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• An improved fitting method was developed to accurately measure ultrathin sample. • Accurately measured SAM have a mean thickness of 0.89 nm and a RI of 1.387. • Fabrication of ultra-thin SAM films using semiconductor fabrication techniques. • Non-contact characterization of thickness and optical property of ultrathin sample. A differential interference contrast (DIC) system was introduced to guide non-destructive ellipsometer metrology for characterizing ultrathin-film. Patterned self-assembled monolayer was fabricated as ultrathin-film samples. Furthermore, an improved fitting method was developed to describe the samples. The ellipsometer analysis revealed a mean thickness of 0.89 nm and a refractive index of 1.387 for the samples, consistent with Atomic Force Microscopy results and previous reports. These results validate well performance ellipsometers combination with DIC systems as preferred non-destructive characterization tools for determining the ultrathin film. Moreover, the potential capability of the DIC-guided ellipsometry technique was verified in the field of patterned ultrathin film measurements. [ABSTRACT FROM AUTHOR]

A newly oxospiro[indoline-3,4′-pyran]-5′-carbonitrile derivative has been synthesized and characterized by FT-IR, NMR spectroscopies, and elemental analysis. The compound thin film form has been prepared by spin coating technique. The optical absorbance, transmittance, and reflectance measurements were carried out in the wavelength (300–2500 nm) range. The absorption and dielectric parameters were determined and discussed. The electronic transition energies (2.56, 3.45& 3.97 eV) were deduced and correlated to the onset, optical, and transport gaps, respectively. The electrical resistance and Seebeck coefficient measurements revealed the n-type semiconducting behavior of the films. The detected rapid reversibility of the O 2 - chemisorption process on the surface of the present films at room temperature was exploited for the NH 3 gas sensing application. The revealed fast reversibility, low response (180/224 s) and recovery (3 s) times, good selectivity, as well as the long-term stability of the present films, prove their promises for RT-NH 3 gas sensing applications. [Display omitted] • Optical and electrical characterization of newly synthesized organic compounds. • Discussion of the electronic transition energies through HOMO-LUMO orbitals. • n-type conduction behavior revealing by the present film. • Proof of the film ability for RT-NH3 gas sensing. [ABSTRACT FROM AUTHOR]

• Relaxor ferroelectric PMN-PT films were epitaxially grown on SrTiO 3 buffered GaAs substrates. • XRD patterns confirm that the PMN-PT films are epitaxial grown on GaAs substrates. • Ferroelectric hysteresis loops were observed in PMN-PT films on GaAs. Relaxor ferroelectric Pb(Mg 1/3 Nb 2/3)O 3 -PbTiO 3 (PMN-PT) thin films were epitaxially grown on (001)-oriented SrTiO 3 buffered III-V semiconductor GaAs substrates by pulsed laser deposition. Detailed microstructural investigations of the films were carried out using X-ray diffraction, atomic force microscopy and transmission electron microscopy. Local piezoresponse force microscopy hysteresis loops confirm the ferroelectric nature of the PMN-PT thin films on GaAs. The results have demonstrated the practicality of integrating epitaxial PMN-PT films on semiconductor GaAs, which may pave the way to develop III-V semiconductor based opto-mechanical devices. [ABSTRACT FROM AUTHOR]

Ion beam tailored carbon thin films, inspired by their outstanding multifunctional properties, are drawing strong interest in a variety of fields, including optical devices, photonics, magnetic devices, solar cells and hard coatings. The role of initial film surface, a deciding factor for its applicability in optoelectronic devices, is worth studying. In this regard, present work investigates the role of initial film surface in 30 keV argon ion irradiation induced tailoring of structural, morphological and optical characteristics of as-deposited and annealed carbon thin films. For this, carbon thin films have been successfully grown over Si(100) using the RF sputtering of a carbon target and are thermally annealed at 400 °C. These synthesized and annealed films are subjected to 30 keV argon ion irradiation at different fluences of 1 × 1016, 3 × 1016 and 5 × 1016 Ar + cm−2. The synthesized films were found to be amorphous (a-C) which phase transformed to graphite like carbon (GLC) after annealing by seen by Raman analysis. Depth profiling by Rutherford Backscattering Spectrometry (RBS) revealed that these a-C and GLC films are stoichiometric of carbon element only. Drastic decrease in carbon concentration from 90 to 61 at. % with ordering of sp2 sites for synthesized & sputtered films whereas disordering of sp2 sites with decrease in carbon concentration from 94 to 67 at. % has been seen for annealed & sputtered films. Initially rough film surfaces transformed into smooth surfaces with increase in argon ion fluence. Optical energy gap decreases while conductivity increases with increase in argon ion fluence. It has been demonstrated that 30 keV Ar+ sputtering resulted in optically and electrically conductive a-C and GLC films with smooth surfaces, making it a good candidate for opto-electronic applications. • Phase transformation to Graphite like carbon after annealing of as-deposited a-C films • Drastic decrease in C concentration from 90 to 61 at. % with ordering of sp2 sites for synthesized & sputtered films • Disordering of sp2 sites with decrease in C concentration from 94 to 67 at. % for annealed & sputtered films • All argon sputtered a-C films showed semiconductor behavior (decrease in optical energy gap & increase in conductivity) • Initial film surface plays crucial and deciding role in response to 30 keV Ar + sputtering • Annealed & sputtered films show more pronounced tailoring of optical and electrical characteristics [ABSTRACT FROM AUTHOR]

Propane dehydrogenation received more and more attention with the increase in propylene demand and the growing extraction of shale gas. However, traditional catalysts require feed dilution with hydrogen or inert gas, thereby lowering per-pass propylene productivity. We report here, a novel hybrid nanostructure catalyst (denoted as PtSn/@-ZrO 2 /SBA-15) for PDH with high initial propylene formation rate (15.15 mol·g Pt −1·h−1) under pure propane feed, excellent propylene selectivity (> 95 %), and especially good stability even if the propane conversion closed to thermodynamic limits. During the reaction process, the tin species were effectively stabilized. XPS, H 2 -TPR and a series of characterizations indicated that those superior activities and appreciable long-term stability are stemmed from synergistic catalysis and strong interface electronic effect between PtSn nanoparticles and non-crystal semiconductor film (monolayer-dispersed ZrO 2) in SBA-15. Our findings provide a new perspective on the preparation of redox catalysts. [Display omitted] • Developed a novel hybrid nanostructure catalyst PtSn/@-ZrO 2 /SBA-15. • Excellent catalytic performance in direct propane dehydrogenation over PtSn/@-ZrO 2 /SBA-15 catalyst. • Synergistic catalysis and strong interface electronic effect between PtSn nanoparticles and non-crystal semiconductor ZrO 2 film. [ABSTRACT FROM AUTHOR]

In this study, an in-depth electrochemical characterization of a precipitation hardened 17-4 stainless steel (SS17-4PH) was carried out in combined acidic, alkaline, and chloride environments. The characterizations were carried out through polarization-EIS analysis, Mott-Schottky analysis to characterize the semiconducting properties of the thin oxide films, and a post-mortem scanning electron microscopy (SEM-EDX) analysis to reveal the morphologies after anodic polarization. The electrochemical measurements revealed that the corrosion rate of SS17-4PH samples in acidic-chloride solutions is higher than the sample polarized in only NaCl or NaOH solution. From the Mott Schottky results, the straight lines with a positive slope obtained for the steel samples in different test media show that there is no change in the semi-conducting properties of the passive film. For samples polarized in acidic-chloride medium, the microstructural examination revealed the formation of a foot-like pit and zig-zag degradation structure. This was attributed to the presence of acid in the test media, and the deposition of corrosion products on the sample surface. [Display omitted] [ABSTRACT FROM AUTHOR]

A pulsed reactive magnetron sputtering system with a tungsten target and a gas mixture of argon and oxygen was investigated as a source for the deposition of semiconductor WO 3 thin films on soda lime glass substrates and on the glass with transparent conductive SnO 2 :F (FTO) electrode. The reactive sputtering process was performed in HiPIMS mode with low pulse repetition frequency f p ≈ 50–100 Hz and short pulse duration in HiPIMS discharge T on = 100 μs. The second mode investigated was the mid-frequency (MF) magnetron discharge with pulse frequency f p = 40 kHz and pulse length T on = 15 μs. The plasma parameters were investigated for both HiPIMS and MF modes using the planar RF probe operating at the frequency f probe = 350 kHz and the grid QCM with biased collector electrode. Ion density n i and tail electron temperature (T e) were determined in both pulsed reactive magnetron sputtering discharge modes with time resolution. The maximum value n i ≈ 5 · 1017 m−3 was found in the reactive HiPIMS mode, and the maximum value n i ≈ 7 · 1016 m−3 was found in the reactive MF (40 kHz) mode. The degree of ionization of sputtered particles in reactive HiPIMS was determined for different values of (Q O2) and was found to be in the range of r i ≈ 0.1–0.3. The deposition rate determined by QCM in reactive HiPIMS was practically independent on (Q O2), but in the case of reactive MF, the measured deposition rate decreased significantly with increasing (Q O2). The WO 3 films deposited in both modes have a predominantly monoclinic crystal structure. The light and dark conductivity and the light/dark conductivity ratio (L d) were measured under dark conditions and UV light illumination. At higher (Q O2), the maximum value of L d ≈ 300 was found for MF deposited WO 3 and the maximum value of L d ≈ 30 was found for HiPIMS deposited WO 3. The photoelectrochemical measurement of WO 3 deposited on FTO electrodes confirmed the n-type conductivity, and these films functioned as photoanodes in photoelectrochemical cells. MF deposited WO 3 films systematically exhibited slightly higher photocurrents than HiPIMS deposited WO 3. It was shown that these optimum photocurrents for HiPIMS and MF were found at Q O2 ≈ 80 sccm and could not be improved by further increasing of (Q O2). [Display omitted] • HIPIMS and MF reactive pulsed sputtering were used to deposit semiconductor crystalline WO 3 films with photoresponse. • Plasma parameters in HiPIMS and MF sputtering systems were determined by RF probe and g-QCM. • HiPIMS deposited WO 3 films have significantly larger crystallites than MF deposited WO 3 films. • MF deposited WO 3 films have higher photoresponse and lower dark conductivity than HiPIMS deposited WO 3. [ABSTRACT FROM AUTHOR]

• This work proposes a new method for growing epitaxial films on foreign substrates. • In particular, GaN epitaxial films on Si, SiC and sapphire substrates. • The proposed method makes it possible to obtain high-quality and flat epitaxial films, regardless of the material of the substrate or epitaxial film, regardless of the diameter of the substrate or the thickness of the epitaxial film, without any buffer layers, without carrying out any additional operations and costs. • A round bimetallic plate located under the substrate bends the substrate in the required direction to the desired value at the growth temperature, maintains the bend during growth, and gradually reduces the bend of the fabricated heterostructure during cooling, in proportion to the thermal contraction of the epitaxial film. • This will make it possible to obtain flat heterostructures with high-quality epitaxial film. In recent years, to mitigate the effects of climate change, countries' transition to the green economy has accelerated, and thereby, the demand of semiconductor industry for wide-gap semiconductors such as SiC and GaN has increased dramatically. These semiconductors are expensive. To reduce the price of the final product, industrial production of thin epitaxial films of sought-after semiconductors on accessible and cheap substrates, such as Si and sapphire, is being developed. When growing epitaxial films on foreign substrates, the resulting heterostructure bends, becomes concave or convex, due to a mismatch between the coefficients of thermal expansion (CTE) of the substrate and the epitaxial film. As a result, the quality of the epitaxial film deteriorates and further processing of the resulting heterostructures in production lines becomes difficult or even impossible. The essence of the proposed new method is that the epitaxial film is grown not on a flat, but on a pre-curved substrate with the expectation that after cooling the fabricated heterostructure to room temperature, the heterostructure will take a flat shape due to the difference in the CTE of the epitaxial film and the substrate. A round bimetallic plate, located under the substrate, bends the substrate in the required direction to the desired value at the growth temperature, and gradually reduces the bend of the fabricated heterostructure during cooling, in proportion to the thermal contraction of the epitaxial film. This allows obtaining qualitative and flat epitaxial films, regardless of the material of the substrate or epitaxial film and the diameter of the substrate or thickness of the epitaxial film, without any buffer layers or carrying out any additional operations and costs. [ABSTRACT FROM AUTHOR]

Crystal violet (CV) residues in Marine food have produced a severe health threat in human life. In this study, we proposed a semiconductor surface-enhanced Raman scattering (SERS) sensor of corrosion-resistant Polyaniline/Graphene oxide (PPy/GO) film by electrochemical growth method to detect CV residues in fresh fish tissue. A PPy/GO dispersion solution was one-step deposited on a stainless steel sheet surface by electrochemical polymerization process to form a PPy/GO composite film acting as a semiconductor SERS substrate. Since the substrate of PPy/GO film was mainly composed of GO sheet without other metals, it had a good corrosion resistance. The SERS enhancement factor and charge transfer intensity P CT of PPy/Go SERS substrate for CV molecules were up to 1.18 × 106 and 0.903, respectively. Furthermore, the limit of detection (LOD) of PPy/GO SERS substrate could reach 1.58 nM. In addition, SERS sensor of PPy/GO film could identify CV residues in fresh fish tissues, and its recovery rate was 91.8 %–107 %. This preparing method and detecting method we proposed PPy/GO SERS substrate provide a new pathway for detecting CV residues in Marine food. In this study, we proposed a semiconductor surface-enhanced Raman scattering (SERS) sensor of corrosion-resistant Polyaniline/Graphene oxide (PPy/GO) film by electrochemical growth method to detect CV residues in fresh fish tissue. [Display omitted] • The semiconductor SERS sensor on PPy/GO substrate was prepared by one-step synthesis method. • The Raman signal enhancement of this sensor mainly relies on charge transfer resonance. • This sensor was suitable for the Marine environment with high salt and high humidity. [ABSTRACT FROM AUTHOR]

We report the microstructure, optical and electrical properties of Al 1.5 Ga 0.5 O 3 thin films implanted by 180 keV Fe and Co ions. The X-ray diffraction pattern confirmed rhombohedral structure with R 3 ‾ c space group for pristine and Fe-implanted films. The Co-implanted films showed amorphous structure. SRIM simulations suggested oxygen vacancy in the films. The atomic force microscopy confirmed the formation of spherical-shaped particles (17–20 nm) in Co-implanted GaAlO_Si_550 films. The RMS roughness of the GaAlO_Si_550 films increased from 19 nm to 25 nm at higher Co-ion implantation fluences. X-ray photoelectron spectroscopy supported the formation of oxygen vacancy and non-stoichiometry at surface of the films. Electrical conductivity of the films enhanced up to 10−2- 10−3 S/m by metallic Fe- and Co ion implantation. Optical band gap was found at ∼3.85 eV for GaAlO_Al_550 and ∼4.04 eV for GaAlO_Si_550 pristine films. Optical band gap was stabilized in the range of 3.75–4.52 eV for Fe- and Co-implanted films, which can be useful for opto-electronic device applications in the UV and deep blue region. • Microstructure, optical and electrical properties of Fe and Co implanted Al 1.5 Ga 0.5 O 3 films. • SRIM simulations and XPS study for implantation-induced structural formation. • The electrical conductivity of the implanted films enhanced up to 10−2 S/m. • The optical band gap of the films was found in the range of 3.77–4.52 eV. • The films can be useful for a wide range of opto-electronic applications in UV to IR regime. [ABSTRACT FROM AUTHOR]

In this study, the effects of the CF 4 plasma treatment on the amorphous indium gallium zinc oxide (IGZO) material were explored. The electrical characteristics of the IGZO-based field-effect transistor (FET) were also thoroughly examined to analyze the influence of the plasma treatment. Excellent adhesion of the sol-gel-based IGZO semiconducting film was achieved owing to the strong dipole moment of the AlO x F y layer created by the surface treatment. In particular, X-ray photoelectron spectroscopy depth profiles and transmission electron microscopy electron energy loss spectroscopy analyses provided clear evidence that fluorine atoms diffused into the Al 2 O 3 surface via the CF 4 plasma treatment. The formation of an AlO x F y layer at the IGZO/Al 2 O 3 interface is expected to be advantageous for reducing the interface trap density, thereby enhancing the critical transistor parameters. Additionally, the plasma-treated IGZO transistor demonstrated strong electrical bias stability under continuous gate bias stress conditions. Therefore, surface modification via CF 4 plasma treatment is proposed to boost the stability and performance of the device, offering a straightforward approach for integrated thin-film transistor circuitry in advanced display applications. Herein, we explored the effects of CF 4 plasma treatment on the amorphous indium gallium zinc oxide transistor. Excellent adhesion of the sol-gel IGZO semiconducting film was attained with strong dipole moment of the AlO x F y layer formed by CF 4 plasma treatment. The formation of the AlO x F y layer at the IGZO/Al 2 O 3 interface contributes to reducing the interface trap density, thereby improving the critical transistor performance. Strong bias stability of the plasma-treated IGZO transistor is also achieved, potentially realizing durable electrical circuit. [Display omitted] • Strong dipole moment of CF 4 plasma-induced AlO x F y layer leading to excellent adhesion of the IGZO semiconducting film. • In-depth XPS depth profile and TEM-EELS analyses for validating the diffusion of the fluorine atoms diffused into the Al 2 O 3. • Low interface trap density enabled by the formation of an AlO x F y layer enhancing the critical transistor parameters. • Strong electrical bias stability in IGZO transistor with CF 4 plasma treated Al 2 O 3 dielectric. [ABSTRACT FROM AUTHOR]

Multimodal multiscale characterization provide opportunities to study organic semiconducting thin films with multiple length scales, across multiple platforms, to elucidate crystallization mechanisms of the various microstructures that impact functionality. With polarized scanning transmission X‐ray and 4D‐scanning transmission electron microscopy, hybrid crystalline structures in rubrene thin films in which large crystalline domains surround a common nucleus and transition to a spherulite morphology at larger radii is observed. These high‐resolution techniques reveal how azimuthal orientational discontinuities at smaller radii are erased as spherulite morphology takes hold. In situ crystallization in the films with optical microscopy is also captured, discovering the importance of considering the initial temperature increase of a film during thermal annealing over the crystallization timescale. This kinetic information of the radial crystallization rate and of corresponding film heating kinetics is used to estimate the temperature at which the larger crystalline regions transition into a spherulite. By combining the results obtained from the different characterization modes, it is learned that thermal conditions can sensitively affect the crystallization of rubrene and other organic thin films. The observations suggest opportunities for more complex temperature‐dependent processing to maximize hybrid structures' functionality in organic thin films and demonstrate that multimodal studies deepen the understanding of structure‐function dynamics. [ABSTRACT FROM AUTHOR]

In this paper, SnO2: rGO compound thin films were deposited on glass substrates by spray pyrolysis method. For the synthesis of SnO2: rGO thin films, different amounts of reduced graphene oxides (0, 25, 50, 75, 100, and 150 mg) were added to the solution. Then, the influence of reduced graphene oxide, and annealing by hydrazine as a reducing agent on the structural, electrical, and optical properties of these films were investigated. The results of XRD analysis in all the samples showed the SnO2 phase is formed and the intensity of peaks increases relatively after reducing with hydrazine and increasing the value of rGO. FE-SEM images of SnO2: rGO samples showed that grain size and porosity decreased after reduction with hydrazine. An enhancement of electrical properties was observed with the addition of reduced graphene oxide and annealing under hydrazine. The minimum sheet resistance equal to 0.42 kΩ/sq. for SnO2: rGO (50 mg) thin films was obtained. The Hall effect experiment also showed the n-type conductivity of all synthesized thin films, and the carrier concentration was calculated to be 1021 cm−3. In addition, the band gap values of the films in the range of 3.58–3.72 eV were obtained and this method is a successful technique for tuning of the band gap of SnO2 thin films. [ABSTRACT FROM AUTHOR]

Zinc sulfide (ZnS) thin films prepared using the chemical bath deposition (CBD) method have demonstrated great viability in various uses, encompassing photonics, field emission devices, field emitters, sensors, electroluminescence devices, optoelectronic devices, and are crucial as buffer layers of solar cells. These semiconducting thin films for industrial and research applications are popular among researchers. CBD appears attractive due to its simplicity, cost-effectiveness, low energy consumption, low-temperature compatibility, and superior uniformity for large-area deposition. However, numerous parameters influence the CBD mechanism and the quality of the thin films. This study offers a comprehensive review of the impact of various parameters that can affect different properties of ZnS films grown on CBD. This paper provides an extensive review of the film growth and structural and optical properties of ZnS thin films influenced by various parameters, which include complexing agents, the concentration ratio of the reactants, stirring speed, humidity, deposition temperature, deposition time, pH value, precursor types, and annealing temperature environments. Various studies screened the key influences on the CBD parameters concerning the quality of the resulting films. This work will motivate researchers to provide additional insight into the preparation of ZnS thin films using CBD to optimize this deposition method to its fullest potential. [ABSTRACT FROM AUTHOR]

Orientation control over micropatterned crystalline organic semiconductor film is crucial to achieve high device performance with small variation in organic electronics. Here, using Au patterned SiO2 substrates, a method is reported to realize high‐resolution patterning and orientation control of crystalline organic thin films simultaneously. The vacuum deposited N,N‐dioctyl‐3,4,9,10‐perylene tetracarboxylic diimide (PTCDI‐C8) molecules can selectively diffuse to and nucleate on prepatterned Au stripes, resulting in patterned crystalline films with a preferential orientation distribution. Scanning tunneling microscope and high‐resolution atomic force microscope images reveal that the PTCDI‐C8 molecules first assemble on Au with perylene diimide cores in a laying down configuration, providing nucleation sites at the step edges for directional growth along the a‐axis of the molecule crystal. Subsequent deposition of molecules leads to orientated crystalline films growth due to the π packing of the perylene diimide cores, resulting in orientation control on micropatterned crystalline films. The finding provides a new strategy to grow oriented crystalline films for high device performance uniformity. [ABSTRACT FROM AUTHOR]

As a promising third-generation semiconductor, gallium oxide (Ga2O3) is currently facing bottleneck for its p-type doping. The doping process of conventional semiconductors usually introduces trace impurities, which is a major technical problem in the electronics industry. In this article, we conceived that the process complexity could be significantly alleviated, and a high degree of control over the results could be attained using the selective enrichment of liquid metal interfaces and harvesting the doped metal oxide semiconductor layers. An appropriate mechanism is thus proposed to prepare the doped semiconducting based on multicomponent liquid metal alloys. Liquid metal alloys with the certain Cu weight ratios in bulk are utilized to harvest Cu-doped Ga2O3 films, which result in p-type conductivity. Then, field-effect transistors were integrated using the printed p and n-type Ga2O3 films and demonstrated to own excellent electrical properties and stability. Au electrodes fabricated on the printed Ga2O3 and Cu-doped Ga2O3 layers showed good Ohmic behavior. Furthermore, high-power diodes are realized using printed p and n-type Ga2O3 homojunction through combining van der Waals stacking with transfer printing. The fabricated Ga2O3 homojunction diode exhibited good efficiency at room temperature, involving a rectification ratio of 103 and forward current density at 10 V (J@10 V) of 1.3 mA. This opens the opportunity for the cost-effective creation of semiconductor films with controlled metal dopants. The process disclosed here suggests important strategies for further synthesis and manufacturing routes in electronics industries. [ABSTRACT FROM AUTHOR]

Birefringence, which modulates the polarization of electromagnetic wave, has been commercially developed and widely used in modern photonics. Fostered by high-frequency signal processing and communications, feasible birefringence technologies operating in gigahertz (GHz) range are highly desired. Here, a coherent phonon-induced GHz optical birefringence and its manipulation in SrTiO3 (STO) crystals are demonsrated. With ultrafast laser pumping, the coherent acoustic phonons with low damping are created in the transducer/STO structures. A series of transducer layers are examined and the optimized one with relatively high photon-phonon conversion efficiency, i.e., semiconducting LaRhO3 film, is obtained. The most intriguing finding here is that, by virtue of high sensitivity to strain perturbation of STO, GHz optical birefringence can be induced by the coherent acoustic phonons and the birefringent amplitudes possess crystal orientation dependence. Optical manipulation of both coherent phonons and its induced GHz birefringence by double pump technique are also realized. These findings reveal an alternative mechanism of ultrafast optical birefringence control, and offer prospects for applications in high-frequency acoustic-optics devices. [ABSTRACT FROM AUTHOR]

To realize oxide semiconductor-based complementary circuits and better transparent display applications, the electrical properties of p-type oxide semiconductors and the performance improvement of p-type oxide thin-film transistors (TFTs) are required. In this study, we report the effects of post-UV/ozone (O3) treatment on the structural and electrical characteristics of copper oxide (CuO) semiconductor films and the TFT performance. The CuO semiconductor films were fabricated using copper (II) acetate hydrate as a precursor material to solution processing and the UV/O3 treatment was performed as a post-treatment after the CuO film was fabricated. During the post-UV/O3 treatment for up to 13 min, the solution-processed CuO films exhibited no meaningful change in the surface morphology. On the other hand, analysis of the Raman and X-ray photoemission spectra of solution-processed CuO films revealed that the post-UV/O3 treatment induced compressive stress in the film and increased the composition concentration of Cu–O lattice bonding. In the post-UV/O3-treated CuO semiconductor layer, the Hall mobility increased significantly to approximately 280 cm2 V−1 s−1, and the conductivity increased to approximately 4.57 × 10−2 Ω−1 cm−1. Post-UV/O3-treated CuO TFTs also showed improved electrical properties compared to those of untreated CuO TFTs. The field-effect mobility of the post-UV/O3-treated CuO TFT increased to approximately 6.61 × 10−3 cm−2 V−1 s−1, and the on-off current ratio increased to approximately 3.51 × 103. These improvements in the electrical characteristics of CuO films and CuO TFTs can be understood through the suppression of weak bonding and structural defects between Cu and O bonds after post-UV/O3 treatment. The result demonstrates that the post-UV/O3 treatment can be a viable method to improve the performance of p-type oxide TFTs. [ABSTRACT FROM AUTHOR]

The electrohydrodynamic (EHD) printing method shows advantages of solution-processed fabrication, low cost, and large area deposition in the construction of semiconductor films. Here, a layer and wide bandgap semiconductor lead iodide (PbI2) has been explored and studied by the EHD printing technique. The technique parameters, including solution density, electric field, and printing distance are explored and discussed in detail. A uniform, compact, and pin-hole-free PbI2 film is successfully fabricated. The photodetector constructed on this high-quality PbI2 active layer exhibits excellent photo-response performance. A low dark current of 1.68 pA and an impressive high ON/OFF current ratio higher than 103 are obtained. At a low bias of 1 V, the device shows a responsivity of 685 µA W−1, detectivity of 2.0 × 108 Jones, and fast photo-response speed (rise and fall time of 45 and 49 ms), respectively. These results are comparable with the reported works, which suggests that the EHD printing is a potential way of fabricating high-quality semiconductor film and high-performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

In our work, the model of self-consistent electron–deformation–diffusion effects in thin films grown on substrate with the mismatch of lattice parameters of the contacting materials is constructed. The proposed theory self-consistently takes into account the interaction of the elastic field (created by the mismatch of lattice parameters of the film and the substrate, and point defects) with the diffusion processes of point defects and the electron subsystem of semiconductor film. Within the framework of the developed model, the spatial distribution of deformation, concentration of defects, conduction electrons and electric field intensity is investigated, depending on the value of the mismatch, the type of defects, the average concentrations of point defects and conduction electrons. It is established that the coordinate dependence of deformation and the concentration profile of defects of the type of stretching (compression) centers, along the axis of growth of the strained film, have a non-monotonic character with minima (maxima), the positions of which are determined by the average concentration of point defects. It is shown that due to the electron–deformation interaction in film with a lattice parameter mismatch, the spatial redistribution of conduction electrons is observed and n-n+ transitions can occur. Information about the self-consistent spatial redistribution of point defects, electrons and deformation of the crystal lattice in semiconductor materials is necessary for understanding the problems of their stability and degradation of nano-optoelectronic devices operating under conditions of intense irradiation. [ABSTRACT FROM AUTHOR]

Birefringence, which modulates the polarization of electromagnetic wave, has been commercially developed and widely used in modern photonics. Fostered by high-frequency signal processing and communications, feasible birefringence technologies operating in gigahertz (GHz) range are highly desired. Here, a coherent phonon-induced GHz optical birefringence and its manipulation in SrTiO3 (STO) crystals are demonsrated. With ultrafast laser pumping, the coherent acoustic phonons with low damping are created in the transducer/STO structures. A series of transducer layers are examined and the optimized one with relatively high photon-phonon conversion efficiency, i.e., semiconducting LaRhO3 film, is obtained. The most intriguing finding here is that, by virtue of high sensitivity to strain perturbation of STO, GHz optical birefringence can be induced by the coherent acoustic phonons and the birefringent amplitudes possess crystal orientation dependence. Optical manipulation of both coherent phonons and its induced GHz birefringence by double pump technique are also realized. These findings reveal an alternative mechanism of ultrafast optical birefringence control, and offer prospects for applications in high-frequency acoustic-optics devices. [ABSTRACT FROM AUTHOR]

The development of high-precision large-area optical coatings and devices comprising low-dimensional materials hinges on scalable solution-based manufacturability with control over exfoliation procedure-dependent effects. As such, it is critical to understand the influence of technique-induced transition metal dichalcogenide (TMDC) optical properties that impact the design, performance, and integration of advanced optical coatings and devices. Here, we examine the optical properties of semiconducting MoS2 films from the exfoliation formulations of four prominent approaches: solvent-mediated exfoliation, chemical exfoliation with phase reconversion, redox exfoliation, and native redox exfoliation. The resulting MoS2 films exhibit distinct refractive indices (n), extinction coefficients (k), dielectric functions (ε1 and ε2), and absorption coefficients (α). For example, a large index contrast of Δn ≈ 2.3 is observed. These exfoliation procedures and related chemistries produce different exfoliated flake dimensions, chemical impurities, carrier doping, and lattice strain that influence the resulting optical properties. First-principles calculations further confirm the impact of lattice defects and doping characteristics on MoS2 optical properties. Overall, incomplete phase reconfiguration (from 1T to mixed crystalline 2H and amorphous phases), lattice vacancies, intraflake strain, and Mo oxidation largely contribute to the observed differences in the reported MoS2 optical properties. These findings highlight the need for controlled technique-induced effects as well as the opportunity for continued development of, and improvement to, liquid phase exfoliation methodologies. Such chemical and processing-induced effects present compelling routes to engineer exfoliated TMDC optical properties toward the development of next-generation high-performance mirrors, narrow bandpass filters, and wavelength-tailored absorbers. [ABSTRACT FROM AUTHOR]

With the advancement of the Internet of Things (IoT), numerous electronic devices are connected to each other and exchange a vast amount of data via the Internet. As the number of connected devices increases, security concerns have become more significant. As one of the potential solutions for security issues, hardware intrinsic physical unclonable functions (PUFs) are emerging semiconductor devices that exploit inherent randomness generated during the manufacturing process. The unclonable security key generated from PUF can address the inherent limitations of conventional electronic systems which depend solely on software. Although numerous PUFs based on the emerging memory devices requiring switching operations have been proposed, achieving hardware intrinsic PUF with low power consumption remains a key challenge. Here, we demonstrate that the process-induced nonlinear conductance variations of oxide semiconductor-based Schottky diodes provide a suitable source of entropy for the implementation of PUF without switching operation. Using a mild oxygen plasma treatment, the surface electron accumulation layer that forms naturally in oxide semiconductor film can be partially eliminated, resulting in a large variation of nonlinearity as an exotic entropy source. The mild plasma-treated Schottky diodes showed near ideal 50% average uniformity and uniqueness, as well as an ideal entropy value without the need for additional hardware area and power costs. These findings will pave the way for the development of hardware intrinsic PUFs to realize energy-efficient cryptographic hardware. [ABSTRACT FROM AUTHOR]

This work reports the fabrication of titanium dioxide (TiO2) nanoparticle (NPs) films using a scalable drop-casting method followed by ultra-violet (UV) irradiation for creating defective oxygen vacancies on the surface of a fabricated TiO2 semiconductor film using an UV lamp with a wavelength oof 255 nm for 3 h. The success of the use of the proposed scalable strategy to fabricate oxygen-vacancy-rich TiO2 films was assessed through UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The Ti 2p XPS spectra acquired from the UV-treated sample showed the presence of additional Ti3+ ions compared with the untreated sample, which contained only Ti4+ ions. The band gap of the untreated TiO2 film was reduced from 3.2 to 2.95 eV after UV exposure due to the created oxygen vacancies, as evident from the presence of Ti3+ ions. Radiation exposure has no significant influence on sample morphology and peak pattern, as revealed by the SEM and XRD analyses, respectively. Furthermore, the photocatalytic activity of the fabricated TiO2 films for methylene-blue-dye removal was found to be 99% for the UV-treated TiO2 films and compared with untreated TiO2 film, which demonstrated only 77% at the same operating conditions under natural-sunlight irradiation. The proposed UV-radiation method of oxygen vacancy has the potential to promote the wider application of photo-catalytic TiO2 semiconductor films under visible-light irradiation for solving many environmental and energy-crisis challenges for many industrial and technological applications. [ABSTRACT FROM AUTHOR]

A model has been proposed to describe the laser generation of two-dimensional semiconductor films with near-field pumping by quasitrapped modes excited in dielectric metasurfaces. A metastructure consisting of a Si metasurface coated with a MoTe2 film, where narrow-band resonance of a quasitrapped mode is joined with a broad exciton resonance of a two-dimensional material, has been designed. Threshold conditions for generation in the MoTe2 film with pumping by quasitrapped modes have been determined. The possibility of polarization control of the emission of the proposed metastructure has been demonstrated. [ABSTRACT FROM AUTHOR]

In this work, the synthesis of undoped and Sn-doped ZnO nanowires using vapor transport technique is reported. The effects of Sn content on morphological, structural, optical, electrical and sensing characteristics of ZnO nanowire films were examined by utilizing various techniques. X-ray diffraction inferred that all undoped and Sn-doped ZnO films are indexed to single hexagonal phase and no additional phases for tin or tin oxides were presented. The estimated Sn at.% rations was proportionate with the Sn ratios utilized in the source ingots. The morphology of the undoped ZnO sample was nanowires with quite long and smooth surfaces. After Sn doping, the smoothness of the nanowires is reduced and agglomerations of particles are observed. A reduction in transmittance and an increase in reflectance were observed after Sn doping. The optical band gap reduced from 3.27 to 3.06 eV with the elevation of Sn doping percent from 0 to 7 at.%. Two characteristic emission peaks were seen in the spectra around 388 nm and 540 nm. The emission peaks were affected by the Sn doping ratio. All the nanowires films demonstrated the semiconductor type manner with two distinct activation energies. The Sn doping enhanced the sensitivity of the sensors toward NO2 gas. [ABSTRACT FROM AUTHOR]

Pressure sensors based on field-effect transistor mechanism has received a lot of attention from researchers, which can effectively suppress low contrast and crosstalk effects. In this paper, we demonstrate a pressure sensor based on carbon nanotube field-effect transistor (CNTs-FET) and three-dimensional conformal force-sensitive top electrode with high sensitivity and easy integration. The high mobility field-effect transistor sensors were prepared using CNTs films with 99.9999% semiconductor concentration as the channel material. Conformal graphene nanowalls (GNWs) film on pyramidal micro-structure arrays worked as force-sensitive top electrode, the field-effect transistor sensor shows a sensitivity of 946.23 kPa−1 and 43.79 kPa−1 in the linear range of 0–30 Pa and 0.03–10 kPa, much higher than piezoresistive sensor (the sensitivity of about 377.73 kPa−1) and capacitive sensor (the sensitivity of 115.78 kPa−1). And the sensitivity and range of the sensor can be adjusted by the force-sensitive layer orientation design. Additionally, the sensor's response time is less than 30 ms, the recovery time is about 30 ms. The field-effect pressure sensor could detect ultra-low pressure (about 1.3 mg) of the chrysanthemum petals, and also could record the dynamic crawling process of the insect. [Display omitted] [ABSTRACT FROM AUTHOR]

Zinc oxide and titanium dioxide semiconductor photocatalysts have been widely utilized in the last few decades for water treatment because of their high photocatalytic efficiency. Recently, a lot of researchers have focused on the improvement of the photocatalytic properties of catalysts through modifying and co-modifying them with different metals and nonmetals. These co-catalytic ions improve the photocatalytic activity of ZnO and TiO2 by reducing its energy band gap. This might be useful in wastewater treatment for the photocatalytic degradation of organic contaminants. In this study, we prepared semiconductor films that were surface-modified with Ag co-catalyst layers via the photo-fixation of Ag (I) ions with varied concentrations (10−2–10−4 M) in the water phase under UV illumination for the first time. The photocatalytic behavior was evaluated by the degradation of malachite green and methylene blue under UV and visible light irradiation. The ZnO/Ag and TiO2/Ag samples showed a faster degradation of malachite green compared to methylene blue due to the formation of stable intermediates by the reaction of OH radicals with the triarylmethane dye (C=C bond) during the photocatalysis. The co-catalytic-silver-modified films had a higher photocatalytic efficiency in comparison with the pure nanostructures. The dye photodegradation rate constants increased in the following order: pure films < films modified with Ag, 10−4 M < films modified with Ag10−3 M < films modified with Ag10−2 M. The Ag modification and the heterojunction of the composites contributed to trapping and transfer of the electrons. Therefore, the photogenerated charges had a longer lifetime, resulting in a strengthened photocatalytic ability of the ZnO/Ag and TiO2/Ag films. [ABSTRACT FROM AUTHOR]

Effect of spin-orbit-induced (SOI) field on magnetization reversal in ferromagnetic semiconductor GaMnAs films with 4-fold in-plane magnetic anisotropy has been investigated by planar Hall resistance (PHR) and anisotropic magnetoresistance (AMR) with current along the <110> and <100> crystallographic directions, respectively. Field scan hysteresis of PHR and AMR measured with current of 2.5 mA were observed to be asymmetric respect to zero field, showing different transition fields between positive and negative field regions. In addition, the hysteresis asymmetry is reversed as the sign of the current is reversed from positive to negative. Such dependence of asymmetry on current polarity implies that the current-induced spin-orbit field, which is known to depend on the current direction, significantly affects magnetization reversal. The asymmetry observed for currents along [100], [010], [110], and [ 1 1 ̄ 0 ] crystallographic directions is fully consistent with the effects arising from the Dresselhaus-type SOI fields in GaMnAs films. [ABSTRACT FROM AUTHOR]

Ti-doped ZnO (TZO) and Bi2O3 thin films were designed and deposited by magnetron sputtering successively on ITO glass substrate to form a Ti-doped ZnO/Bi2O3 (TZO/Bi2O3) heterojunction. Microstructure and photoelectric properties of TZO, Bi2O3, and TZO/Bi2O3 films were tested and characterized. The results showed that TZO film with a hexagonal wurtzite structure was preferentially grown along the crystal plane (002), had a good crystallization state, and was an N-type semiconductor film with high transmittance (90%) and low resistivity (4.68 × 10−3 Ω·cm). However, the Bi2O3 film sputtered in an oxygen-containing atmosphere and was a polycrystalline film that was preferentially grown along the crystal plane (111). It had a lower crystallization quality than TZO film and was a P-type semiconductor film with low transmittance (68%) and high resistance (1.71 × 102 Ω·cm). The I–V curve of TZO/Bi2O3 composite films showed that it had an obvious heterojunction rectification effect, which indicates that the PN heterojunction successfully formed in TZO/Bi2O3 films. [ABSTRACT FROM AUTHOR]

Two main TCO materials were at the origin of this advent, tin oxide (SnO SB 2 sb ) and, especially, tin-doped indium oxide (In SB 2 sb O SB 3 sb : Sn or ITO). There are many areas of application in everyday life where a thin film (from a few nanometers to a few micrometers) of conductive or semiconductive oxide substantially modifies the chemical, optical, electrical, thermal, catalytic, mechanical and surface properties of the substrate it covers. The wide range of TCOs include different metal oxides, involving one or more atoms of a metal of different metals and oxygen atoms, hence the name TCO. [Extracted from the article]

There have been many reports on room-temperature ferromagnetism (RTFM), which is often observed in pure semiconductor nanoparticles without transition metal elements. Because RTFM tends to be found in semiconducting thin films or nanoparticles, the origin of ferromagnetism is believed to result from the specific surface structure or defects on the surface. However, there is no direct evidence for such surface phenomena, and the relationship between RTFM and physical properties reported in the bulk state must be investigated. If RTFM is independent of the bulk properties, then it is concluded to be a surface phenomenon. In this study, VO2 nanoparticles with metal–insulator transitions (MITs) are evaluated. Magnetic field dependences of the magnetization of VO2 nanoparticles confirmed with MITs indicate a small amount of hysteresis before and after the transition temperature. This indicates that RTFM is independent of the particle's core properties, and ferromagnetic order is concluded to occur only on the surface. [ABSTRACT FROM AUTHOR]

There have been many reports on room-temperature ferromagnetism (RTFM), which is often observed in pure semiconductor nanoparticles without transition metal elements. Because RTFM tends to be found in semiconducting thin films or nanoparticles, the origin of ferromagnetism is believed to result from the specific surface structure or defects on the surface. However, there is no direct evidence for such surface phenomena, and the relationship between RTFM and physical properties reported in the bulk state must be investigated. If RTFM is independent of the bulk properties, then it is concluded to be a surface phenomenon. In this study, VO2 nanoparticles with metal–insulator transitions (MITs) are evaluated. Magnetic field dependences of the magnetization of VO2 nanoparticles confirmed with MITs indicate a small amount of hysteresis before and after the transition temperature. This indicates that RTFM is independent of the particle's core properties, and ferromagnetic order is concluded to occur only on the surface. [ABSTRACT FROM AUTHOR]

The simulation of the process of heat propagation in the NbN film during the passage of a current pulse through it was carried out on the basis of an inhomogeneous two-dimensional equation of heat conduction. The initial-boundary value problem for longitudinal section of the film is solved numerically, and the analysis of heat transport in the system contacts-film-substrate-thermostat is carried out. The temperature evolution of the film cross section from the onset of the pulse to temperature leveling is visualized. It is shown that the contact material (beryllium bronze) provides efficient heat removal from a superconducting film in a resistive state when a high-density current flows through it. The proposed modeling method and contact material can be used to study other metal or semiconductor films. [ABSTRACT FROM AUTHOR]

The co-facially stacked dyes on semiconductor films serve as an alternative model to elucidate the photo-driven exciton dynamics occurring in a molecular assembly. In this study, we report the unique emission properties of coumarin dye adsorbed on the surface of the semiconductor film, measured by ultrafast time-resolved fluorescence. When a rigid coumarin derivative, 7-hydroxycoumarin-3-carboxylic acid (OHCCA), is anchored on the Al2O3 film, the dye manifests dual emissions from the two lowest excited states. Various anchoring modes of a carboxylic acid group on the Al2O3 surface are invoked to account for the unusual emission process. Additionally, we identified characteristic transition dipole interactions in the well-stacked dye aggregates, which leads to discernible excitonic splitting in the electronic transitions. Femtosecond time-resolved fluorescence reveals that the excimer formation in the aggregate occurs with the time constant of 550 fs. Picosecond time-resolved emission spectra confirm the subsequent structural relaxations of the nascent excimer. The enhanced transition dipole via the electronic coupling between OHCCA and metal oxide can be responsible for the dual emission and the ultrafast excimer formation. [ABSTRACT FROM AUTHOR]

The formation of oxide semiconductor films of the (Mn,Co,Cu)3O4 type by radio frequency magnetron sputtering is presented. The conditions of deposition and subsequent heat treatment make it possible to obtain films with electrophysical characteristics close to those of the bulk ceramic materials used as a target for magnetron sputtering. Two variants of thermistor geometry were implemented. In the first case, the working layer of oxide semiconductor was deposited directly on the dielectric substrate (planar geometry), and in the second case on the layer with high electrical conductivity (Ni or Al) forming the inner electrode (layered geometry). The lower limit of the nominal resistance of the planar thermistor while maintaining high temperature nonlinearity is ~ 10 kΩ. The layered structure with the inner electrode makes it possible to reduce the lower limit of resistance up to ~ 50 Ω without losing the temperature nonlinearity of the thermistor. In addition, heat treatment above 450 °C or current self-heating with sufficient power output leads to the appearance of a pronounced voltage nonlinearity, which increases the thermal constant B of thermistors from 2400–3400 to 5000–5500 K. The fields of application of oxide-film structures for the correction of linear resistors and the implementation of integration approaches in the construction of linearized sensors are discussed. [ABSTRACT FROM AUTHOR]

This work presents the analytical physical modeling of undoped organic metal‐electrolyte‐semiconductor (OMES) capacitors in the framework of the Nernst–Planck–Poisson theory, including the presence of compact interfacial layers. This work derives an exact analytical solution, up to a quadrature, for the stationary electric potential and charge density distributions in both the semiconductor film and the electrolyte solution, and from them the sheet semiconductor charge and the stationary differential capacitance are obtained as a function of the applied voltage. The dependence of these magnitudes on the physical device parameters, like the ionic concentration of the electrolyte, the capacitance of the interfacial compact layers and the injected hole density is then analyzed. This work shows that ionic diffusive effects in the electrolyte can play an important role in the device response, inducing a broadening of the transition from the weak to the strong accumulation regimes. This fact can make that the strong accumulation regime is not achieved in OMES within the usual voltage operation range of these devices. The analytical solution is validated by means of finite element numerical calculations. The implications of the results obtained on the physics of electrolyte gated organic field effect transistors (EGOFETs) are discussed. [ABSTRACT FROM AUTHOR]

A silver sulfide (Ag2S) semiconductor photocatalyst film has been successfully synthesized using a solution casting method. To produce the photocatalyst films, two types of Ag2S powder were used: a commercialized and synthesized powder. For the commercialized powder (CF/comAg2S), the Ag2S underwent a rarefaction process to reduce its crystallite size from 52 nm to 10 nm, followed by incorporation into microcrystalline cellulose using a solution casting method under the presence of an alkaline/urea solution. A similar process was applied to the synthesized Ag2S powder (CF/syntAg2S), resulting from the co-precipitation process of silver nitrate (AgNO3) and thiourea. The prepared photocatalyst films and their photocatalytic efficiency were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-visible spectroscopy (UV-Vis). The results showed that the incorporation of the Ag2S powder into the cellulose films could reduce the peak intensity of the oxygen-containing functional group, which indicated the formation of a composite film. The study of the crystal structure confirmed that all of the as-prepared samples featured a monoclinic acanthite Ag2S structure with space group P21/C. It was found that the degradation rate of the methylene blue dye reached 100% within 2 h under sunlight exposure when using CF/comAg2S and 98.6% for the CF/syntAg2S photocatalyst film, and only 48.1% for the bare Ag2S powder. For the non-exposure sunlight samples, the degradation rate of only 33–35% indicated the importance of the semiconductor near-infrared (NIR) Ag2S photocatalyst used. [ABSTRACT FROM AUTHOR]

Microactuators that convert external stimuli such as heat, light, current, and magnetic field into mechanical motion are essential components in microelectro‐mechanical systems. To date, microactuators have been fabricated mainly using conventional microfabrication technologies and inorganic thin films, but although such technologies facilitate the mass production of microdevices, they are expensive and lack flexibility when either preparing only a few devices or facing special needs. Laser‐direct‐writing is an effective complement to microfabrication, but is seldom used in the construction of inorganic microactuators. In this work, a laser‐direct‐writing technique on the freestanding vanadium dioxide (VO2) film for fabricating microactuators with arbitrary shapes is developed. The precision of the laser direct writing attained 2 µm under ultralow pulse energy of 52 pJ. The pulse energy is two orders of magnitude lower than that needed for patterning VO2 film and other semiconductor materials on substrates. The overall performance of the resulting VO2 microactuators is comparable with that of those fabricated by conventional microfabrication technologies, but the fabricating efficiency and flexibility are increased. Such a fabrication strategy can also be used to fabricate other smart microdevices, such as strain sensors and photodetectors. [ABSTRACT FROM AUTHOR]

Organic field‐effect transistors (OFETs) with low‐voltage‐operating high‐stability are regarded as one of the key components of future electronics. However, it remains a challenge to enhance bias–stress stability, mechanical durability and environmental adaptability while reducing the operating voltage of the flexible OFETs. In this study, a new strategy of introducing high‐dipole‐moment groups into polymer side chains to enhance the intensity of polarization was proposed. This strategy can redirect cyclic carbonate side chains of high‐dipole groups under the action of electric fields and realize stable operation and efficient charge transfer. The experiments showed that high‐performance flexible OFETs were mainly attributed to the synthesized polymers through molecular structure designing which not only have high dielectric constant (k > 5) and high electrical insulating property but also favor the growth of organic semiconductor films. The flexible OFETs still showed excellent mechanical flexibility, high electrical, thermal and humidity stability. In addition, highly OFETs were applied into a floating‐gate memory with fullerene (C60) embedded charge memory layer and an integrated one‐transistor‐one‐transistor memory cell. They exhibited excellent memory performance with a large memory window (8.5 V), current ratio (103), stable retention (2 × 104 s), cyclic endurance (200 cycles), multi‐level memory (over 4 levels) and non‐destructivity. [ABSTRACT FROM AUTHOR]

Highlights: What are the main findings? There is a threshold thickness and incident angle below which the film is unaffected by the shadow effect during DC magnetron sputtering. The later-deposited film causes the earlier-deposited film to be affected by the shadow effect. The shadow effect manifests earlier for films deposited on the insulator SiO2 than for those deposited on the semiconductor Si. What is the implication of the main finding? There is no need to worry about the shadow effect when the film deposited by oblique incident deposition has small thickness or the incident angle is small. The conductivity of the substrate could influence the shadow effect. When depositing films on a complex workpiece surface by magnetron sputtering, the shadow effect occurs and causes the columnar structure to tilt toward the substrate owing to the oblique incident angle of the plasma flux, affecting the microstructure and properties of the films. Improving the surface diffusion could alleviate the shadow effect, whereas changing the energy of the deposited particles could improve surface diffusion. Different substrate conductivities could affect the energy of the deposited particles when they reach the substrate. In this study, Si (semiconductor) and SiO2 (insulator) sheets are mounted on the inner surface of a hemispherical workpiece, and Ti films with different thicknesses (adjusted by the deposition time) are deposited on the inner surface of the hemispherical workpiece by direct current magnetron sputtering. The results show that there is a threshold thickness and incident angle before the films are affected by the shadow effect. The threshold could be affected by the film thickness, the incident angle, and the conductivity of the substrate. The threshold would decrease as the film thickness or incidence angle increased or the conductivity of the substrate decreased. When the film thickness or incident angle does not reach the threshold, the film would not be affected by the shadow effect. In addition, the film deposited later would tilt the vertical columnar structure of the film deposited earlier. Owing to the different conductivities, the shadow effect manifest earlier for Ti films deposited on the insulator SiO2 than for films deposited on the semiconductor Si when the film thickness is >500 nm. [ABSTRACT FROM AUTHOR]

The integration of photonics with electronics has been key to increasing the speed and total bandwidth of silicon-photonics-based assemblies, with several approaches being able to create transceivers with bandwidths of 1.6 Tbps and above. The application of thin-films as development direction of integrated electronics is based on the sequential build-up of films of various materials on a common base (substrate) with the simultaneous formation of micro-parts (resistors, capacitors, contact pads, etc.) and internal circuit connections from these films. The convergence of the advances in silicon photonics and electronics means that combined silicon photonics and electronics enable continued progress and drive further innovation in both fields. For nanohybrids of ZnO/graphene heterostructures, the low thermal budget for the growth of crystalline ZnO makes the direct deposition of ZnO onto graphene with a controlled morphology and surface possible. [Extracted from the article]

Dye-sensitized solar cells (DSSCs) were developed by exploiting the photovoltaic effect to convert solar energy into electrical energy. The photoanode layer thickness significantly affects the semiconductor film's ability to carry electronic charges, adsorb sensitizing dye molecules, and lower the recombination of photo-excited electrons injected into the semiconductor. This study investigated the dependence of the zinc oxide (ZnO) photoanode thin-film thickness and the film soaking time in N719 dye on the photocurrent–voltage characteristics. The ZnO photoanode was applied to glass using the doctor blade method. The thickness was varied by changing the scotch tape layers. The ZnO-based DSSC attained an efficiency of 2.77% with three-layered photoanodes soaked in the dye for three hours, compared to a maximum efficiency of 0.68% that was achieved with three cycles using the dip-coating method in other research. The layer thickness of the ZnO photoanode and its optimal adsorption time for the dye are important parameters that determine the efficiency of the DSSC. Therefore, this work provides important insights to further improve the performance of DSSCs. [ABSTRACT FROM AUTHOR]

We fabricated nanocrystalline Ge films using radio-frequency (RF) magnetron plasma sputtering deposition under a high Ar-gas pressure. The Ge nanograins changed from amorphous to crystalline when the distance between the Ge sputtering target and the substrate was decreased to 5 mm and the RF input power was 11.8 W/cm2 (60 W), where the deposition rate was as high as 660 nm/min. In addition, the size of the nanocrystalline grains increased from 100 to 307 nm when the RF input power for plasma production was increased from 11.8 W/cm2 (60 W) to 17.7 W/cm2 (90 W). In the developed narrow-gap plasma process at sub-Torr pressures, nanocrystalline Ge films were successfully fabricated on Cu substrates at low temperatures, without the substrate being heated. However, when annealing was conducted under an N2 atmosphere, which is the conventional method to induce solid-phase crystallization, the amorphous Ge layer on a Cu substrate changed to a Cu3Ge crystal layer through interdiffusion of Ge and Cu atoms at 400–500 °C.

The article discusses the use of organic semiconductors in electronic devices such as transistors, OLEDs, and solar cells. It explains that high charge-carrier mobility is important for device performance and can be achieved through the design of specific chemical compositions and nano-morphologies. The article also explores different strategies to enhance charge-carrier mobility in soluble organic semiconductors, including modifying conjugated molecules with side chains and using polymers. The Hall effect is described as an effective tool for studying electron transport in semiconductors, and a recent study on solution-processed perylene diimide films is highlighted, which showed evidence of band-like transport and high Hall mobility. The findings suggest new possibilities for designing high-mobility semiconductors and improving charge-carrier transport in conjugated polymer films. [Extracted from the article]

The article presents a study which explores about mechanically robust stretchable semiconductor metallization for skin-inspired organic transistors. It report a highly stretchable and robust metallization on an elastomeric semiconductor film based on metal-elastic semiconductor intermixing. It mentions the challenges in the development of stretchable metallization.

We demonstrate the acoustic charge transport of optically induced excitons in two organic semiconductors, P3HT and MEH-PPV, up to a distance of 3 mm. The device consists of a surface acoustic wave (SAW) resonator transmitting SAW through a polymer layer where acoustic charge transport takes place and a polymer diode at the end to collect the charges. The voltage excitation is provided using an interdigital transducer (IDT) on a piezoelectric YZ lithium niobate substrate producing Rayleigh SAW at 42 MHz. Optical illumination up to 15 mW cmâˆ'2 intensity is applied to induce excitons in the polymer layer deposited on the lithium niobate substrate. The photogenerated excitons in the polymer are ionized by SAW field resulting in free carriers that are transported to the polymer diode by the travelling SAW. A surge in photovoltaic current in the diode is observed in the presence of SAW when the carriers are optically generated away from the diode. The maximum charge capacity and transfer efficiency of the acoustic transport are calculated for various SAW power and illumination intensities. A theoretical analysis of charge carrier dynamics in the presence of a moving SAW field is also performed using a semi-classical Hamiltonian of the system. [ABSTRACT FROM AUTHOR]

The present work aims to predict the elastic constants and other significant properties of ordered BxAl1-xSb (0 = x = 1) ternary semiconducting alloys. We report the initial results of the elastic stiffness constants, the bulk modulus, the aggregate shear modulus, the Cauchy ratio, the aggregate Young's modulus, the Born ratio, the isotropy factor, the fracture toughness and the longitudinal, transverse and average sound velocities. The Debye temperature and the melting point were also predicted using two different empirical expressions. Except the Cauchy ratio, which decreases with enhancing boron content x, all other physical quantities of BxAl1-xSb alloys increase gradually and monotonically with increasing of boron concentration x in the range 0-1. Our obtained data for BSb and AlSb binary semiconducting compounds are discussed and analyzed in comparison with experimental and other theoretical values of the literature. Generally, our data for BSb and AlSb are in good agreement with other results reported previously in literature. Indeed, our obtained value (335.82 K) of the Debye temperature for AlSb compound overestimates the result (328.6 K) reported by Salehi et al. by around 2.03%, while that (1520 K) of the melting point for BSb overestimates the result (1500 K) reported recently by Bioud et al. by around 1.34%. Furthermore, to the best of our knowledge, no theoretical or experimental data were reported in the literature on the elastic constants and other properties for BxAl1-xSb alloys to compare with them. [ABSTRACT FROM AUTHOR]