimetry. Small-diameter sputtering guns allow study of several precious-metal paramagnetic alloy systems within a reasonable budget. We demonstrated safe operation of a 1″ sputtering gun at greater than five times the rated maximum power, achieving deposition rates up to ∼ 900 Å/min/gun (Cu) in our co-sputtering geometry. Demonstrated co-sputtering deposition ratios up to 100:1 allow accurate tuning of magnetic dopant concentration and eliminate the difficulty of preparing homogeneous alloy targets of extreme dilution. [ABSTRACT FROM AUTHOR]

GdO doped HfO (GDH) films were grown on p-type Si (001) substrates by radio frequency co-sputtering. The amorphous GDH high k film as grown and annealed at 700 °C was determined by reflection high-energy electron diffraction (RHEED) and high resolution transmission electron microscopy (HRTEM). X-ray photoelectron spectroscopy (XPS) results indicate that the doping content of GdO is 10% in a mole ratio, and gadolinium silicate is formated between GDH film and Si substrates. Hf4f and O1s peaks shift to lower and higher binding energy, respectively. A leakage current density of 1.3 × 10 A/cm at −1 V, a hysteresis voltage of 40 mV, a dielectric constant of 21.3 and a CET of 1 nm are obtained from a capacitor with Pt/GDH/Si/Ag stack through capacitance-voltage ( C-V) and current-voltage ( I-V) measurements. [ABSTRACT FROM AUTHOR]

In this study we have used a combinatorial approach for producing binary and ternary alloy thin film libraries using a lab-scale RF co-sputtering system. Initially we used two elemental sputtering targets, i.e. aluminum (Al) target and neodymium (Nd) target, to produce a film library of varying composition and successfully identified a suitable composition range (1.95–2.38 at% Nd) in which resistance to hillock formation and resistivity of the film spots were found to be satisfactory in annealed state (350°C, 30 min). In another case, in order to form ternary alloy composition library we have used two sputtering targets, i.e. an Al-0.5 at% Nd alloy target and an elemental Ni target. Though, co-sputtered Al-0.6 at% Nd-0.9 at% Ni alloy films showed satisfactory resistance to hillock formation and low resistivity after annealing, film deposited from a ternary alloy target with the same composition failed to show satisfactory resistance to hillock formation during annealing. In case of Al-0.6 at% Nd-0.9 at% Ni alloy target, 250 nm thick film showed poor resistance to hillock formation than the 500 nm thick film. This clearly showed thickness-dependent hillock performance of Al-0.6 at% Nd-0.9 at% Ni alloy. In this study it was found that, in addition to the process variables, metallurgical microstructure of the alloy sputtering targets had significant effect on the film properties which was not obvious from the results of films deposited using co-sputtering of the individual elemental targets. [ABSTRACT FROM AUTHOR]

In−Zn−Sn−O films were deposited on a polycarbonate (PC) substrate by a magnetron co-sputtering system using two cathodes (DC, RF) without substrate heating. Two types of ITO targets (target A: doped with 5 wt.% SnO2, target B: doped with 10 wt.% SnO2) were used as an In−Sn−O source. The ITO and ZnO targets were sputtered by DC and RF discharges, respectively, and the composition of the In−Zn−Sn−O films was controlled via the power ratio of each cathode. In the case of ITO target A, the lowest resistivity (4.3×10−4 Ωcm) was obtained for the film deposited at the RF power (ZnO) of 55W. In the case of ITO target B, the lowest resistivity (2.9×10−4 Ωcm) of the film was obtained at the RF power (ZnO) of 30W, which was attributed to the increase in carrier density. Hall mobility decreased with increasing carrier density, which could be explained by the increase in ionized impurity scattering. [ABSTRACT FROM AUTHOR]

Composite dielectric thin films of various combinations of AlO and TiO were deposited by e-beam evaporation and co-sputtering. Composition control and dielectric properties are found to be superior for the co-sputtered films. A composition near 55 mole percent TiO gives optimum dielectric properties, dielectric constant of 40 and dissipation near .01. [ABSTRACT FROM AUTHOR]

Aluminum-doped zinc oxide (AZO) was cosputtered from ZnO and Al targets on glass substrates at room temperature. The effect of Al-target power and annealing atmosphere on structural and optoelectronic properties of AZO films was investigated.[Al]/[Zn] ratio increased to 0.258 when the Al-target power increased to 250 W. At a fixed Al-target power of 200 W, the [Al]/[Zn] ratio was 0.104 and the as-deposited AZO film demonstrated a low resistivity of 3.19 × 10−4 Ω-cm and high transmittance of approximately 90% in the visible region. After annealing at 500 °C in forming gas (5% H2 in Ar) atmosphere, the resistivity of the AZO film can be further reduced to 9.38 × 10−5 Ω-cm. Given its low-temperature process and good optoelectronic properties, sputtered AZO films that use ZnO and Al targets have high potential in various optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this study, we develop a facile method to fabricate highly sensitive and stable surface-enhanced Raman scattering (SERS) substrate, which is realized by combining co-sputtering with atomic layer deposition technology. To accomplish the SERS substrate preparation, we firstly utilized co-sputtering silver and aluminum on glass slides to form uniform discontinuous Ag film by removing Al later, which acted as SERS active moiety and presented high sensitivity in glycerin detection. After coating an ultrathin TiO2 layer via atomic layer deposition (ALD), the samples could further enhance the Raman signal due to the chemical effect as well as the long-range effect of the enhanced electromagnetic field generated by the encapsulated Ag nanoparticles (NPs). Besides, the coated sample could maintain the significant enhancement in air condition for more than 30 days. The high stability is induced by TiO2 layer, which efficiently prevents Ag NPs from surface oxidation. This highly sensitive and stable SERS substrate might highlight the application of interface state investigation for exploring novel liquid lubricating materials. [ABSTRACT FROM AUTHOR]