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Investigates the formation of cobalt-silicon films by the reaction of ternary cobalt/titanium/silicon system. Sequential deposition of cobalt films deposited on silicon substrates by ion beam sputtering; Success of the deposition in the growth of epitaxial single-crystalline cobalt-silicon films on both silicon and silicon substrates; Formation of thin layer of titanium-nitrogen on top of the epitaxial cobalt-silicon.

Presents a study which investigated the electrical transport properties of CoSi[sub2] and Co(Si[subx]Ge[sub1-x])2 films formed by different methods. Properties of the thin films after low temperature annealing; Discussion on the hole carrier density of the samples studied; Characteristic of CoSi[sub2] which made it a desirable material for contact and gate level interconnection of large scale integrated circuits.

Examines the Hall effect data of the bismuth-strontium-calcium-copper-oxygen thin films samples. Information on the thin film samples; Methodology of the study; Results and discussion.

Presents a study which measured the electrical resistivity and Hall effect of TiSi[sub2] thin films. Materials and methods used; Description of the temperature dependence of resistivity of TiSi[sub2] thin film; Overview of the Hall effect of TiSi[sub2] thin film formed on single crystal silicon.

Several ZnO:Al thin films have been successfully deposited on glass substrates at different substrate temperatures by RF (radio frequency) magnetron sputtering method. Effects of the substrate temperatures on the optical and electrical properties of these ZnO:Al thin films were investigated. The UV–VIS–NIR spectra of the ZnO:Al thin films revealed that the average optical transmittances in the visible range are very high, up to 88%. X-ray diffraction results showed that crystallization of these films was improved at higher substrate temperature. The band gaps of ZnO:Al thin films deposited at 25 ℃, 150 ℃, 200 ℃, and 250 ℃ are 3.59 eV, 3.55 eV, 3.53 eV, and 3.48 eV, respectively. The Hall-effect measurement demonstrated that the electrical resistivity of the films decreased with the increase of the substrate temperature and the electrical resistivity reached 1.990×10 −3 Ω cm at 250 ℃. [ABSTRACT FROM AUTHOR]

AlSb films which are a promising absorber layer for thin film solar cells were grown on glass substrate at different substrate temperature ranging from room temperature to 400 °C on glass substrates using aluminum-antimony alloying target by pulsed laser deposition (PLD) technique. Structural, optical and electrical properties of AlSb thin films were studied by X-ray diffraction (XRD), ultraviolet–visible spectrophotometer and a home-made four-probe-contact high temperature system respectively. XRD pattern shows that AlSb film is amorphous at room temperature, but when substrate temperature is higher than 100 °C, AlSb films present cubic phase structure with the preferential orientation of (111) plane. And intensity of diffraction peaks of AlSb film prepared at substrate temperature of 200 °C are stronger than that of other substrate temperature. The electrical measurement results show that conductivity activation energy of AlSb film is 0.25 eV and 0.28 eV. The indirect optical band gap is about 1.63 eV, which is very close to its theoretical value of 1.62 eV. The results of energy dispersive spectrometer (EDS) indicated the ratio of Al to Sb of AlSb films is about 1:1. [ABSTRACT FROM AUTHOR]

Aluminum antimony (AlSb) is a potential absorber for solar cells. In present work, we fabricated AlSb thin films by using pulsed laser deposition method, and investigated the influence of substrate temperature on the structural, electrical and optical properties of AlSb thin films. The results suggested that the AlSb thin films were crystal when the substrate temperature was higher than 300 °C. The average grain size of AlSb films increased and the electrical resistivity decreased with the increase of substrate temperature. At the optimized temperature of 400 °C, the optical band gap of AlSb thin film was 1.82eV. The simulated device performance of ZnS/AlSb ultra-thin solar cells showed that the power conversion efficiency was 18.01% and the quantum efficiency values were higher than 55% in the visible range. [ABSTRACT FROM AUTHOR]

Ba(Nb x Sn 1- x )O 3 (BNSO) films were epitaxially grown on (001) oriented MgO substrates with Nb doping content from 0.00 to 0.15 by pulsed laser deposition. The structural, electrical, and optical properties of the films were investigated in detail by x-ray diffraction, x-ray photoelectron spectroscopy, Hall effect and transmittance spectroscopy. The lowest room temperature resistivity value of 4.81 × 10 −4 Ω cm with carrier concentration and mobility of 6.59 × 10 20 /cm 3 and 19.65 cm 2 /V was observed in the film at x = 0.05, indicating an excellent electrical conductivity. All the BNSO films exhibit a high transmittance of more than 80% in the visible range. The variation of band gap E g with Nb doping content was interpreted by the Burstein-Moss effect and the occurrence of octahedral tilt distorting. Excellent optical and electrical properties suggest that BNSO films have potential applications in the optoelectronic devices as transparent and conducting oxide material. [ABSTRACT FROM AUTHOR]

The relatively poor selectivity of electrospun nanofiber membrane (ENM) substrate supported thin film composite forward osmosis (eTFC-FO) membranes has hindered their applications. In this study, to overcome the high roughness and large pore size of ENM substrate, a smooth and hydrophilic polydopamine (PDA) interlayer was fabricated on a polyvinylidene fluoride (PVDF) ENM, which was found to be favourable for the formation of a thinner, more cross-linked and less defective polyamide (PA) active layer on the ENM substrate. Desalination tests proved the great effectiveness of PDA interlayer on performance improvement for the eTFC-FO membrane. A quite high water flux (43.0 LMH) and ions rejection (>97.0%) were achieved for a real desulfurization wastewater desalination tested in FO mode. The alleviated PA defects by the PDA interlayer could greatly improve the selectivity. As a comparison with PDA interlayer, PDA coating on each individual nanofiber inside the PVDF ENM substrate was also prepared for eTFC-FO membrane, which would not overcome the disadvantages of rough and large pore sized ENM substrate for PA preparation. Mechanisms of PA formation and performance improvement were detailly discussed in this work. [Display omitted] • Polydopamine (PDA) interlayer was prepared on rough & hydrophobic PVDF nanofibers. • PDA interlayer facilitates the formation of thinner and more cross-linked PA layer. • Interlayer can alleviate PA defect and improve selectivity of eTFC-FO membrane. • eTFC-FO with interlayer enhanced performance for high salinity water desalination. [ABSTRACT FROM AUTHOR]

Abstract: The high-quality La0.7Ba0.3MnO3 (LBMO) epitaxial films were deposited on (001) oriented LaAlO3 (LAO) substrates by magnetron sputtering technique. The low temperature electrical transport behavior of the films was investigated in details. In the low temperature ferromagnetic metallic state, a common feature, i.e., the minimum of electrical resistivity, was found in both of the films post annealed in oxygen and argon atmosphere. By taking the unusual combination of factors including spin dependent Kondo-like scattering, electron–electron and electron–phonon interactions into account, the resistivity minimum can be fitted well. It was found that the spin dependent Kondo-like scattering plays an important role in both the films, indicating the intrinsic spin disorder in strongly correlated manganites. Furthermore, in a lower temperature interval 4–25K, a stronger electron–electron interaction was observed in the Ar annealed films, which can be attributed to the enhanced disorder arising from oxygen vacancy. [Copyright &y& Elsevier]

Abstract: Graphene–carbon nanotube (CNT) hybrid materials were synthesized by simple one-step chemical vapor deposition (CVD) using ethanol as precursor. On a copper foil decorated with silicon nanparticles (Si NPs), a graphene film grows uniformly on the substrate while CNTs sprout out from Si NPs to form a network on top. The density of CNTs can be controlled by the CVD growth temperature. As measured by scanning and transmission electron microscopy, the obtained CNTs exhibit bamboo-like multiple-wall structures. Electrical characterization shows that the graphene–CNT hybrids exhibit p-type field-effect characteristics and a significantly higher conductivity compared to a CVD grown pure graphene film. [Copyright &y& Elsevier]

Abstract: The magnetic and transport properties of epitaxial La0.7Ba0.3MnO3 films on LaAlO3 substrates have been investigated and compared with those on SrTiO3 substrates. It is found that the ferromagnetic and metallic transition temperature of the highly compressive strained films on LaAlO3 substrates decreases steadily with decreasing film thickness, while it changes little in the lightly strained films on SrTiO3 substrates. The properties of the films on LaAlO3 substrates are more sensitive to a post-annealing procedure. A tendency to phase separation, which induces a difference between the insulator–metal transition temperature T MI and the Curie temperature T C, is observed for the films with a medium oxygen annealing process. We argue that the phase separation is due to both the highly compressive strain and oxygen deficiency in the films. [ABSTRACT FROM AUTHOR]

Abstract: A facile approach to the formation of Ag/PPy composite film, through the reaction of Ag+ and pyrrole monomer, was developed with the help of synergistic effect of NH3·H2O on this reaction. Black or gray Ag/PPy film precipitated on the insert wall of the vessel within 0.5h with this new method. The Ag/PPy composite film has good conductivity (sheet resistance: 0.28Ω/square) and superhydrophility (contact angle of water, CAW ∼0°). Mechanism involved in the reaction rate acceleration was briefly discussed. [Copyright &y& Elsevier]

Flexible thin-film solar cells are important for their advantages in many aspects, and aluminum antimonide (AlSb) can be used as an absorbent layer in thin-film solar cells. However, its deliquescence limits its practical use. In this work, AlSb films were prepared by radio frequency (RF) magnetron sputtering on stainless steel flexible substrates. A flexible conformal coating membrane using acrylic resin was deposited on the AlSb films and its deliquescence prevention effect was verified. It was found that after conformal coating treatment, the deliquescence of the AlSb film was effectively stopped. The bare AlSb films and the Ni/AlSb/acrylic resin/Ni multilayer films were exposed to ambient air at the same time under the same conditions for lengths of time ranging from 1 min to 60 days. After 60 days, the bare AlSb film experienced significant deliquescence, such that the film was completely destroyed. However, the Ni/AlSb/acrylic resin/Ni multilayer films did not exhibit deliquescence. [ABSTRACT FROM AUTHOR]

Sb 2 Se 3 is a promising absorber for thin film solar cells due to its nontoxicity, low cost, earth abundance and excellent photovoltaic properties. However, few reports focus on Sb 2 Se 3 thin films prepared by pulsed laser deposition (PLD). Here we successfully deposited Sb 2 Se 3 thin films at different substrate temperatures by PLD. Structural, morphological, compositional, optical and electrical properties of Sb 2 Se 3 thin films were characterized. Results show that Sb 2 Se 3 thin films exhibit orthorhombic phase with good crystallinity and higher substrate temperature can distinctly improve crystal quality. Optical band gap is about 1.30 eV, 1.20 eV, 1.18 eV and 1.16 eV for Sb 2 Se 3 thin films deposited at 370 °C, 390 °C, 410 °C and 430 °C, respectively. In addition, the atomic ratio of selenium to antimony is 3/2, entirely consistent with the stoichiometry ratio of Sb 2 Se 3. Image 1 • Sb 2 Se 3 thin films were prepared on glass at different substrate temperatures by KrF PLD. • The atomic ratio of selenium to antimony was 3/2, entirely consistent with the stoichiometry ratio of Sb 2 Se 3. • Optical band gap was estimated to be 1.30 eV, 1.20 eV, 1.18 eV and 1.16 eV for Sb 2 Se 3 thin films deposited at 370 °C, 390 °C, 410 °C and 430 °C respectively. • High substrate temperature improved crystal quality. [ABSTRACT FROM AUTHOR]

Sb 2 Se 3 , an emerging promising binary compound semiconductor, was prepared at different substrate temperatures by pulsed laser deposition for thin film solar cells for the first time. In this work, CdS and Sb 2 Se 3 films were subsequently deposited by pulsed laser deposition to simplify the process. Film properties and device performance, closely related to the substrate temperature, were characterized by thermal gravimetric analysis, X-ray diffraction, UV–Vis–NIR spectrophotometer, scanning electron microscope, light and dark current density-voltage, external quantum efficiency and capacitance-voltage, respectively. Results indicate that Sb 2 Se 3 solar cells film deposited at 500 °C is better, with a better efficiency of 3.58%. Furthermore, SnO 2 high resistive layer was introduced into Sb 2 Se 3 solar cell to improve the junction quality, leading to a champion device efficiency of 4.41%. Image 1 • CdS/Sb 2 Se 3 bilayer was deposited by pulsed laser deposition for the first time. • Effects of substrate temperature on film properties and device performance were studied. • Sb 2 Se 3 film deposited at 500 °C is more suitable for Sb 2 Se 3 solar cells. • Champion efficiency of 4.41% was achieved due to the insertion of SnO 2 layer. [ABSTRACT FROM AUTHOR]

Sb 2 Se 3 , a very promising absorber layer for thin film solar cells, has attracted more and more attention because of its special structural and optical properties. In this work, pulsed laser deposition (PLD), a simple and effective technique, was used to deposit CdS/Sb 2 Se 3 solar cells for the first time. Results show that the grain size is 200–250 nm, the bandgap is calculated to be 1.21 eV and Sb 2 Se 3 thin film with thickness of 400 nm is more suitable for solar cells. To reduce reflection loss, lattice mismatch and shunt pathways, SnO 2 high resistive layer was introduced into Sb 2 Se 3 solar cells. Due to the introduction of SnO 2 , overall performance, especially J sc , was improved and champion device was achieved with efficiency of 4.77%. Image 1 • Sb 2 Se 3 solar cells were deposited by pulsed laser deposition for the first time. • PLD-Sb 2 Se 3 thin film has a bandgap of 1.21 eV and grain size is 200–250 nm. • PLD-Sb 2 Se 3 with thickness of 400 nm is more suitable for solar cells. • The introduction of SnO 2 improves device performance, especially J sc. [ABSTRACT FROM AUTHOR]

To address the growing and urgent need for quick and accurate food spoilage detection systems as well as to reduce food resource wastage, recent research has focused on intelligent bio-labels using pH indicators. Accordingly, we developed a dual-channel intelligent label with colorimetric and fluorescent capabilities using black lycium anthocyanin (BLA) and 9,10-bis(2,2-dipyridylvinyl) anthracene (DSA4P) as colorimetric and fluorescent indicators within a composite film consisting of chitosan (Cs), whey protein (Wp), and sodium tripolyphosphate (STPP). The addition of STPP as a cross-linking agent significantly improved the hydrophobicity, mechanical properties, and thermal stability of the Cs/Wp composite films under low pH conditions. After the incorporation of BLA and DSA4P, the resulting dual-channel intelligent label (Cs/Wp/STPP/BLA/DSA4P) exhibited superior hydrophobicity, as indicated by a water contact angle of 78.03°. Additionally, it displayed enhanced mechanical properties, with a tensile strength (TS) of 3.04 MPa and an elongation at break (EAB) of 81.07 %, while maintaining a low transmittance of 28.48 % at 600 nm. After 25 days of burial in soil, the label was significantly degraded, which showcases its eco-friendly nature. Moreover, the label could visually detect color changes indicating volatile ammonia concentrations (25–25,000 ppm). The color of the label in daylight gradually shifted from brick-red to light-red, brownish-yellow, and finally light-green as the ammonia concentration increased. Correspondingly, its fluorescence transitioned from no fluorescence to green fluorescence with increasing ammonia concentration, gradually intensifying under 365-nm UV light. Furthermore, the label effectively monitored the freshness of shrimp stored at temperatures of 4 °C, 25 °C, and − 18 °C. Thus, the label developed in this study exhibits significant potential for enhancing food safety monitoring. [Display omitted] • A colorimetric and fluorescent dual-channel label was developed. • DSA4P is a new pH-sensitive fluorescent molecule for solid film systems. • Black lycium anthocyanins exhibit robust color responsiveness. • The label containing sodium tripolyphosphate had excellent mechanical properties. • The dual-channel intelligent label was exhibited high sensitivity to biogenic amine. [ABSTRACT FROM AUTHOR]

The effects of annealing ambient on the structural and transport properties of epitaxial La0.7 Ba0.3MnO3 films suffering large compressive strain on LaAlO3 substrates (LBMO/LAO) have been investigated. Independent of oxygen or argon ambient, a high temperature (900 °C) post-annealing process leads to a c-axis contraction, which can be attributed to the oxygen transfer from the in-plane to the out-of-plane direction. Meanwhile, the transport properties are similar with each other for both the Ar-annealed and O2-annealed films. The comparison of the ambient annealing effects between the highly strained LBMO/LAO films and negligibly strained LBMO films on SrTiO3 substrates indicates that a large in-plane compressive strain favors decreasing oxygen deficiency in the films, especially in the ab-plane. [ABSTRACT FROM AUTHOR]

In this paper we report the epitaxial CaSnO 3 (CSO) thin films grown on LaAlO 3 (001) single crystal substrates with thickness ranged from 34 nm to 268 nm by pulsed laser deposition. The microstructures of the films were investigated by high-resolution X-ray diffraction, including conventional θ-2θ linear scans and reciprocal space mappings (RSMs). The thickness dependent strain states and lattice distortion of CSO films were characterized by the in-plane and out-of-plane lattice parameters that were extracted from the symmetry and asymmetry RSMs. The optical properties of CSO films were investigated by measuring the optical transmittances. The band gaps increase gradually from 4.95 eV to 5.38 eV with the film thickness decreasing, which was attributed mainly to the quantum-size effect. The band structure was also investigated theoretically using density-functional theory. The results show that CSO is an indirect band gap semiconductor with the band gap of 3.0 eV. Such a transparent wide band gap semiconductor should be of high interest in epitaxial heterojunction and optical device application. [ABSTRACT FROM AUTHOR]

The traditional sol-gel process usually takes a long time to form a stable Cu 2 ZnSnS 4 (CZTS) sol-gel solution, which increases the whole process time. In this paper, an electrodeposition assisted sol-gel process was employed to reduce the solution preparation time. Cu was electrodeposited on Mo surface and ZnSnS sol-gel was rotated on Cu surface to prepare CZTS films. The solution preparation time was reduced from 12h to 30min. The mechanism of CZTS phase formation with sol-gel method assisted by electrodeposition was studied. Cu 3 SnS 4 phase was formed during the electrodeposition assisted sol-gel process, while Cu 2 SnS 3 phase was formed when the CZTS precursor during sol-gel process. Cu content was rich at the beginning of the reaction to form Cu 3 SnS 4 during the electrodeposited assisted sol-gel process. CZTS films with Cu/(Zn + Sn) of 0.84 and Zn/Sn of 1.03 were prepared by sol-gel method assisted by electrodeposition. Compared with CZTS films prepared by sol-gel method, CZTS films prepared by this method have larger and more uniform grains. It is also found that the thickness of MoS 2 layer was thinner than the one prepared by sol-gel method. • An electrodeposition assisted sol-gel method was employed to prepare CZTS films. • The solution preparation time was reduced from overnight to 30min. • The grains of CZTS films prepared by this method were larger and more uniform than the one prepared by sol-gel method. • Electrodeposited Cu helped to suppress the formation of MoS 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • CH 3 NH 3 Pb(I 1-x Br x) 3 perovskite thin films are successfully applied as copper-free back contact layers for CdTe solar cells. • The facile deposition process of back contact layers. • The uniformity of CdTe solar cell is improved after applying CH 3 NH 3 Pb(I 1-x Br x) 3 back contact layers. • CdTe solar cell with a CH 3 NH 3 Pb(I 1-x Br x) 3 back contact layer exhibits good stability. In this study, bromide-iodide lead perovskite (CH 3 NH 3 Pb(I 1−x Br x) 3) thin films were fabricated and applied as copper-free back contact layers for CdTe solar cells. The results reveal that the open-circuit voltage (V oc) and fill factor (FF) of the CdTe solar cells are greatly enhanced by the utilization of perovskite back contact layers. This is mainly due to the evidently reduced charge transportation barrier at the back contact, which is verified by temperature-dependent current–voltage (J-V-T) and apparent quantum efficiency (AQE) measurements. Specifically, after the application of perovskite back contact layer, the best-performing device shows 15.80% improvement in efficiency (from 10.82 to 12.53%), with V oc and FF increasing by 3.94% and 6.91%, respectively. Besides, the overall uniformity of the solar cells is also improved by the perovskite back contact, suggested by laser beam induced current (LBIC) results. Further simulation results confirm the experimental results and clarify the optimized cell performance by perovskite back contact layer in terms of both energy band alignment and charge carriers' recombination. In addition, in the simulation section, we have also investigated the effect of the bandgap, thickness and doping level of perovskite and the doping level of CdTe on the cell performances. The experiments and the numerical simulation reported in this work suggest perovskite a potential copper-free back contact layer for the fabrication of efficient CdTe solar cells. [ABSTRACT FROM AUTHOR]

Highlights: [•] CdTe films were deposited by PLD at high substrate temperatures (400°C, 550°C). [•] CdTe films were achieved under the atmosphere (1.2Torr) of Ar mixed with O2. [•] Deposited CdTe films were cubic phase and had strong (100) preferred orientation. [•] Scanning electron microscope (SEM) showed an average grain size of 0.3–0.6μm. [•] The ultra-thin film (CdS/PLD-CdTe) solar cell with efficiency of 6.68% was made. [ABSTRACT FROM AUTHOR]

Abstract: In order to further decrease the fabrication cost, a technology of close-spaced sublimation under Ar–O2 mixture atmosphere has been studied. A deposition method of CdTe thin films on smooth glass substrates has been developed. The structural characteristics of CdTe films, which are deposited on glass substrate and CdS/SnO2:F/glass substrate, have been compared. The effects of oxygen partial pressure on the structure and characteristics have been investigated and the preferred orientation was quantificationally studied, which shows that there are the same structures of CdTe thin films on both kinds of substrates, if these films are deposited in an appropriate close-spaced sublimation process. Then the optical and electrical properties of CdTe films on glass substrates are studied, and the effects of post-treatment on the properties are observed. These results have been used to prepare CdS/CdTe/ZnTe:Cu solar cells. [Copyright &y& Elsevier]

• Window layer CdS was prepared by pulsed laser deposition. • As the pulse bias voltage increases from 0 V to 1000 V, the band gap of CdTe film decreases from 1.516 eV to 1.485 eV. • Pulse bias effectively improves the roll-over phenomenon of CdTe solar cells. • The efficiencies of CdTe solar cells prepared with or without pulse bias are 6.07% and 2.29%, respectively. A new method of efficiency of CdTe thin film solar cells has been proposed. In view of the characteristics of pulsed laser deposition (PLD) and combined with high power pulse bias power supply, CdTe thin films under 0, 500, 750, and 1000 V pulse bias were prepared on FTO substrates, and solar cells with FTO/CdS/CdTe/Au structure were formed. The crystal structure, vibration mode, morphology, and optical properties of the CdTe thin films deposited at different pulse bias were studied by XRD, Raman, SEM, UV–Vis spectrophotometer measurement. X-ray diffraction analysis indicated the prepared CdTe thin films had a strong (1 1 1) preferentially oriented cubic sphalerite structure. The transmission spectrum showed that with the increase of pulse bias, the absorption of CdTe films gradually moved towards the long-wave direction, and the optical bandgap decreased from 1.516 to 1.485 eV. We further fabricated FTO/CdS /CdTe/Au solar cells, with improved efficiency from 2.29% to 6.07% and excellent response performance over a long-wavelength range of over 900 nm, and the pulse bias voltage effect was significant. [ABSTRACT FROM AUTHOR]

The magnetocrystalline anisotropy of La0.67Ba0.33MnO3 (LBMO) epitaxial films suffering large compressive strain on LaAlO3 (LAO) substrates (LBMO/LAO) was investigated by ferromagnetic resonance (FMR) in the temperature range between 2 and 320 K. By mapping out the dependence of the FMR position on the angle between the applied magnetic field and crystallographic axes of the films, a large easy-plane anisotropy has been found in such compressive strained LBMO films, which is in contrast to the general tendency presented in strained manganite films. Furthermore, the excellent epitaxial crystallographic orientation due to the LAO substrates gives rise to an appreciable fourfold symmetry of the in-plane anisotropy with easy-axis along the [110] direction. The results are discussed by taking tolerance factor and giant magnetostriction of Ba-doped manganites into account. [ABSTRACT FROM AUTHOR]

Epitaxial growth of CoSi[sub 2] by solid state reaction of Co/a-Si/Ti/Si(100) is investigated. A Ti/a-Si composite interlayer is used to modify the diffusion barrier and influence the epitaxial growth process. The epitaxial quality of the CoSi[sub 2] is improved compared to the film grown by Co/Ti/Si reaction. A multielement amorphous layer is formed by a solid-state amorphization reaction at the initial stage of the multilayer reaction. This layer acts as a diffusion barrier, which controls the atomic interdiffusion of Co and Si while limiting the supply of Co atoms. CoSi[sub 2] grows as the first phase and the growth interface of the epitaxial CoSi[sub 2] is at both the CoSi[sub 2]/Si and CoSi[sub 2]/CoSi interfaces. Investigation of the growth kinetics shows that the activation energy of CoSi[sub 2] formation is larger than that without an amorphous Si layer. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A low electric resistive and stable ohmic back contact are crucial to the commercial application of CdTe solar cells. In this study the Sb 2 Te 3 thin film is employed as a buffer layer in the back contact of CdTe solar cells. The Sb 2 Te 3 thin films are deposited at different substrate temperature by pulsed laser deposition and then characterized to investigate the thin film properties, firstly. Hall measurements shows the Sb 2 Te 3 thin film presents strong p-type semiconductor features with high Hall mobility and carrier concentration. CdTe solar cells with Sb 2 Te 3 buffer layer in different layer thickness and deposition temperature are fabricated to obtain the optimal experiment conditions for device performance. The dark J-V curve of CdTe solar cell with Sb 2 Te 3 buffer layer exhibits a typical diode curve without roll-over phenomenon. An insertion of Sb 2 Te 3 buffer layer eliminates the Schottky barrier resulting in remarkable enhancement of open circuit voltage, short-circuit current and fill factor. Besides, the external quantum efficiency gets improvement in almost all of the absorber wavelength compared to the cells with Au-only contact. [ABSTRACT FROM AUTHOR]

Focuses on visible electroluminescence from semitransparent gold film/extra thin silicon-rich silicon oxide (SiO) film/p-Si diodes at room temperature. Use of the magnetron sputtering technique; Types of luminescence centers in the SiO films; Visible light emitted by electron-hole pairs.

Sb 2 S 3 has a unique one-dimensional structure-composed (Sb 4 S 6) n ribbons leads to strong anisotropic carrier transport characteristic: carrier transport along the (Sb 4 S 6) n ribbon is more efficient than other ribbons. Therefore, it's crucial to control the direction of grain growth along the (hk1) orientation. In this work, the close space sublimation method was utilized to fabricate Sb 2 S 3 thin films with a systematic al regulation of substrate temperature. The results demonstrate that optimized Sb 2 S 3 thin film presented preferred orientation at the direction of (hk1). The champion device based on Au and Ni electrodes achieved a power conversion efficiency (PCE) of 3.06% and 1.69%, respectively. Schematic diagram of the close space sublimation system. [Display omitted] • The (hk1)-oriented Sb 2 S 3 thin films were prepared by close space sublimation method. • Study of the effect of different substrate temperatures on the structure and morphology of Sb 2 S 3 thin films. • Solar cells with structure of FTO/TiO 2 /CdS/Sb 2 S 3 /Ni were fabricated. • Ni was firstly used as the electrode for Sb 2 S 3 solar cells. [ABSTRACT FROM AUTHOR]

AlSb is a new type of optoelectronic material with wide potential application prospects, but the applications of AlSb thin films for solar cells were few reported before, owing to the intrinsic drawbacks of deliquescence for AlSb. In this work, four types of AlSb/Sb stacks were fabricated by using pulsed laser deposition: (1) AlSb/Sb (5 nm), (2) AlSb/Sb (10 nm), (3) AlSb/Sb (15 nm) and (4) the in situ annealed AlSb film covered with Sb film which thickness is 15 nm. The experimental results indicate that the thicker the Sb layer deposited on the surface of the AlSb film is, the lower the degree of deliquescence will be. XRD measurements showed that the AlSb/Sb stacks were not deliquesced completely after exposed to air for 48 h. The EDS spectrum suggested that the percentage of oxygen atoms in the annealed AlSb film covered with Sb (15 nm) was smaller than the unannealed. The SEM morphology analysis revealed the deliquescence of AlSb film: the local film deliquesced to form sand inclusions first, after then the gradual increased of the sand inclusions lead to all deliquescence of the crystalline AlSb. [ABSTRACT FROM AUTHOR]

From the view of multi-scale structures of hydroxypropyl starch (HPS)/carbon nanotube (CNT) nanocomposite films, the film physicochemical properties were affected by comprehensive factors including molecular interaction, short range molecular conformation, crystalline structure and aggregated structure. The less original HPS hydrogen bonding that was broken, less decreased order of HPS short range molecular conformation, lower film crystallinity and larger size of micro-ordered regions contributed to higher tensile strength and Young’s modulus of the film with CNT content of 0.5% (g/g, CNT in HPS). The higher film overall crystallinity and larger size of micro-ordered regions of the film with CNT content of 0.05%–0.3% compared with those of control contributed to better film barrier property. The addition of CNT with the content of 0.05%–0.5% broke the original HPS hydrogen bonding and decreased the order of starch short range molecular conformation, which counteracted the positive effect of CNT on the thermal stability of the material, thus thermal degradation temperature of these nanocomposite films did not increase. But the sharp increase of film crystallinity increased film thermal degradation temperature. This study provided a better understanding of film physicochemical properties changes which guides to rational design of starch-based nanocomposite films for packaging and coating application. [ABSTRACT FROM AUTHOR]

Oxygen incorporation into ZnSe thin films in Ar/O 2 or O 2 ambient during radio-frequency sputtering was studied in this paper. With the increase of oxygen partial pressure ratio, the poor crystalline quality occurred in the films accompanying with a SeO 2 secondary phase. The values of optical band gap for the films increased after light oxygen doping, ranging from 2.65 to 2.88 eV, which indicates the formation of ZnSeO ternary compounds. The near-band edge emission was observed in all samples, i.e., electronic transitions from the valence band to the conduction band. Nevertheless, heavy incorporation of O in ZnSe thin films led to the formation of the thin films with wide energy band gap (∼5.61 eV) and high optical transmittance (∼90%). X-ray photoelectron spectroscopy spectra indicate that oxygen atoms ionized by plasma enhanced the formation of SeO 2 bonds with Se of ZnSe under the non-equilibrium conditions and many oxygen ions incorporated in the random sites, resulting in the formation of amorphous states. [ABSTRACT FROM AUTHOR]

The band gap of CdS (E g = 2.4 eV) was narrow, which made it unable to transmit short-wave sunlight through the CIGS absorber layer. Zn(O,S) thin film, prepared by doping O into ZnS, had a wider band gap, and the raw material was green and non-toxic, making it suitable as a buffer layer for solar cells. However, CBD-Zn(O,S) usually takes longer than CdS deposition. In this work, By shortening the deposition time through the fast hydrolysis of TAA. Na 3 NTA was added in the solutions to improve the quality of Zn(O,S) thin films. The effect of Na 3 NTA concentration on the complex ion contents was investigated. When Na 3 NTA was added at a concentration of 0.04 M along with TAA (0.04 M), the film had a high T% of 88.6%, E g of 3.76 eV, and a dense grain distribution. ZnS and ZnO grew at (111) and (100) crystals, respectively. Raman and XPS analyses showed the existence of Zn–S and Zn–O bonds, indicating the high crystalline quality of the Zn(O,S) thin films prepared with CBD. Finally, when the optimal concentrations of ZnSO 4 , NH 4 OH, Na 3 NTA, and TAA were 0.04 M, 0.48 M, 0.04 M, and 0.04 M, respectively, the prepared Zn(O,S) thin films could be used as a cadmium-free buffer layer for solar cells. • NH 4 OH and Na 3 NTA were mixed to improve the quality of grain growth of Zn(O,S). and optimized. • The microscopic morphology and the optical properties of Zn(O,S) were optimized. • The effect of pH on complex ion generation during complexation was simulated by Medusa software. • The concentrations of Na 3 NTA, and TAA were optimized, Zn(O, S) thin films, used as cadmium-free buffer layer for solar cells, were prepared. [ABSTRACT FROM AUTHOR]

Transparent and conductive Ta doped BaSnO 3 (BaSn 1−x Ta x O 3 , BSTO) films with x = 0–0.15 were epitaxially grown on MgO single crystalline substrates by a pulsed laser deposition method. The effects of Ta ions incorporation on the microstructure, electrical and optical properties of BSTO films were investigated. X-ray diffraction measurements indicate that the out-of-plane lattice parameters increase gradually with Ta concentration increasing, and the films are relaxed due to the large lattice mismatch between the films and substrate. Atomic force microscopy images reveal that all the films have smooth surface and low roughness. X-ray photoelectron spectra of BSTO films confirm that the Ta ions are presented in the +5 state. The lowest room-temperature resistivity and the highest carrier concentration and Hall mobility were observed in BSTO film at x = 0.07, with the values of 2.525 mΩcm, 5.024 × 10 20 cm −3 , and 4.921 cm 2 /Vs, respectively. Temperature dependent resistivity behavior shows that the BSTO films with low doping content exhibit metal-semiconductor transition at low temperature. The optical transmittances of all BSTO films are more than 80% in the visible region. The optical band gaps were found to increase from 3.52 to 4.23 eV with the increase of Ta doping content and can be attributed to the Burstein-Moss effect. Thus, the superior electrical and optical properties of Ta doped BaSnO 3 films are comparable to that of La and Sb doped BaSnO 3 films, and have potential applications in the optoelectronic devices. [ABSTRACT FROM AUTHOR]

Transparent conductive oxide (La 0.07 Ba 0.93 )SnO 3 (LBSO) thin films with thickness ranged from 220 nm to 11 nm were epitaxially grown on MgO substrate by pulsed laser deposition. The effect of thickness on the structural, transport, and optical properties of LBSO thin films was investigated in detail. With the film thickness decreasing, x-ray diffraction characterizations show that the LBSO (002) diffraction peak has no obvious shift, but the values of the full width at half maximum increase gradually from 0.608° to 1.136° due to the deterioration of crystalline quality of LBSO films. Atomic force microcopy reveals that the root-mean-square surface roughness of LBSO films decreases from 3.93 to 0.268 nm with film thickness decreasing. The lowest resistivity value of 1.181 × 10 −4 Ωcm at room temperature was observed in 220 nm thick films, with the highest carrier mobility of 41.06 cm 2 V −1 s −1 and carrier concentration of 8.377 × 10 20 cm −3 . Furthermore, the resistivity increases gradually with the decrease of LBSO film thickness. Temperature dependent resistivity measurements indicate that the metal-semiconductor transition temperature of LBSO thin film changes regularly with the film thickness. The optical band gap of LBSO thin film decreases from 4.58 to 3.55 eV with decreasing the thickness, which was explained by the Burstein-Moss effect. [ABSTRACT FROM AUTHOR]

BaSnO 3 (BSO) films were grown epitaxially on MgO substrate under a wide range of pressures (from 20 to 0.03 Pa) by pulsed laser deposition. The structural, electrical, and optical properties of films were investigated. X-ray diffraction characterization reveals that the film unit cell volume increases gradually with decreasing the growth oxygen pressure while preserving the perovskite structure. The transport property measurement suggests that the film resistivity was tuned with variation from nearly insulator to metallic conductor by controlling the grown oxygen pressure, which was attributed to the presence of more oxygen vacancies in films during deposition. Remarkably, the lowest room-temperature resistivity of 8.07 × 10 −4 Ω cm was obtained in film grown in 0.3 Pa without any dopant, with the carrier concentration and mobility of 7.60 × 10 20 cm −3 and 10.81 cm 2 /V respectively. All the BSO films have high transmittance of more than 80% in the visible range regardless of the oxygen pressure, whereas the optical band gaps increase from 3.49 to 3.70 eV, which was explained by the Burstein-Moss effect. [ABSTRACT FROM AUTHOR]

The Cadmium telluride (CdTe) thin film has been prepared by physical vapor deposition (PVD), the Ar + O 2 pressure is about 0.9 kPa. This method is a newer technique to deposit CdTe thin film in large area, and the size of the film is 30 × 40 cm 2 . This method is much different from the close-spaced sublimation (CSS), as the relevance between the source temperature and the substrate temperature is weak, and the gas phase of CdTe is transferred to the substrate by Ar + O 2 flow. Through this method, the compact and uniform CdTe film (30 × 40 cm 2 ) has been achieved, and the performances of the CdTe thin film have been determined by transmission spectrum, SEM and XRD. The film is observed to be compact with a good crystallinity, the CdTe is polycrystalline with a cubic structure and a strongly preferred (1 1 1) orientation. Using the CdTe thin film (3 × 5 cm 2 ) which is taken from the deposited large-area film, the 14.6% efficiency CdS/CdTe thin film solar cell has been prepared successfully. The structure of the cell is glass/FTO/CdS/CdTe/graphite slurry/Au, short circuit current density ( J sc ) of the cell is 26.9 mA/cm 2 , open circuit voltage ( V oc ) is 823 mV, and filling factor (FF) is 66.05%. This technique can be a quite promising method to apply in the industrial production, as it has great prospects in the fabricating of large-area CdTe film. [ABSTRACT FROM AUTHOR]

(Ba 1-x Gd x )SnO 3 (BGSO) (x = 0–0.15) films were epitaxially grown on MgO substrates by pulsed laser deposition. Structure analysis was performed using X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy. Transport properties were investigated by Hall effect and temperature dependent resistivity measurement. Results show that the film resistivity decreases systematically with increasing Gd doping concentration. The lowest room-temperature resistivity of 6.18 mΩcm was observed in film at x = 0.07, with the metal-insulator transition at 30 K, which was attributed to the formation of a degenerate band in films. Optical transmission spectra measurement shows that all the BGSO films have high transmittance of more than 80% in the visible range. The band gap variation with the Gd doping concentration was interpreted by the Burstein-Moss effect. Excellent optical and electrical properties suggest that BGSO films have potential applications in the optoelectronic devices as transparent and conducting oxide material. [ABSTRACT FROM AUTHOR]

As a new-type absorber material, antimony sulfide (Sb 2 S 3) possesses the advantages of earth-abundant elemental contents, low-toxic constituents, appropriate photoelectric properties, and unique one-dimensional crystal structure. We utilized the close space sublimation technique to deposit high-quality Sb 2 S 3 thin-film with (hk 1)-preferred orientation by controlling source temperature. Then, Sb 2 S 3 thin film solar cells with the superstrate structure of FTO/CdS/Sb 2 S 3 /Au were fabricated, achieving a conversion efficiency of 2.86%. To further enhance efficiency, co-selenization process was employed in the Sb 2 S 3 thin films by co-sublimation, which improve the crystallinity of films, increase grain size and form stronger (hk 1)-preferred orientation. In addition, co-selenization process can adjust band gap value and enhance junction quality. By these approaches, we enhanced the short circuit current density (Jsc) of Sb 2 S 3 solar cell efficiently. The Sb 2 S 3 solar cell fabricated by CSS achieved an efficiency of 4.45% using co-selenization process. These methods can be applied to other chalcogenides thin-film solar cells, providing a practical way for the device performance improvement. • Close space sublimation was employed to prepar Sb 2 S 3 thin film. • Sb 2 S 3 underwent the co-selenization process was synthesized by co-sublimation for the first time. • Sb 2 S 3 thin film solar cell obtained the efficiency of 2.86% by controlling the source temperature. • Se–Sb 2 S 3 soar cell fabricated by CSS achieved the efficiency of 4.45%, obtained an enhancement of 55.6%. [ABSTRACT FROM AUTHOR]

Abstract: Vanadium diselenide thin films were prepared by electron beam evaporation. The properties of vanadium diselenide thin films were investigated using X-ray diffraction, scanning electron microscope, transmission spectra, electrical and Hall measurements. To further investigate the application of vanadium diselenide thin films, device performance in CdTe solar cells with a vanadium diselenide layer was also studied. The results indicate that vanadium diselenide thin films had a stable hexagonal structure after annealing. The thin films were p-type semiconductor materials with the high work function and high carrier concentration. Vanadium diselenide thin films could form a good ohmic contact to CdTe solar cells. Thus, cell performance was greatly improved when introduced a vanadium diselenide buffer layer. [Copyright &y& Elsevier]

In this work, the CZTS absorbers were prepared by sol-gel method and the combination of electrodeposition and sol-gel method. The influence of Na and/or K incorporation on the thickness of MoS 2 during sulfurization process was investigated. XRD, Raman, and SEM characterizes presented that K incorporation could help to suppress the formation of MoS 2 , which induced to reduce the thickness of MoS 2. Additionally, Na and/or K doping could eliminate the existence of the voids and improve the quality of CZTS thin film. Besides, the CZTS absorbers fabricated by the combination process of electrodeposition and sol-gel shown a better adhesion than that fabricated by sol-gel method. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of MgTiO3 high-k dielectric have been prepared by RF magnetron sputtering deposition at various substrate temperatures. X-ray diffraction, atomic force microscopy were used to characterize the deposited films. Experimental results show that substrate temperature has little effect on the stoichinometry. The electrical properties of MgTiO3 metal–insulator–metal (MIM) capacitors were investigated at various deposition temperatures, Pt/MgTiO3/Pt/SiO2/n-Si, were studied. It is shown that the MgTiO3 (210 nm) MIM capacitor fabricated at 200 °C shows an overall high performance, such as a high capacitance density of ∼1.2 nF/um2, a low leakage current of 1.51 × 10−9 A/cm2 at 5 V, low-voltage coefficients of capacitance, and good frequency dispersion properties. All of these indicate that the MgTiO3 MIM capacitors are very suitable for use in Si analog circuit application or dynamic random access memory (DRAM) cell. [Copyright &y& Elsevier]

Abstract: The influence of boron (B)/arsenic (As) on X-ray photoelectron spectroscopy (XPS) study of NiSi formation on shallow junctions is investigated in this paper. The Ni-silicide film was formed after 30s soak anneal at 450°C on ultra shallow p+/n or n+/p junctions. The atomic ratio of Ni/Si profile in depth was probed by XPS and the results show that a uniform NiSi layer forms on B-doped p+/n junction while a non-uniform, Ni-rich silicide layer forms on As-doped n+/p junction. It does not agree with the results of other independent phase identification methods such as X-ray diffraction, Rutherford backscattering spectroscopy, and Raman scattering spectroscopy, which all demonstrate the formation of NiSi on both n+/p and p+/n junctions. Comparing the raw binding energy spectra of Ni and Si for each silicide film, the similar spectra for Ni signals are revealed. But the Si signals with an obviously smaller intensity is found to be responsible for the apparent Ni rich silicide formation on As-doped n+/p junction. It indicates that As atoms in the silicide film can affect the sputtering yield of Ni and Si, while no noticeable effect is observed for B atoms. More As atoms than B atoms segregation into the silicide layer is indeed verified by secondary ion mass spectroscopy. And micro-Raman scattering spectroscopy further confirms that the degree of crystallinity for NiSi on n+/p junction is inferior to that on p+/n junction. [Copyright &y& Elsevier]

Abstract: Ni and Ni(Pt) germanosilicide formation and their contact properties on n-type epitaxial Si0.84Ge0.16 have been studied in this work. It is revealed that compared to NiSi, NiSiGe has enhanced phase stability but worse morphology stability. It is also found that Pt incorporation in germanosilicidation improves the morphology of the germanosilicide film. The Schottky contact characteristics of NiSiGe and Ni(Pt)SiGe on n-SiGe were evaluated by current–voltage (I–V) technique at room temperature. NiSiGe/n-SiGe contact shows a Schottky barrier height (SBH) of 0.65eV with little difference from that of NiSi/n-Si contact. However, the contact shows a reduced SBH with a markedly increased ideality factor and leakage current when annealing temperature increases to 650°C, indicating thermal degradation of the contact quality. Pt incorporation increases the SBH to 0.73eV. In addition, its diode parameters such as SBH, ideality factor, and reverse leakage show better conformity during the whole annealing temperature range (from 450 to 650°C). Therefore, it is concluded that Pt interlayer between Ni and SiGe can modulate the barrier height of Ni germanosilicide and improve its contact properties. [Copyright &y& Elsevier]

Correction to: Applied Physics A (2021) 127:560 https://doi.org/10.1007/s00339-021-04704-5 In this article, the following affiliation for Dr. Mohsen Ghali was missing: Physics Department, Faculty of Science, Kafrelsheikh University, 33516 Kafrelsheikh, Egypt. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. [Extracted from the article]

Abstract: The structure and main manufacturing technologies of CdTe film solar cells of large area are reviewed. Among the technologies, some have been developed for application in a pilot manufacturing line. The high resistant SnO2 (HRT) thin films have been fabricated by PECVD. The effects of annealing on the structure and properties have been studied. A surface etching process of CdTe in low temperature and lower concentration of nitric acid has been developed. The Cd1− x Zn x Te ternary compound films have been studied. In order to improve the back contact layer, Cd0.4Zn0.6Te layer with 1.8 eV band gap as a substitute for ZnTe layer is introduced in CdTe cells. The effects of the technologies on performance of CdTe cells and feasibility of application in the modules are discussed. [Copyright &y& Elsevier]

Abstract: Ultrathin Vanadium nitride (VN) thin film with thickness around 10nm was studied as diffusion barrier between copper and SiO2 or Si substrate. The VN film was prepared by reactive ion beam sputtering. X-ray diffraction, Auger electron spectroscopy, scanning electron microscopy and current–voltage (I–V) technique were applied to characterize the diffusion barrier properties for VN in Cu/VN/Si and Cu/VN/SiO2 structures. The as-deposited VN film was amorphous and could be thermal stable up to 800°C annealing. Multiple results show that the ultrathin VN film has good diffusion barrier properties for copper. [Copyright &y& Elsevier]