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Alkylated benzothienobenzothiophenes are an important class of organic semiconductors that exhibit high performance in solution-processed organic field-effect transistors. In this work, we study the near-edge x-ray absorption fine-structure (NEXAFS) spectra of 2,7-didecyl[1]benzothieno[3,2-b][1]benzothiophene (C10-BTBT) at both the carbon and sulfur K-edges. Angle-resolved experiments of thin films are performed to characterize the dichroism associated with molecular orientation. First-principles calculations using the density functional theory-based many-body x-ray absorption spectroscopy (MBXAS) method are also performed to correlate the peaks observed and their dichroism with transitions to specific antibonding molecular orbitals. Interestingly, the dichroism of the dominant, lowest energy peak is opposite at the carbon and sulfur K-edges. While the low-energy peak at the carbon K-edge is assigned to carbon 1s → π* transitions with transition dipole moment (TDM) perpendicular to the planar BTBT core, the dominant low energy peak at the sulfur K-edge is assigned to sulfur 1s → σ* transitions with TDM oriented along the long axis of the BTBT core. These differences at the sulfur and carbon K-edges are understood through the MBAXS simulations that find a reordering of the energy of the lowest energy π* and σ* transitions at the sulfur K-edge due to the strong localization of the σ* orbital over the sulfur atom. This work highlights differences in the NEXAFS spectra of organic semiconductors at carbon and sulfur K-edges and provides new insights into peak assignment and x-ray dichroism relevant for studying the molecular orientation of organic semiconductor films. [ABSTRACT FROM AUTHOR]

Action spectroscopies use a readout created by the action of light on the molecules or material rather than optical absorption. Ultrafast 2D photocurrent and 2D fluorescence spectroscopies are two such action spectroscopies. Despite their utility, multidimensional action spectroscopies suffer from a background created by incoherent population mixing. These backgrounds appear when the action of one molecule impacts that of another, creating a signal that mimics a fourth-order population response but is really just the convolution of two linear responses. The background created by incoherent mixing is often much larger than the desired foreground signals. In this paper, we describe the physical mechanisms that give rise to the incoherent signals, drawing Feynman paths for each. There are three variations of incoherent signals, differing by their pulse ordering. They all have the same phase dependence as the desired fourth-order population signals and so cannot be removed by standard phase cycling, but they do differ in their polarization responses and dephasing times. We propose, and implement, a spectrometer design that eliminates the background signals for isotropically oriented samples, leaving only the desired fourth-order 2D action spectra. Our spectrometer utilizes a TWINS interferometer and a pulse shaper interferometer, each driven with a different white-light source so that the pulse pairs within each interferometer are phase stable, but not between the two. The lack of phase stability between the two interferometers eliminates two of the three incoherent responses. The third incoherent response is eliminated with the polarization scheme ⟨0, π/2, π/4, π/4⟩. Our spectrometer also enables both 2D photocurrent and 2D white-light spectra to be collected simultaneously, thereby enabling a direct comparison between action and optical detection under identical conditions and at the exact same position on the sample. Using this spectrometer and photovoltaic devices made from thin films of semiconducting carbon nanotubes, we demonstrate 2D photocurrent spectra free of incoherent background. [ABSTRACT FROM AUTHOR]

Deposition of epitaxial oxide semiconductor films using physical vapor deposition methods requires a detailed understanding of the role of energetic particles to control and optimize the film properties. In the present study, Ga 2 O 3 thin films are heteroepitaxially grown on Al 2 O 3 (0001) substrates using oxygen ion beam sputter deposition. The influence of the following relevant process parameters on the properties of the thin films is investigated: substrate temperature, oxygen background pressure, energy of primary ions, ion beam current, and sputtering geometry. The kinetic energy distributions of ions in the film-forming flux are measured using an energy-selective mass spectrometer, and the resulting films are characterized regarding crystalline structure, microstructure, surface roughness, mass density, and growth rate. The energetic impact of film-forming particles on the thin film structure is analyzed, and a noticeable decrease in crystalline quality is observed above the average energy of film-forming Ga + ions around 40 eV for the films grown at a substrate temperature of 725 ° C. [ABSTRACT FROM AUTHOR]

The on-demand assembly of 2D heterostructures has brought about both novel interfacial physical chemistry and optoelectronic applications; however, existing studies rarely focus on the complementary part—the 2D cavity, which is a new-born area with unprecedented opportunities. In this study, we have investigated the electric field inside a spacer-free 2D cavity consisting of a monolayer semiconductor and a gold film substrate. We have directly captured the built-in electric field crossing a blinking 2D cavity using a Kelvin probe force microscopy–Raman system. The simultaneously recorded morphology (M), electric field (E), and optical spectroscopy (O) mapping profile unambiguously reveals dynamical fluctuations of the interfacial electric field under a constant cavity height. Moreover, we have also prepared non-blinking 2D cavities and analyzed the gap-dependent electric field evolution with a gradual heating procedure, which further enhances the maximum electric field exceeding 109 V/m. Our work has revealed substantial insights into the built-in electric field within a 2D cavity, which will benefit adventures in electric-field-dependent interfacial sciences and future applications of 2D chemical nanoreactors. [ABSTRACT FROM AUTHOR]

Cupric oxide (CuO) is a promising p-type semiconducting oxide used in many critical fields, such as energy conversion and storage, and gas sensors, which is attributed to its unique optoelectrical properties and cost-effectiveness. This work successfully deposited amorphous, pinhole-free, ultrathin CuO films using atmospheric pressure spatial atomic layer deposition (SALD) with copper(II) acetylacetonate and ozone as precursors. The growth rate increased from 0.05 Å/cycle at 175 °C to 0.35 Å per cycle at 275 °C. XPS and XRD confirmed the formation of a pure CuO phase, with typical strong satellite shake-up peaks, and a tenorite crystalline phase. The films exhibited semiconducting behavior, with temperature-dependent electrical measurements revealing the Fermi level positioned 0.2–0.24 eV above the valence band. Furthermore, p-type CuO was combined with n-type ZnO, both deposited by SALD, to form a high-performance photodiode. This CuO/ZnO heterojunction demonstrated excellent rectifying behavior, with an ION/IOFF ratio of 2.04 × 103, and functioned as an efficient UV detector, showing fast response and good repeatability. These results highlight the potential of SALD-deposited CuO thin films for optoelectronic applications. [ABSTRACT FROM AUTHOR]

In this study, the field‐effect generated by illuminated p‐type ferroelectric bismuth ferrite (BiFeO3 or BFO) semiconductor film is utilized to modulate the water‐splitting performance of a system with a macroscopic spatial separation between the anode and cathode. When the BFO film in contact with an electrolyte is illuminated with a light of sufficiently high frequency, an electrolytic conducting channel is formed due to the field effect induced by photoexcited charge carriers in the BFO film, which in turn alters the water‐splitting pathway and the reaction mechanism. The field effect can be modulated by changing the orientation of the ferroelectric polarization in the BFO film. With a BFO film of 4.5 mm channel length and an overall upward ferroelectric polarization direction, a ∼30% increase in water‐splitting performance in a neutral‐pH electrolyte is achieved in the presence of field‐effect induced by a 20 mW 405 nm light source. The mechanism behind the field‐effect modulation is also further verified by monitoring the pH of the electrolyte during the water‐splitting process and conducting thresholding analysis on the recorded data. The field‐effect modulation described in this study can potentially be used to enhance the performance of a photoelectrochemical water‐splitting system by taking advantage of the presence of light illumination in the system or be utilized in electrochemical sensing applications. [ABSTRACT FROM AUTHOR]

In this study, Cadmium Oxide (CdO) semiconductor films with different iron (Fe) and cobalt (Co) concentrations have been produced at 350 °C substrate temperature on the glass substrates by the ultrasonic spray pyrolysis method. In the first part of this study, the Fe element was doped in different ratios (2, 4, 6%) to CdO films, and the films were characterized. At the end of this stage, the optimum Fe doping ratio was determined for CdO films. In the second step, CdO films were dually doped with Fe + Co. The electrical resistivities of CdO:Fe films were determined using a four-probe technique to measure their conductivities, carrier concentrations, mobilities, and electrical conductivity types through Hall measurements. The produced films showed n-type electrical conductivity. It was determined that with increasing doping ratios, the electrical resistivity generally increased, and the films exhibited n-type conductivity. The XRD patterns revealed that the crystal structures of the films were polycrystalline and cubic in structure. The lections of (111), (200), (220), (311), and (222) planes were observed in the XRD patterns. Upon examination of the SEM images, it was observed that the films had nearly homogeneous surfaces and good adhesion to the substrate. By utilizing the fundamental absorption spectra of the films, it was determined that they exhibited direct bandgap transitions, and the bandgap energy values ranged from 2.34 to 2.65 eV. In the structural analysis, all films were found to have a polycrystalline structure and cubic CdO crystal system. When the SEM images of CdO:(Fe + Co) films were examined, it was observed that the films had almost homogeneous surfaces. Based on all these analyses, it was concluded that the doping elements Fe and Co significantly influenced the physical properties of CdO thin films. [ABSTRACT FROM AUTHOR]

Charge carrier transportation in semiconductor films is a fundamental but crucial process for the light-emitting diodes. Although there have been many studies on charge transport properties of devices based on traditional inorganic crystals and organic amorphous films, such charge behavior within emerging quantum-dot light-emitting diodes (QLEDs)—which are composed of amorphous nanocrystal films with strong quantum confinement effects—has rarely been discussed. Here, we demonstrate that the tunneling effect really occurs in the hybrid QLEDs with ZnO as the electron-transport layer. By suppressing the thermal effect, a negative differential resistance (NDR) phenomenon is observed by decreasing the working temperature of the QLED low to 150 K. Two types of quantum dots (QDs) with different shell structures (i.e., different tunneling barrier) are used to comparatively examine the tunneling effect. The current density–voltage properties of the QLEDs reveal that the device based on QDs with the sharp core-shell structure (i.e., larger tunneling barrier) exhibits more obvious NDR behavior, which is attributed to the stronger tunneling effect. Our results offer significant insight into the charge dynamics and working mechanism in the QLEDs. [ABSTRACT FROM AUTHOR]

In this work, we present the green synthesis of complex A–E derived from β-hidroxymethylidene indanones by ultrasound, which allowed for the obtaining of compounds in a shorter time and with good yields. These organotin complexes were then doped with cobalt porphine and incorporated into a poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) matrix to manufacture composite semiconductor films. The semiconductor films were characterized through atomic force microscopy, examining their topography, Knoop hardness (around 17 HK), and tensile strength, which varied from 5 × 10−4 to 7 × 10−2 Pa. The optical behavior was evaluated, revealing that the changes in these characteristics are related to the type of organotin complex present in the composite film: the transmittance ranged from 77% to 86%, while the reflectance varied from 13% to 17%. The band gap, calculated using the Kubelka–Munk function F(KM), was approximately 3.7 ± 0.19 eV for all the semiconductor films. Finally, we assessed the electrical behavior of the composite films through current–voltage (I–V) measurements under different lighting conditions. The I–V curves demonstrated that they share a saturation current density of 3.46 mA/mm2. However, they differ in their conduction rates within the ohmic regimen. These composite films' optical and electrical properties suggest their potential use in developing electronic devices like organic diodes. [ABSTRACT FROM AUTHOR]

In this study, bilayer MoS2 was synthesized on graphene film using chemical vapor deposition (CVD) to get a hetero‐film photo‐catalyst for the photo‐assisted charging of Li‐oxygen battery. The synthesized hetero‐film exhibited an optical band gap of 1.8 eV and a valence band edge potential of −1.23 VAg/AgCl (2.04 VLi+/Li). Fast‐responding photocurrents in the microampere range were achieved through on‐off cycles under visible‐light irradiation. The anodic nature of the photocurrents indicated that the synthesized semiconductor film was n‐type. Photo‐assisted testing demonstrated that the MoS2/graphene hetero‐film photo‐catalyst significantly reduced the charging potential and increased the discharging potential at a current density of 0.1 mA cm−2, thereby greatly enhancing the cyclic performance of the Li‐oxygen battery. [ABSTRACT FROM AUTHOR]

Ferroelectric semiconductors have the advantages of switchable polarization ferroelectric field regulation and semiconductor transport characteristics, which are highly promising in ferroelectric transistors and nonvolatile memory. However, it is difficult to prepare a Sn-based perovskite film with both robust ferroelectric and semiconductor properties. Here, by doping with 2-methylbenzimidazole, Sn-based perovskite [93.3 mol% (FA0.86Cs0.14)SnI3 and 6.7 mol% PEA2SnI4] semiconductor films are transformed into ferroelectric semiconductor films, owing to molecular reconfiguration. The reconfigured ferroelectric semiconductors exhibit a high remanent polarization (Pr) of 23.2 μC/cm2. The emergence of ferroelectricity can be ascribed to the hydrogen bond enhancement after imidazole molecular doping, and then the spatial symmetry breaks causing the positive and negative charge centers to become non-coincident. Remarkably, the transistors based on perovskite ferroelectric semiconductors have a low subthreshold swing of 67 mv/dec, which further substantiates the superiority of introducing ferroelectricity. This work has developed a method to realize Sn-based ferroelectric semiconductor films for electronic device applications. The authors observe the emergence of ferroelectricity in Sn-based perovskite [93.3 mol% (FA0.86Cs0.14)SnI3 and 6.7 mol% PEA2SnI4] semiconductor films doped with 2-methylbenzimidazole, ascribing to the hydrogen bond enhancement after imidazole molecular doping. [ABSTRACT FROM AUTHOR]

Scheme 1. Schematic illustration of the fabrication of patterned reduced sericin coating after UV irradiation and the application for patterned composite coating, fluorescent pattern and superhydrophobic coating. [Display omitted] • The novel and green reduced sericin film was prepared for fabricating precise patterns via water-base lithography. • The biocompatible reduced sericin film as a functional template to support cell attachment, entrap fluorescent blocks (DSAI), cell and fluorescent strip patterns has been presented. • The stable reduced sericin film as a resist to fabricate chemical etching pattern has been presented, exhibiting its application in structure-induced color and superhydrophobic coating. The use of toxic resists and complex procedures has impeded the resolution and quality of micro/nanofabrication on virtually arbitrary substrates via photolithography. To fabricate a precise and high-resolution pattern, a sericin nanofilm-based coating was developed by reducing disulfide bonds and subsequently assembling sericin protein. Upon exposure to ultraviolet (UV) light, intermolecular amide bonds in sericin are cleaved through the action of a reducing agent, allowing the reduced sericin (rSer) coating to exhibit the functional ability to generate diverse geometric micro/nanopatterns through photomask-governed photolithography. The rSer film serves as a platform for the encapsulation of fluorescent molecules, enabling fluorescent micropatterns applicable in anti-counterfeiting and encryption. In addition, the patterned rSer nanofilms support biocompatible cell proliferation. With their excellent chemical stability, high-resolution geometric patterns can be transferred onto silicon substrates through chemical etching, resulting in periodic chemical etching patterns that display structural colours. Inspired by the micro/nanostructures of lotus leaves, elliptical microstructures exhibit superhydrophobic behaviour, highlighting the versatility of the rSer film for applications in semiconductors, anti-counterfeiting, smart displays, and superhydrophobic coatings. [ABSTRACT FROM AUTHOR]

In aviation and space applications, sensors have a significant effect in determining the effect of toxic gases at human contact points. Therefore, in this study, gas sensor applications of ZnO films are suggested in order to understand the effects of many different gases in the field of aviation and space without harming humans. This study systematically describes the synthesis and characterization of ZnO semiconductor films on glass substrate for gas sensors to be used in aerospace applications. These coatings were successfully synthesized on glass substrates using the sol-gel technique. In this process, transparent solutions were prepared using different concentrations of Zn acetate, methanol and glacial acetic acid. In addition to the thermal and structural properties, it was found that the film prepared from the solution containing low concentration Zn with 12g methanol had a crack-free, pinhole-free and continuous surface, and the surface roughness and cracks in the films increased with increasing number of layers. It is recommended to use ZnO-based gas sensors at room temperature inside the aircraft where exposure to toxic gases may occur, and at elevated temperatures close to the engine area, which may be important for thermal management and accident prevention. As a remarkable result of these studies, systematic correlations were established between solution conditions and film quality as innovative studies and it was determined that high quality ZnO film was produced by sol-gel method and contributed to its use in gas sensors in aviation applications. [ABSTRACT FROM AUTHOR]

Harnessing confined light on a subwavelength scale within Fano metasurfaces enhances light‐matter interaction on a flexible, low‐loss substrate. This approach enables the integration of ultra‐thin semiconducting films for designing low‐power, ultrafast switchable terahertz, and optical meta devices. Here, an ultra‐thin, ∼λ/6000 germanium overlayers of 25nm or 50nm is thermally evaporated onto a flexible Fano metallic metasurface to achieve ultrafast optical modulation of terahertz radiation. A remarkable 85% modulation depth with an ultrafast speed of 400 GHz is obtained in the resonant transmission. These ultrathin, flexible, and ultrafast functional metasurfaces pave the way for developing flexible terahertz active meta devices based on nanometric scale germanium films, offering the additional advantage of compatibility with complementary metal‐oxide‐semiconductor (CMOS) technology in microelectronics. [ABSTRACT FROM AUTHOR]

Engineering the dielectric constant (ε) to lower the exciton binding energy of the light‐absorbing semiconductor can improve organic photovoltaic (OPV) device performance. Here, a series of materials are reported with 2‐(3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐ylidene)malononitrile (INCN) acceptor end groups and a central glycolated bis(4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene) unit with large low‐frequency (εlf = 7.4–7.9 at 0.1–0.2 MHz) and optical‐frequency (εopt up to 6.6 at 2 × 1014 Hz) dielectric constants. The INCN end groups differed in whether they were protonated, chlorinated, or fluorinated, with the latter having the highest εopt. An εopt of 6.6 is predicted to lead to a low exciton binding energy of ≈0.04 eV. Time‐resolved microwave conductivity measurements showed a temperature‐dependent yield–mobility product, with it increasing linearly from 340 K. The onset temperature was near that required to overcome the calculated exciton binding energy and indicates increased free charge generation in a homojunction film. Room temperature transient absorption spectroscopy revealed that photoexcitation rapidly converted to a lower energy state that was consistent with the formation of polarons or a charge transfer state. This work provides experimental evidence of the importance of εopt for the generation of free charges, and a strategy for development of efficient single chromophore homojunction OPV devices. [ABSTRACT FROM AUTHOR]

Analyzing the defect states presence in semiconductors and understanding their impact on charge transport is essential to the solar cells' functionality. In recent years, there has been a focus on the concept of “defect tolerance” observed in perovskite solar cells. The energy‐resolved electrochemical impedance spectroscopy (ER‐EIS) is crucial for measuring the density distribution of defect states in the energy scale from valence to conductance band (or from HOMO to LUMO) and their spatial localization on a thin film. In this study, the aim is to better understand the concept of “defect‐tolerant materials” by comparing the surface and bulk densities of defect states obtained from ER‐EIS with the loss tangent at the frequency where the redox reactions determine the real part of the impedance. This comparison shows that the heterogeneity of the electronic structure across the thin film manifested as a higher surface density of states significantly impacts the failure of “defect tolerance” properties. The proposed procedure, being fast and efficient, has potential in the search for new materials and effective technological procedures for the conversion of solar energy into electricity. [ABSTRACT FROM AUTHOR]

Polyamide nylon 6 (PA6) films were fabricated using a solution casting method and the films were doped with SbCl5. The electrical conductivity increased with the dopant concentration due to the increase in formation of radical cations through the charge transfer from the isolated double bonds (–C=O–) in the polymer chains. The DC electrical conductivity reached a maximum of 0.01 S/cm for 0.5 ml SbCl5 doped films. Structural and optical characteristics of the pure and doped films were examined using Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), X-Ray Diffraction (XRD), and Ultraviolet-Visible (UV-Vis) absorption spectra. The doped films exhibited discernible shifts in the optical band gap energy. The direct band gap values of PA6 films were reduced from 4.5 eV to 1.7 eV when doped with 0.5 ml SbCl5. ATR-FTIR spectral studies, and optical studies indicated the formation of charge transfer complexes with the amide group of nylon 6, resulting in the electrical conduction. The XRD studies disclosed the reduction in the crystallinity of the doped films. The thermal stability was studied using differential scanning calorimetry (DSC) and thermogravimetric analysis-derivative thermogravimetric (TGA-DTG) studies. The melting and crystallization temperatures were recorded from the DSC thermograms. The peak melting temperature of PA6 reduced from 217 °C to 186 °C for 0.5 ml SbCl5 doped films. The peak of crystallization observed at 182 °C for pure films was absent, for the doped samples. The peak degradation temperatures for both pure and doped samples were above 400 °C, revealing the thermal stability of both materials. The thermally stable, semi-crystalline and semiconducting polymer films, we suggest, would be suitable for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Organic semiconductor (OSC) films fabricated by meniscus‐guided coating (MGC) methods are suitable for cost‐effective and flexible electronics. However, achieving crystalline thin films by MGC methods is still challenging because the nucleation and crystal growth processes are influenced by the intertwined interactions among solvent evaporation, stochastic nucleation, and the fluid flow instabilities. Herein, a novel flexible fountain pen with active ink supply is designed and used to print OSCs. This direct‐write method allows the flexible pen tip to contact the substrate, maintaining a robust meniscus by eliminating the gap found in conventional MGCs. An in situ optical microscopy observation system shows that the precursor film plays a critical role on the crystallization and the formation of coffee rings and dendrites. The computational fluid dynamics simulations demonstrate that the microstructure of the pen promotes extensional flows, facilitating mass transport and crystal alignment. Highly‐aligned ribbon‐shaped crystals of a small organic molecule (TIPS‐pentacene), as well as a semiconducting polymer (N2200) with highly‐ordered orientations, have been successfully printed by the flexible fountain pen. Organic field‐effect transistors based on the flexible pen printed OSCs exhibit high performances and strong anisotropic mobility. In addition, the flexible fountain pen is expandable for printing multiple lines or large‐area films. [ABSTRACT FROM AUTHOR]

The zinc selenide-sulfide (ZnSxSe1 – x) films were synthesized on glass substrates by a chemical bath deposition. Aqueous solutions of zinc chloride, sodium hydroxide, hydrazine hydrate, thiourea and powdered elemental selenium were used for the preparation of working solutions. The thiourea and selenium concentrations were varied to obtain different substitutional parameter values (x) of the films. The phase and elemental composition, optical transmittance spectra, and surface morphology of the deposited ZnSxSe1 – x films were investigated. According to the X-ray diffraction analysis, the film samples were single-phase and consisted of the ZnSxSe1 – x substitutionally solid solution in zincblende modification (ZnS structural type). The analysis of the elemental composition of the ZnSxSe1 – x films showed that the x value changed from 0.11 to 0.85, depending on the variations in thiourea and selenium concentrations. The film's surface was solid and contained particles of spherical shape. The optical transmittance of the ZnSxSe1 – x films increases across the investigated wavelength range from 340 to 900 nm. The transmittance curves have bends starting around the 340 nm region, shifting toward 650 nm for films with the highest selenium content, which is typical of ZnSxSe1 – x solid solutions. The determined optical band gap values of the ZnSxSe1 – x films ranged from 2.61 to 3.28 eV. [ABSTRACT FROM AUTHOR]

Semiconductor layers employed in fabricating advanced node devices are becoming thinner and their electrical properties are diverging from those established for highly crystalline standards. Since these properties also change as a function of depth within the film, accurate carrier profiling solutions are required. The Differential Hall Effect (DHE) technique has the unique capability of measuring mobility and carrier concentration (active carriers) through the depth of a semiconductor film. It comprises making successive sheet resistance and sheet Hall coefficient measurements as the thickness of the electrically active layer at a test region is reduced through successive material removal steps. Difference equations are then used to process the data and plot the desired depth profiles. The fundamentals of DHE were established in 1960s. Recently, the adaption of electrochemical processing for the material removal steps, and the integration of all other functionalities in a Differential Hall Effect Metrology (DHEM) tool, has made this technique more practical and accurate and improved its depth resolution to a sub-nm range. In this contribution, we review the development history of this important technique and present data from recent characterization work carried out on Si, Ge and SiGe layers. [ABSTRACT FROM AUTHOR]

Recently, plasma process-induced damage (PID) has garnered significant interest in the design of thin dielectric films implemented in semiconductor devices. Silicon nitride (SiN) films, a material of interest in strain engineering, are found to suffer from PID because they are exposed to various plasmas during device manufacturing processes. Only a limited amount of experimental evidence is available at present regarding plasma-induced mechanical property changes of SiN films. In this study, we investigated the mechanical property change in SiN and SiO2 films using a cyclic nanoindentation technique. We focused on the contact stiffness (S) as the principal mechanical property parameter. Firstly, a single loading/unloading test confirmed an increase in S after Ar and He plasma exposures. Subsequently, we examined the time-dependent features of damaged SiN and SiO2 films under cyclic loading/unloading. From the cyclic test, an increase in S was seen with the number of loading/unloading cycles (N) for both SiN and SiO2 films. A larger increase in S was observed for the damaged SiN, while no significant increase was seen for the damaged SiO2 films. The observed increase in S and its time dependence are attributed to the strain developed by the created defects (e.g. interstitial species) and the reconstruction and stabilization of plasma-damaged Si–N networks with created defects, respectively. The time-dependent S analysis under cyclic loading/unloading is useful for evaluating the effects of PID on the mechanical properties of thin films. [ABSTRACT FROM AUTHOR]

This study investigates the effect of electron beam irradiation on the structural and optical properties of Poly (3,4-ethylenedioxythiophene) polystyrene sulphonate (PEDOT: PSS) semiconductor films. PEDOT: PSS was deposited on thin films using spin coating technique at varying speeds of 1000, 2000, 3000, and 4000 rpm. Based on the pre-characterisation analysis, the thin film fabricated at 4000 rpm is identified as optimal. The fabricated PEDOT: PSS thin films were irradiated at doses of 10, 20, 30, 40 and 50 kGy at an energy of 1 MeV. The films were characterised using Atomic Force Microscopy (AFM), Ultraviolet–visible Spectroscopy (UV-Vis), X-ray diffractometer and energy dispersive X-ray spectroscopy (EDX). The optical properties of PEDOT:PSS thin film show that the transmittance was decreased after exposure to electron beam radiation, indicating a degradation with increasing total ionising dose (TID). The bandgap of irradiated PEDOT: PSS thin film shows a decreasing trend from 3.36 eV (unirradiated) to 3.30 eV (50 kGy) after the thin film was exposed to electron beam radiation at a maximum dose of 50 kGy. On the aspect of surface morphology, the AFM results show that the surface roughness of the PEDOT: PSS decreased with increasing TID, resulting in a smoother surface from 1.84 to 1.28 nm. Based on the XRD result obtained, the crystalline phase of the PEDOT: PSS thin film was maintained while the grain size improved from 264.87 nm (unirradiated) to 377.45 nm after exposure to electron beam radiation mainly at 30 and 40 kGy, indicating an optimised threshold exposure within the range. The findings provide valuable insight for developing organic semiconductors with enhanced structural, morphological and optical band gap properties after electron beam radiation exposure. [ABSTRACT FROM AUTHOR]

Multi‐phenyl and multi‐thiophene rod‐like molecules are typically used for weak epitaxial growth (WEG) of highly ordered organic semiconductor films enabling controllable microstructure properties and improved device performance. However, very few templating molecules have been reported, making it challenging to establish structure‐property relationships. As semiconductors are integrated into organic thin film transistors (OTFTs), the impact of templating layers on semiconductor microstructure and device performance must be established. Herein, four aromatic molecules with similar structure to para‐sexiphenyl (p‐6P) are synthesized and incorporated as the template layer in bis (pentafluoro phenoxy) silicon phthalocyanine (F10‐SiPc) OTFTs. The use of fluorinated p‐6P (p‐6PF) yields devices with the highest electron field‐effect mobility of 0.14 cm2 V−1 s−1 while a partially fluorinated p‐6P (p‐6PF4) results in improved threshold voltage. X‐ray diffraction (XRD) demonstrates varying F10‐SiPc crystallinity with choice of templating layer with the most crystalline films resulting from the use of p‐6PF. By grazing incidence wide angle X‐ray scattering (GIWAXS) and polarized Raman microscopy, all templating layers yield films with F10‐SiPc molecules predominantly aligned face‐on to the substrate. However, rod‐like p‐6P derivatives increased the face‐on orientation of F10‐SiPc. This study highlights the importance of template layer selection and deposition optimization in WEG‐based OTFTs. [ABSTRACT FROM AUTHOR]

Exciton–polariton condensates featuring collective coherence and large nonlinearities are promising for advancing coherent light sources and functional devices. Nevertheless, their reliance on planar cavities with large lateral device footprints and mode volumes hinders device integration. Plasmon–exciton–polaritons (PEPs), arising from the strong coupling between excitons and plasmons, provide an intriguing platform to explore emergent polariton condensation at the nanoscale due to their ultrasmall mode volumes in metal nanoparticles. However, the substantial radiative and Ohmic losses in metals hamper PEPs condensation, particularly in the short wavelength range (<600 nm). Here, a method is proposed to address metal losses by integrating organic semiconductor neat films onto plasmonic lattices. The use of organic semiconductors with large transition dipole moment and low non‐radiation loss enables efficient coupling between massive excitons and lattice plasmons, leading to high‐density PEPs. This ensures a macroscopic number of polaritons populating the low‐lying band edge at relatively low fluences to obtain bosonic stimulation, resulting in PEP condensation. By tailoring the band structures of plasmonic lattices, the condensation of PEPs are further manipulated into different energy states. These findings offer valuable insights for the design of PEP systems and all‐optical polaritonic devices. [ABSTRACT FROM AUTHOR]

Bio-artificial photosynthetic systems can reduce CO2 into multicarbon compounds by simulating natural photosynthesis. Here, inspired by organic photovoltaic structures, we demonstrate a bio-artificial photosynthetic system based on the hybridization of polymer semiconductor films and bacteria. The study suggests that the polymer-based semiconductor film can efficiently drive the non-photosynthetic bacteria to convert CO2 to acetate. By systematically characterizing the charge transport behavior of the bio-artificial photosynthetic system, the bulk-heterojunction structure and charge transport layers are proven to enhance the system performance markedly. The scalable floating artificial bio-leaf system can produce acetate to gram scale in a week. Notably, the semiconductor film is easy to recycle and maintains stable performance, showing good sustainable production capability of the system. A quasi-solid-state artificial bio-leaf is successfully prepared using agar to simulate the morphology and function of natural leaves. Last, the acetate production converted from CO2 was used to grow yeast for food production, thus achieving a complete simulation of natural photosynthesis. [ABSTRACT FROM AUTHOR]

Photodetectors are a key sensing component in enabling emerging technologies. For weak light detection, phototransistors with high responsivity are needed. Furthermore, the ability to fabricate phototransistors using solution processing techniques will enable new form factors, including flexible and large‐area devices. In this work, a novel approach for synthesizing a photosensitive organic/inorganic hybrid semiconducting thin film through solution processing is introduced. The approach involves hierarchical patterning of semiconducting carbon nanotubes (CNTs) with poly(3‐hexylthiophene‐2,5‐dyl) (P3HT) through solution‐phase heterogeneous crystallization. The fabricated hybrid phototransistors are qualified through electrical testing at varied illumination profiles within the visible light range. At a wavelength of 470 nm with an optical excitation power of 0.37 µW cm−2, the device exhibits photoresponsivity of 3.53 × 105 AW−1, surpassing other solution‐processed, non‐lead‐containing devices in the literature. The optical response extends from both photogating (low excitation power) and photon‐induced carrier generation (high excitation power). The detectivity of the device is ≈8.7 × 1010 Jones. The transient response includes a rise time of 100 ms and a fall time of 200 ms which is similar to the metrics of other low‐dimensional photodetectors. These findings highlight the prospects of the solution‐processed P3HT/semi‐CNT hybrid platform for advanced photodetection applications with flexible and large‐area form factors. [ABSTRACT FROM AUTHOR]

Despite recent dramatic improvements in the electronic characteristics of stretchable organic field-effect transistors (FETs), their low operational stability remains a bottleneck for their use in practical applications. Here, the operational stability, especially the bias-stress stability, of semiconducting polymer-based FETs under various tensile strains is investigated. Analyses on the structure of stretched semiconducting polymer films and spectroscopic quantification of trapped charges within them reveal the major cause of the strain-dependent bias-stress instability of the FETs. Devices with larger strains exhibit lower stability than those with smaller strains because of the increased water content, which is accompanied by the formation of cracks and nanoscale cavities in the semiconducting polymer film as results of the applied strain. The strain-dependence of bias-stress stability of stretchable OFETs can be eliminated by passivating the devices to avoid penetration of water molecules. This work provides new insights for the development of bias-stable stretchable OFETs. [ABSTRACT FROM AUTHOR]

Zinc Oxide (ZnO) nanorods have great potential in several applications including gas sensors, light-emitting diodes, and solar cells because of their unique properties. Here, three low cost and ecofriendly techniques were used to produce ZnO nanorods on FTO substrates: hydrothermal, chemical bath deposition (CBD), and electrochemical deposition (ECD). This study explores the impact of such methods on the optical, structural, electrical, morphological, and photoelectrochemical properties of nanorods using various measurements. XRD analysis confirmed the hexagonal wurtzite structure of ZnO nanorods in all three methods, with hydrothermal showing a preferred orientation (002) and CBD and ECD samples showing multiple growth directions, with average particle sizes of 31 nm, 34 nm, and 33 nm, respectively. Raman spectra revealed hexagonal Wurtzite structure of ZnO, with hydrothermal method exhibiting higher E2 (high) peak at 438 cm−1 than CBD and ECD methods. SEM results revealed hexagonal ZnO nanorods became more regular and thicker for the hydrothermal method, while CBD and ECD led to less uniform with voids. UV-vis spectra showed absorption lines between 390 nm and 360 nm. Optical bandgap energies were calculated as 3.32 eV, 3.22 eV, and 3.23 eV for hydrothermal, CBD, and ECD samples, respectively. PL spectra revealed UV emission band with a small intensity peak around 389 nm and visible emission peaks at 580 nm. Temperature dependent PL measurements for ZnO nanorods indicated that the intensities ratio between bound exciton and free exciton decreases with temperature increases for the three methods. Photocurrent measurements revealed ZnO nanorod films as n-type semiconductors, with photocurrent values of 2.25 µA, 0.28 µA, and 0.3 µA for hydrothermal, CBD, and ECD samples, and photosensitivity values of 8.01, 2.79, and 3.56 respectively. Our results suggest that the hydrothermal method is the most effective approach for fabricating high-quality ZnO nanorods for optoelectronic applications. [ABSTRACT FROM AUTHOR]

This work proposes an original method that reveals the transformation dynamics of nanosized Bi films into semiconductor films of bismuth oxide (Bi2O3) and the factors affecting the low‐energy cold plasma on the electro‐optical properties of Bi2O3. In the plasma microreactor with a photosensitive GaAs:Cr electrode, the transformed Bi films 400–1100 nm thick are analyzed by X‐ray diffraction to determine the crystal structure of Bi2O3 and by an electron probe microanalyzer to explore the evolution of the composition. The morphological properties of the Bi films exposed to electron–ion flow are examined by processing the scanning electron microscope images. It is found that as a result of the combined effect of photoactive illumination, charged particles, and active plasma components: 1) an absorption spectrum of a new substance is formed in the range λ = 330–1100 nm; 2) the optical width of the bandgap of the resulting substance is Eg ≈ 3 eV, which satisfactorily coincides with the width of the bandgap of Bi2O3; and 3) to overcome the potential barrier and formation of semiconducting Bi2O3 film energy is required, which is provided by the combined kinetic energy of electrons and negatively charged oxygen ions bombarding on the Bi film. [ABSTRACT FROM AUTHOR]

Semiconducting photoresists hold great promise for scale‐up manufacturing of organic field‐effect transistors (OFETs) for integrated organic electronics. While photolithographic p‐type OFETs have achieved a considerable balance among patterning precision, electrical properties and process stability, it remains challenging for n‐type OFETs due to the inherent limited mobility and ambient instability. Herein, a n‐type semiconducting photoresist (SPr) is developed that is compatible with photolithography procedures. By utilizing the solvent‐driven force, a self‐encapsulated blend film with gradient semiconductor phase is prepared, where the underneath transistor active layer is protected by the upper cross‐linked network, avoiding solvent erosion and air doping. As such, a mobility up to 1.1 cm2 V−1 s−1 that is comparable with amorphous Si is achieved, with remained mobility by ≈90% after long‐term exposure to developer and stripper or atmospheric conditions. The sub‐micrometer patterning accuracy of SPr enables the fabrication of organic transistor arrays with a density of 9 × 105 units cm−1, which is comparable to other state‐of‐the‐art devices fabricated by the printing or photolithography, demonstrating immense potential in integrated organic electronics. [ABSTRACT FROM AUTHOR]

Thin films of BiOCl, BiOBr, and BiOI (BiOX) were deposited by thermal evaporation for their potential application in the decontamination of water and air through their photocatalytic activity, which was compared among the three. The BiOX thin films were subjected to characterization through X-ray diffraction, high-resolution transmission electron microscopy, and scanning electron microscopy. Additionally, the optical properties were determined from the diffuse reflectance spectrum obtained with a spectrophotometer. To assess the efficacy of the semiconductor films in water decontamination, the evolution of rhodamine B discoloration and its mineralization was monitored by measuring total organic carbon. The decontaminating activity in the air was evaluated in a gas reactor, measuring the conversion of NOx-type gases. The results demonstrated that the thin films of the three oxides exhibited decontaminating photocatalytic activity in both water and air. However, notable distinctions were observed in the photocatalytic activities of the three bismuth oxyhalides in water, while in air, they exhibited similarities. In aqueous environments, the mineralization percentages exhibited notable variation after 96 h, with the BiOBr film displaying a value of 9.2%/mg and the BiOCl film a value of 3.9%/mg. In contrast, the NO conversion rate in the air was approximately 0.6%/mg for the three oxyhalide films. [ABSTRACT FROM AUTHOR]

The scientific direction of the synthesis of CdS and CdSe thin films by the method of chemical surface deposition (CSD) using the aqueous solutions of cadmium-containing salts: chloride, nitrate, sulphate, acetate and iodide has been developed. A mathematical model of the CSD process of CdS and CdSe thin films was developed to improve the efficiency of experiments and reduce costs. The model makes it possible to determine the concentration of reagents, the duration, and the CSD temperature, which are necessary to obtain films of a specified thickness. The optimization of chemical deposition parameters of filmtype semiconductor materials has been carried out. Based on the mathematical model, the optimal synthesis conditions were the following: the concentration of cadmium-source salt - 0.01 mol/L, chalcogenizer - 1.0 mol/L or 0.1 mol/L in the case of thiourea or sodium selenosulphate, respectively; the temperature: 70 °C and the duration of 3 min. The mathematical dependence of the experimental studies results of the metal ions content in thin-film solar cells for the effective direct conversion of solar radiation into electrical energy was proposed taking errors into account. [ABSTRACT FROM AUTHOR]

Theoretical description of electronically excited states of molecular aggregates at an ab initio level is computationally demanding. To reduce the computational cost, we propose a model Hamiltonian approach that approximates the electronically excited state wavefunction of the molecular aggregate. We benchmark our approach on a thiophene hexamer, as well as calculate the absorption spectra of several crystalline non-fullerene acceptors, including Y6 and ITIC, which are known for their high power conversion efficiency in organic solar cells. The method qualitatively predicts the experimentally measured spectral shape, which can be further linked to the molecular arrangement in the unit cell. [ABSTRACT FROM AUTHOR]

Unipolar p‐ and n‐type organic field‐effect transistors (OFETs) are essential for constructing organic circuits and complementary designs crucial for high‐performance electronics. Traditionally, fabricating these transistors requires separate p‐type and n‐type organic semiconductors (OSCs), which complicates the process due to intricate patterning, protection of the first OSC layer, and considerable material wastage. In this work, an innovative approach is introduced, inspired by silicon transistor fabrication to obtain unipolar OFETs, employing a single ambipolar OSC in conjunction with doped organic semiconductor films (DOSCFs) as electrodes. This results demonstrate that OFETs with DOSCF electrodes suppress ambipolarity dramatically and achieve on/off ratios that are two to three orders of magnitude higher than those with metal electrodes, along with excellent stability. The unipolar characteristics of the devices are attributed to the unique work function properties and the intrinsic charge carrier behavior of the DOSCF electrodes. Significantly, inverter circuits utilizing these unipolar transistors outperformed traditional ambipolar transistors with metal electrodes, achieving a fivefold increase in voltage gain. This novel strategy promises to enhance the practicality and economic viability of organic electronics, paving the way for more sustainable and high‐performance circuit designs. [ABSTRACT FROM AUTHOR]

Growing crack-free, epitaxial ultrawide-bandgap semiconductor films on cost-effective, large-area substrates, such as AlN on Si, poses a significant challenge due to substantial lattice and thermal expansion mismatches. We introduce an approach to mitigate tensile strain or reverse strain signs between the substrate and the AlN layer, thereby suppressing crack formation during the heteroepitaxial growth of thick III-N films. This approach introduces ductile metallic interlayers, specifically Au, to change the strain state of AlN from in-plane tensile to compressive, without initiating cracks. Furthermore, the Au interlayer is grown epitaxially as a single crystal, which prevents the transfer of tensile strain into the AlN film, as confirmed by x-ray diffraction and transmission electron microscopy. We demonstrate crack-free AlN films exceeding 1 μm in thickness. These findings hold significant promise for advancing the field of ultrawide-bandgap semiconductor materials, with potential applications in electronic, optoelectronic, sensing, and energy device applications. [ABSTRACT FROM AUTHOR]

Band structure of a semiconducting film critically determines the charge separation and transport efficiency. In antimony selenosulfide (Sb2(S,Se)3) solar cells, the hydrothermal method has achieved control of band gap width of Sb2(S,Se)3 thin film through tuning the atomic ratio of S/Se, resulting in an efficiency breakthrough towards 10 %. However, the obtained band structure exhibits an unfavorable gradient distribution in terms of carrier transport, which seriously impedes the device efficiency improvement. To solve this problem, here we develop a strategy by intentionally regulating hydrothermal temperature to control the chemical reaction kinetics between S and Se sources with Sb source. This approach enables the control over vertical distribution of S/Se atomic ratio in Sb2(S,Se)3 films, forming a favorable band structure which is conducive to carrier transport. Meanwhile, the adjusted element distribution not only ensures the uniformity of grain structure, but also increases the Se content of the films and suppress sulfur vacancy defects. Ultimately, the device delivers a high efficiency of 10.55 %, which is among the highest reported efficiency of Sb2(S,Se)3 solar cells. This study provides an effective strategy towards manipulating the element distribution in mixed‐anion compound films prepared by solution‐based method to optimize their optical and electrical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] The effect of UV irradiation on sol–gel prepared ZnO films subjected to mild thermal annealing was investigated, with special attention to their structural and surface properties. Sol–gel processes, including a high-temperature annealing stage, have been adapted to the requirements of flexible electronics for in situ synthesis of semiconductor ZnO films on polymer substrates at lower temperatures due to UV irradiation. Application of UV radiation with emission peaks at 185 and 254 nm to films annealed at 180 °C made it possible to obtain ZnO films with Zn/O ratios of ca. 1, which cannot be achieved by heat treatment alone. [ABSTRACT FROM AUTHOR]

Highly stretchable aerogel films are attractive for advanced next‐generation stretchable electronics. However, it is a great challenge to achieve high stretchability for aerogel films. Here, several types of unprecedented ultra‐stretchable semiconducting polymer‐based aerogel films with crimpled porous structures are developed via crosslinking and template methods combined with uniaxial and biaxial pre‐stretching strategies. The semiconducting aerogel films obtained by uniaxial pre‐stretching exhibit ultrahigh stretchability up to 100–200%, while those obtained by biaxial pre‐stretching show high biaxial stretchability up to 50%. The resulting aerogel films show strain‐insensitive electrical and joule heating properties. A prototype of the aerogel film‐based stretchable organic electrochemical transistor (OECT) is developed for the first time. Benefiting from their unique porous structures, the aerogel film‐based OECTs exhibit enhanced on/off ratio and transconductance compared with corresponding dense film‐based OECTs, high stretchability up to 100%, and high stretching stability with 10 000 stretching cycles under 30% strain. It is demonstrated that the aerogel film‐based OECTs can be applied as high‐performance stretchable artificial synapses and biosensors. This work gives a versatile strategy toward highly stretchable aerogel films promising for flexible electronics. [ABSTRACT FROM AUTHOR]

The market demand for optoelectronic devices is increasing, leading to a need for low‐cost, high‐performance image sensors that can operate effectively in challenging environments such as darkness and fog. The emerging 2D transition metal dichalcogenides (TMDs) have garnered significant interest due to their exceptional optoelectronic properties and compatibility with silicon (Si) complementary metal oxide semiconductor (CMOS) technology. However, the large‐scale synthesis of TMD films and uniform preparation of photodiode arrays remain challenging. This paper reports a synthesis method for heteroepitaxial growth of 2H‐ molybdeum diyelluride (MoTe2) semiconducting films on 3D wafer‐level Si substrates. Using this method, arrays of 2H‐MoTe2/Si heterojunction photodiodes are prepared that demonstrate excellent uniformity and 100% device yield. The photodiodes exhibit satisfactory optoelectronic properties, including a small dark current maintained within a range of 1–3 nA and a maximum responsivity of 521.1 mAW−1 under near‐infrared light at 800 nm, with rise and fall times of less than 4 ms. To demonstrate the image‐sensing capabilities of the photodiode array under visible and near‐infrared (NIR) light illumination, a complete imaging system is designed.The MoTe2/Si photodiode arrays examined in this study offer a practical solution for integrating Si‐based readout circuits and photodetector arrays on a single chip. [ABSTRACT FROM AUTHOR]

High-performance alloy thin films and large-sized thin film wafers for infrared applications are the focus of international researchers. In this study, doped Ge1−xSnx and Ge1−yBiy semiconductor alloy films were grown on a 5-in. silicon (Si) wafer using high-quality Ge films as buffer layers. An efficient technique is presented to reduce the dark current density of near-infrared photoelectric devices. By using boron for p-type doping in Ge1−xSnx films and bismuth (Bi) for n-type doping in Ge1−yBiy films, an all-thin film planar nano-p-i-n optoelectronic device with the structure n-Ge1−yBiy/i-GeSn/p-Ge1−xSnx/Ge buffer/Si substrate has been successfully fabricated. The photoelectric performance of the device was tested, and it was found that the insertion of p-Ge1−xSnx/Ge films reduced the dark current density by 1–2 orders of magnitude. The maximum photoresponsivity reached up to 0.8 A/W, and the infrared photocurrent density ranged from 904 to 935 μA/cm2 under a +1 V bias voltage. Furthermore, the device is capable of modulating a terahertz wave using a voltage signal with a modulation bandwidth of 1.2 THz and a modulation depth of ∼83%, while the modulation rate is 0.5 MHz. This not only provides a clear demonstration of how doped alloy films and the development of nano-p-i-n heterojunctions will improve photoelectric devices' performance in the near-infrared and terahertz bands, but it also raises the possibility of optoelectronic interconnection applications being achieved through a single device. [ABSTRACT FROM AUTHOR]

This work presents the synthesis of para-quinone methides (p-QMs), which were deposited as films using the high vacuum sublimation technique after being chemically characterized. The p-QMs films were characterized morphologically and structurally using scanning electron microscopy, atomic force microscopy, and X-ray diffraction. In addition, their optical behavior was studied by means of ultraviolet–visible spectroscopy, and the optical gaps obtained were in the range of 2.21–2.71 eV for indirect transitions, indicating the semiconductor behavior of the p-QMs. The above was verified through the manufacture and evaluation of the electrical behavior of rigid semiconductor devices, in which fluorine-doped tin oxide-coated glass slides (FTO) were used as an anode and substrate. Finally, as an original, ecological, and low-cost application, the FTO was replaced by substrates and anodes made from recycled Tetra Pak®, generating flexible semiconductor devices. Although the electrical current transported depends on the type of p-QMs, the substituent in its structure, and the morphology, the kinds of substrate and anode also influence the type of electrical behavior of the device. This current–voltage study demonstrates that p-QM2 with 4-Cl-Ph as a radical, p-QM3 with 4-Et2N-Ph as a radical, and p-QM6 with 5-(1,3-benzodioxol) as a radical can be used in optoelectronics as semiconductor films. [ABSTRACT FROM AUTHOR]

Our study of magnetization switching in crystalline (Ga,Mn)(As,P) ferromagnetic semiconductor (FMS) film by spin-orbit torque (SOT) has revealed an unexpected increase in critical switching current as the in-plane magnetic bias field is increased beyond a certain point. This intriguing behavior is ascribed to depolarization of spin-polarized current induced by the application of bias field perpendicular to the direction of current carrier spins. This is particularly interesting, because the bias field is itself a necessary requirement for achieving the deterministic SOT magnetization switching. To gain understanding of this unexpected behavior, we incorporated the process of spin depolarization into micromagnetic simulation study of SOT magnetization switching in the (Ga,Mn)(As,P) system. Through simulations that include effects of spin depolarization, we were able to replicate the observed increase in the required critical switching current as the in-plane bias field is increased. Furthermore, our study demonstrates that the dependence of critical switching current on bias field can be quantitatively described by adjusting magnetic anisotropy parameters of the film. This study not only enhances our understanding of SOT phenomena but also offers valuable insights for tailoring and optimizing FMS materials for spintronic applications. [ABSTRACT FROM AUTHOR]

The results of direct femtosecond laser structuring of GaAs wafer coated with continuous semitransparent gold (Au) film are presented. The obtained structures demonstrate a combination of different features, namely laser-induced periodic surface structures (LIPSS) on semiconductor and metal film, nanoparticles, Au islands, and fragments of exfoliated Au film. The properties of Au-GaAs samples are studied with scanning electron microscopy (SEM), Raman scattering, and photoluminescence (PL) spectroscopy. The behaviour of phonon modes and enhancement of band-edge PL of AuGaAs composite sample are discussed. The Raman spectra of Au-GaAs sample processed at different levels of irradiation pulse energy reveal forbidden TO and allowed LO phonon modes for selected geometry of experiment, as well as the manifestation of GaAs surface oxidation and amorphization. A 12-fold increase of PL intensity for Au-GaAs sample with LIPSS compared to initial GaAs surface is observed. The detected PL enhancement is caused by an increase of absorption in GaAs due to the light field enhancement near the Au nanoislands and a decrease of nonradiative surface recombination. The blue shift of PL band is caused by the quantum size effect in GaAs nano-sized features at laser processed surface. The combination of GaAs substrate with surface micro- and nanostructures with Au nanoparticles can be useful for photovoltaic and sensorics applications. [ABSTRACT FROM AUTHOR]

In this work, we developed an optimized ultrasonic spray pyrolysis device for obtaining metal oxide films. The key benefit of this facility lies in its cost-effectiveness and its ability to consistently coat extensive surfaces without sacrificing the integrity of the semiconductive films, thus streamlining the manufacturing process of semiconductor films. The resulting films exhibit the following attributes: the thickness of the deposited layer is approximately 400 nm, while the diameters of ZnO1-xSx nanocrystals range from 50 to 200 nm, oriented perpendicular to the crystallographic orientation (111). In the production of nanorods, the average height is estimated to be approximately 30-50 nm, with a density of 2.9×1011 cm-2 being indicated. [ABSTRACT FROM AUTHOR]

This work aims to examine the optoelectrical, optical, and structural properties of novel polycrystalline SrZnO2 layers fabricated by a cost-effective nebulizer spray pyrolysis procedure at varying thicknesses (237, 395, 468, and 529 nm). The X-ray diffractograms have been used in this work to study the structure of the SrZnO2 films. The SrZnO2 films possessed an orthorhombic structure. The computational analysis involved determining the structural indices, including grain size, dislocation density, and lattice strain, of the SrZnO2 films. Energy dispersive X-ray analysis has been used to verify the stoichiometry of these SrZnO2 films. The surface morphology of the SrZnO2 layers has been studied using the field-emission scanning electron microscope. The optical characteristics of the SrZnO2 films have been investigated by the spectrophotometric measurements in the range 400–2500 nm. The optical results of the SrZnO2 films depicted that the enhancement of the refractive index, Urbach's energy, and absorption coefficient of these films by boosting the thickness. Meanwhile, the improvement in the crystallization process led to a small decrease in the optical band gap energy values of the SrZnO2 layers from 2.91 to 2.68 eV as the film thickness grew. Furthermore, the analysis of the optoelectrical characteristics of the SrZnO2 films showed that the boost in film thickness enhanced the values of plasma frequency, optical resistivity, optical carrier concentration, optical mobility, and optical conductivity. The nonlinear optical properties of the SrZnO2 layers have been boosted by the thickness growth. On the other hand, the hot probe equipment revealed that both the SrZnO2 layers exhibited n-type semiconducting characteristics. The acquired results validate the wide bandgap semiconductor nature of these films. Consequently, it is advisable to use them as a window layer in various solar cell applications. The electrical results illustrated that the estimated activation energy of the SrZnO2 films decreases as the thickness rises. [ABSTRACT FROM AUTHOR]

Here, the effect of thermal annealing (TA) on the stability of solution‐sheared thin films of the semiconducting polymer poly[2,5‐bis(2‐octyldodecyl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione‐3,6‐diyl)‐alt‐(2,2′;5′,2′';5′',2′"‐quaterthiophen‐5,5′"‐diyl)] (PDPP4T) against the original coating solvent is studied, and it is shown that TA significantly improves the solvent resistance of semiconducting polymer films. Specifically, after the thin films are annealed at or above a critical temperature, the thin film thickness is largely retained when exposed to the original solvent, while for lower annealing temperatures material loss occurs, i.e., the thin film thickness is reduced due to rapid dissolution. The results of various techniques including grazing‐incidence wide‐angle x‐ray scattering (GIWAXS), atomic force microscopy (AFM), and ultraviolet‐visible‐near infrared (UV–vis‐NIR) absorption spectroscopy suggest physical changes as the cause for the increased solvent resistance. Such annealed films also show stable electrical characteristics in bottom‐gate, top‐contact (BGTC) organic field‐effect transistors (OFETs) even after solvent exposure. In initial tests, a multitude of technologically relevant polymers show such behavior, underlining the potential impact of such temperature treatments for the fabrication of multi‐layer polymer devices. [ABSTRACT FROM AUTHOR]

Directional ionic migration in ultra-thin metal-oxide semiconductors under applied electric fields is a key mechanism for developing various electronic nanodevices. However, understanding charge transfer dynamics is challenging due to rapid ionic migration and uncontrolled charge transfer, which can reduce the functionality of microelectronic devices. This research investigates the supercapacitive-coupled memristive characteristics of ultra-thin heterostructured metal-oxide semiconductor films at TiO2-In2O3/Au Schottky junctions. Using atomic layer deposition (ALD), we nano-engineered In2O3/Au-based metal/semiconductor heterointerfaces. TEM studies followed by XPS elemental analysis revealed the chemical and structural characteristics of the heterointerfaces. Subsequent AFM studies of the hybrid heterointerfaces demonstrated supercapacitor-like behavior in nanometer-thick TiO2-In2O3/Au junctions, resembling ultra-thin supercapacitors, pseudocapacitors, and nanobatteries. The highest specific capacitance of 2.6 × 104 F.g−1 was measured in the TiO2-In2O3/Au junctions with an amorphous In2O3 electron gate. Additionally, we examined the impact of crystallization, finding that thermal annealing led to the formation of crystalline In2O3 films with higher oxygen vacancy content at TiO2-In2O3 heterointerfaces. This crystallization process resulted in the evolution of non-zero I-V hysteresis loops into zero I-V hysteresis loops with supercapacitive-coupled memristive characteristics. This research provides a platform for understanding and designing adjustable ultra-thin Schottky junctions with versatile electronic properties. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal Coatings titled "Recent Advances in the Development of Thin Films." The issue includes thirteen contributions, including two reviews and eleven research articles, covering various aspects of thin films. The articles explore topics such as deposition and characterization techniques, synthesis and characterization of thin films with specific properties, assessment of mechanical and electrical properties, and applications of thin films in sensing and solar cell technologies. The issue highlights the ongoing innovation in the field of thin films and their potential applications in various industries. [Extracted from the article]