Solution Deposition Research Articles

Simple chemical solution deposition of Al2O3 dielectric layers for low-cost fabrication of transparent electronic devices

Simple chemical solution deposition of Al2O3 dielectric layers for low-cost fabrication of transparent electronic devices

Additive-Assisted Hydrothermal Growth Enabling Defect Passivation and Void Remedy in Antimony Selenosulfide Solar Cells.

Antimony selenosulfide (Sb2(S,Se)3) has recently emerged as a promising light-absorbing material, attributed to its tunable photovoltaic properties, low toxicity, and robust environmental stability. However, despite these advantages, the current record efficiency for Sb2(S,Se)3 solar cells significantly lags behind their Shockley-Queisser limit, especially when compared to other well-established chalcogenide-based thin-film solar cells, such as CdTe and Cu(In,Ga)Se2. This underperformance primarily arises from the formation of unfavorable defects, predominately located at deep energy levels, which act as recombination centers, thereby limiting the potential for performance enhancement in Sb2(S,Se)3 solar cells. Specifically, deep-level defects, such as sulfur vacancy (VS), have a lower formation energy, leading to severe non-radiative recombination and compromising device performance. To address this challenge, thioacetamide (TA), a sulfur-containing additive is introduced, into the precursor solution for the hydrothermal deposition of Sb2(S,Se)3. This results indicate that the incorporation of TA helps in passivating deep-level defects such as sulfur vacancies and in suppressing the formation of large voids within the Sb2(S,Se)3 absorber. Consequently, Sb2(S,Se)3 solar cells, with reduced carrier recombination and improved film quality, achieved a power conversion efficiency of 9.04%, with notable improvements in open-circuit voltage and fill factor. This work provides deeper insights into the passivation of deep-level donor-like VS defects through the incorporation of a sulfur-containing additive, highlighting pathways to enhance the photovoltaic performance of Sb2(S,Se)3 solar cells.

Integration Of Solution‐Processed BaTiO3 Thin Films with High Pockels Coefficient on Photonic Platforms

AbstractThe heterogeneous integration of ferroelectric BaTiO3 thin films on silicon (Si) and silicon nitride (SiN)‐based platforms for photonic integrated circuits (PICs) plays a crucial role in the development of future nanophotonic thin film modulators. Since the electro‐optic (EO) properties of ferroelectric thin films strongly depend on their crystal phase and texture, the integration of BaTiO3 thin films on these platforms is far from trivial. So far, a conventional integration route using a SrTiO3 template film in combination with high vacuum deposition methods has been developed, but it has a low throughput, is expensive and requires monocrystalline substrates. To close this gap, a cost‐efficient, high‐throughput and scalable method for integrating highly textured BaTiO3 films is needed. Therefore, an alternative method for the integration of highly textured BaTiO3 films using a La2O2CO3 template film in combination with a chemical solution deposition (CSD) process is presented. In this work, the structural and EO properties of the solution‐processed BaTiO3 film are characterized and its integration into an optical ring resonator is evaluated. The BaTiO3 film exhibits a fiber texture, has a large Pockels coefficient (reff) of 139 pm V−1, and integration into a ring resonator‐based modulator shows a VπL of 1.881 V cm and a bandwidth of > 40 GHz. This enables low‐cost, high‐throughput, and flexible integration of BaTiO3 films on PIC platforms and the potential large‐scale fabrication of nanophotonic BaTiO3 thin‐film modulators.

Control of Ferroelectricity in Solution‐Processed Hafnia Films Through Annealing Atmosphere

AbstractChemical Solution Deposition enables low‐cost fabrication of ferroelectric HfO2 films suitable for piezoelectric applications. Control of processing parameters is of utmost importance to obtain high‐quality functional films. However, the impact of the annealing atmosphere on ferroelectric properties of solution‐processed HfO2 films is not clear. In this work, the influence of annealing atmosphere and growth methods on orientation, density and electrical properties of La:HfO2 films is studied. The 45 nm‐thick films are grown by two routes, conventional (crystallization of the final 45 nm‐thick film) and layer‐by‐layer (intermediate crystallizations of 5 nm‐thick films). Annealing is performed in N2:O2 and Ar atmosphere. Films grown by layer‐by‐layer method in an oxygen‐rich atmosphere tend to have higher density (87% of theoretical density) and remanent polarization (15 µC cm–2) than the conventional films (density and remanent polarization of 80% and 7.5 µC cm‐2). Secondary ion mass spectrometry reveals higher amounts of carbon presence in the conventional films annealed in Ar. For layer‐by‐layer films, the ability to control the preferential out‐of‐plane orientation from (111) to (002) simply by changing the annealing atmosphere, is demonstrated. The results can guide the path toward high‐quality thicker films for piezoelectric applications.

Combined Effect of Underlayer and Deposition Solution to Optimize the Alignment of Hematite Photoanodes.

This study investigates the optimization of hematite (α-Fe2O3) photoanodes for enhanced photoelectrochemical (PEC) performance and reproducibility, which are crucial for photocatalytic applications. Despite hematite's potential, hindered by inherent limitations, significant improvements were realized by introducing a titanium dioxide (TiO2) underlayer and ethanol-modified deposition. The influence of the deposition methods was understood by potential-dependent photoelectrochemical impedance spectroscopy analysis. The introduction of the TiO2 underlayer effectively increased the density of states, preferable for the electron transport in the bulk hematite, and the ethanol deposition on a TiO2 underlayer led to a stable surface state formation (S1 state) for the photoexcited hole transfer. This analysis illuminated the intricate interplay between electron transport in the bulk and photogenerated hole transfer at the solution interface, thereby facilitating smoother charge transfer. These findings underscore the viability of surface engineering and meticulous process optimization in addressing critical challenges in photocatalyst development.

PZT based dual energy harvester using chemical solution deposition technique

The present finding reports the state-of-art thin film based dual energy harvester which can harvest both mechanical as well as magnetic energies. Dual energy harvester is realised with the help of Lead Zirconium Titanate (PZT) thin film and nickel (Ni) foil. Ferroelectric PZT has been grown with the help of chemical solution deposition technique under optimised conditions on Nickel cantilevers. The effect of damping mass on the resonating frequency of the PZT-60/Ni dual cantilever has been studied. The maximum power and voltage generated by dual energy harvester at the matching load impedance of 100 kΩ under resonance condition were about 117 × 102 mW/m3 and 52 mV respectively corresponding to an applied acceleration of 1.0 g. A change of about 0.5 mV/Oe voltage was achieved for PZT-60/Ni cantilever in the presence of magnetic field. The dual energy harvester prepared with the help of chemical solution technique is found to have profound response and hence enables the realization of self powered electronic devices by scavenging an ambient magnetic and mechanical energies for various wireless electronic applications ranging from medical implant to health monitoring areas.

Scalable and environmentally friendly production of perovskite manganite thin films for neuromorphic applications

A method of producing high-quality thin films of perovskite manganites utilizing citrate-based aqueous chemical solution deposition is presented. The method is applied to the production of thin films of gadolinium calcium manganite, Gd1−xCaxMnO3 (GCMO). The film quality is verified by x-ray diffraction analysis, electron microscopy, and magnetic measurements. Finally, planar memristors are fabricated using GCMO films, demonstrating the material’s ability to exhibit resistive switching. This underscores its potential for future memristor technologies.

Enhancement of ferroelectricity in chemical-solution-deposited ZrO2 thin films through fine phase transition control

Recent studies have highlighted the ferroelectric potential of ZrO2 thin films, which offer advantages over HfO2-based ferroelectric materials, such as lower thermal budget and greater natural abundance. In this research, pure ZrO2 ferroelectric thin films were fabricated on Si substrates using chemical solution deposition with all-inorganic precursors. We explored the impacts of film thickness and HfO2 seed layers on phase transition and ferroelectric properties. Notably, an 11 nm thick ZrO2 film exhibited ferroelectric behavior with a remanent polarization of 12.6 μC/cm2. Due to the combined effects of tensile stress and surface energy, the increase in thickness to 30 nm led to a phase transition from the orthorhombic phase to the monoclinic phase and a resultant decrease in remanent polarization. Additionally, the introduction of a HfO2 seed layer facilitated the crystallization of the ferroelectric o-phase, enhancing the remanent polarization to 16.5 μC/cm2 in our ∼8 nm thick ZrO2 thin film with a ∼2 nm thick HfO2 seed layer. These findings provide valuable insights into optimizing ferroelectric properties in ZrO2 thin films through phase transition control.

Investigation of the influence of nano-CrN concentration on the performance of Ni-W coatings in X80 pipeline steel

A novel nano Ni-W-CrN composite coating was developed for X80 pipeline steel to enhance its structural properties and corrosion resistance. The study explored the effects of varying CrN nanoparticle concentrations (0, 5, 10, 15, 20 g/L) in the deposition solution using techniques such as SEM, EDS, and XRD for analysis and an electrochemical workstation for corrosion testing. The optimal CrN concentration was identified at 10 g/L, resulting in a coating with peak hardness (811HV), low friction coefficient (0.16), minimal wear rate (1.18×10−4 mm3·(N·m)−1), and improved corrosion resistance. This coating significantly outperforms Ni-W alloy coatings in hardness, wear resistance, and elastic recovery, offering a promising approach for enhancing the performance of X80 pipeline steel surfaces.

Influence of the DEA Concentration on Structural and Optical Properties of Nanodot PbS Thin Films Growth by Chemical Solution Deposition: Unveiling Dual Optical Absorption Edges

The present paper presents a straightforward method for producing thin film layers of sulfide quantum dots (PbS-QDs) on a glass substrate using chemical solution deposition (CSD) assisted by dipcoating technique. The deposited PbS-QDs films were subjected to a comprehensive analysis using atomic force microscopy (AFM), energy dispersive X-ray (EDX) scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–vis–IR absorption, and photoluminescence spectroscopic (PL) techniques to investigate the effects of varying concentrations of diethanol amine (DEA) on their morphology, crystal structure, elemental composition, light absorption, and emission characteristics. The spherical shape of the PbS-QDs was confirmed by AFM and SEM images with average sizes around 100 and 50 nm, respectively. The energy dispersive X-ray (EDX) analysis provides evidence the existence of Pb and S elements within the PbS matrix. X-ray diffraction (XRD) results validate that the deposited films exhibit high crystallinity, with a preferential orientation along the (111) plane and a face-centered cubic lattice structure of PbS. The crystallite size of PbS is measured to be 46.6 nm. Based on the optical absorption measurements, we have determined the size range of PbS nanocrystals to be between 4.3 and 11.5 nm. The optical studies reveal the presence of two optical absorption edges within the visible and infrared spectrum, two direct band gap energy, two cut-off wavelengths, two confinement energy, two Urbach energy tail, and dual emission peaks of PbS-QDs at room temperature. The analysis reveals the presence of two distinct band gap energies, one in the visible range (1.3–2.28 eV) and the other in the infrared range (0.65–0.88 eV), which can be attributed to the formation of two distinct sizes of quantum dots situated in two different layers. The first layer, deposited directly on the glass substrate, comprises quantum dots with an average size of approximately 5.2 nm, while the second layer contains quantum dots with an average size of about 9.5 nm. This ability to tune the band gap of PbS in the visible range up to the IR band (0.65–2.28 eV) is a critical feature that holds the potential for the development of innovative optoelectronic devices.

Application of carbazole derivatives as a multifunctional material for organic light-emitting devices

The object of research is newly synthesized carbazole-derived compounds and organic light-emitting structures based on them. The problem lies in the complex solution of scientific and technical problems of improving the characteristics and stability of organic light-emitting diodes (OLEDs), namely improving the brightness and energy-efficient parameters. Organic light-emitting structures of blue, blue, and green radiation with color coordinates were formed by the thermovacuum sputtering method and the solution deposition method. The turn-on voltage of the white OLED is 6 V, the maximum brightness of the light-emitting structures was 10,000 cd/m2. The devices demonstrated a sufficiently high external quantum efficiency of 5 % to 7 %. This paper reports the multifunctional application of a simple donor-acceptor organic compound, as active and host material in the emission layer of organic light emitting devices. Em1 has been used as active components in OLEDs, where Em1 is the guest emitter (Device A), the acceptor part of the excited emitter (Device B) and the host matrix of the CdSeS/ZnS alloy quantum dot. At least four different OLEDs have been designed and characterized where Em1 plays the role of the guest emitter (Device C). The external quantum efficiencies of devices A–C are characterized by values common to pure fluorescent OLEDs (up to 5 % of the theoretical limit), but these devices sustain low-efficiency roll-off of electroluminescence over a wide range of current densities. Organic light-emitting diodes based on carbazole-derived compounds, due to their color characteristics, are promising candidates for use in the latest lighting systems. A separate advantage of the data light-emitting structures is a multifunctional application of one compound for different types of light-emitting structures. In addition, organic LEDs on based on carbazole-derived compounds have low energy consumption and are environmentally friendly due to the absence of toxic substances in their architecture, which creates prerequisites for saving energy resources and reducing the industrial burden on the environment.

Large pyroelectric energy conversion in lead scandium tantalate thin films

Non-linear pyroelectric energy harvesting using ferroelectric thin films exhibits high energy conversion, primarily due to their large breakdown field compared to bulks. Here, we report the pyroelectric energy conversion potential of lead scandium tantalate, Pb(Sc1/2Ta1/2)O3 (PST) thin film fabricated on a c-sapphire substrate using chemical solution deposition. To enable the application of high electric field and to assess the pyroelectric energy conversion performance, interdigitated electrodes were deposited on the PST thin film. A maximum harvested energy density of 9.1 J cm−3 per cycle was deduced from polarization measurements in films undergoing an Olsen cycle between 0 °C and 150 °C when the electric field was varied between 50 and 1500 kV/cm. Furthermore, PST thin films can reach up to 27 % of Carnot efficiency for a temperature interval of 10 K between 30 °C and 40 °C. This study highlights the significance of PST thin films for electro-thermal energy harvesting and promising opportunities for enhancing the conversion efficiency and power density using thin films or thin film multi-layer capacitors in the future for thermal energy harvesting.

Investigating mechanism of photo refractivity in Mg substituted ZnO thin films using pump and probe technique

In the current investigation magnesium (Mg) has been incorporated in the ZnO matrix to induce photo refractivity thereby adding an extra dimension to its already present multi-functionality. Undoped and MgxZn1-xO (x = 0.25, 0.30, 0.35, 0.40, 0.45) thin films have been grown using Chemical Solution Deposition (CSD) technique. Obtained X-Ray Diffraction (XRD) spectra exhibits a slight shift in the peak value along (002) plane whereas UV–visible spectra indicates corresponding widening of ZnO band gap values (3.24–3.64 eV) with increase in Mg content. Mg substituted ZnO films were then investigated for their ferroelectric properties using a P-E hysteresis loop tracer. It was noted that ZnO film with 35 % Mg content (x = 0.35) exhibited the high values for saturation (Ps = 1.8 μC/cm2) and remnant (Pr = 0.7 μC/cm2) polarization. Hence the ZnO with same Mg concentration was investigated for nonlinear optical properties (two wave mixing phenomenon) using pump and probe technique. In order to enhance the beam amplification gain and impart stability Au micro-dots were thermally evaporated onto MgxZn1-xO (x = 0.35) films. The maximum beam amplification gain was noted to shoot up to 2.7 post patterning of MgxZn1-xO (x = 0.35) film surface by Au micro-dots.

Methyl-ammonium lead iodide hybrid perovskite thin film as active material for energy conversion devices

The use of hybrid halide Perovskites is helping us get closer to our aim of completely selfsufficient structures in terms of energy production. Preparation of a device of photoactive material CH3NH3PbI3 {FTO (Fluorine-doped tin Oxide)/ CH3NH3PbI3/SpiroOMeTAD/Al} for the photovoltaic applications has been described in this article. Producing a homogeneous thin film through the use of lower temperature, processedsolution devices with one-step spin coating processes is an essential stage in the fabrication process. To generate the thin films on the FTO-substrate, the one-step spin coating approach was utilized for the deposition of the precursor solution, which consisted of methylammonium iodide and lead iodide in a molar ratio of 3:1. This technique was employed to prepare the thin films. The FESEM technique was utilized to carry out the investigation of the surface morphology of this thin layer. In addition, the essential parameters of this device, like barrier height, saturation current, current density, ideality factor, carrier mobility, resistance, carrier lifetime, and capacitance have been computed using current-voltage (I-V) characteristics and the impedance spectroscopy technique. A laser with a power of 20 milliwatts and a wavelength of 532 nanometers was used to light the gadget. The current conduction mechanism exhibits ohmic behavior at a low voltage, while at medium voltages, TFSCLC is the mechanism that regulates charge transportation. Despite the fact that TCSCLC is demonstrated at higher voltages. The TCSCLC model was used to conduct an investigation of the hole's mobility.

A New Method for Analysis of Martials Nano and Micro Electronics Technologies

This final qualifying work investigates prospective microelectronic and nano electronic materials. The purpose of the final qualifying mission is to evaluate potential manufacturing technologies and materials. In the first phase of the endeavor, potential materials for microelectronics and nanoelectronics were investigated. Graphene, fullerenes, fullerites, carbon nanotubes (CNT), nanofibers, ferrites, barium hexaferrite, nano powders, and epitaxial coatings are among these substances. An investigation into diverse methodologies pertaining to the production of auspicious materials was undertaken during the preliminary stage of the undertaking. Molecular beam epitaxy, pulsed laser deposition, spray deposition, physical vapor deposition (PVD), chemical solution deposition, gas-phase synthesis, electrospinning, chemosynthesis, detonation synthesis and electric explosion, chemical vapor deposition (CVD), spray deposition, physical vapor deposition (PVD), and the sol-gel method were among these processes.

Exploring secondary optical transitions: a study utilizing the DITM method, and enhanced photocatalytic properties in Ni-doped CuSe

This study explores the simultaneous presence of two metal ions of Nickel (Ni) and Copper (Cu) on the formation of a metal selenide (Ni-doped CuSe) in an alkaline environment. The impact of Ni ions on creating the second optical transitions is investigated. Different concentrations amounts of Ni ions (0.01, 0.02, and 0.03 mol) are utilized to produce Ni-doped CuSe semiconductor thin films through a chemical solution deposition method with deposition times varying from 3 to 6 h. Absorbance spectra are employed to determine the band-gap, while Field Emission Scanning Electron Microscopy is utilized for morphological analysis. Structural and elemental analyses are conducted using X-ray Diffraction and Energy Dispersive X-ray Spectroscopy techniques. Additionally, a relatively innovative approach for determining the optical transitions, termed the Derivation Ineffective Thickness Method (DITM), is employed. DITM eliminates the need for thin film thickness and assumptions about the type of transition (direct or indirect) for band-gap calculation. Moreover, a comparison is made between the band-gap obtained from the Tauc model and the transitions obtained by DITM method. Furthermore, it is demonstrated that the optical transitions exhibit two distinct band-gaps associated with nickel selenide (NiSe) as second transition and copper selenide (CuSe) as fundamental transition. The presence of Ni is also found to enhance crystal quality. The study also briefly explores the improved photocatalytic properties of CuSe in the presence of Ni.

Development of a 3D point cloud reconstruction-based apple canopy liquid sedimentation model

China leads the world in apple production, contributing to over half of the global total. Annually, extensive pesticide use is employed in apple cultivation, but the uncertain quantities of pesticide deposition and indiscriminate application have resulted in significant pesticide loss and residue. This poses a considerable potential risk to human health. This paper focuses on ground-based plant protection and stratifies the canopy horizontally, using 3D point cloud reconstruction technology and tree deposition experiments to explore the relationship between canopy leaf area index and pesticide deposition. By calculating the droplet penetration coefficient based on the amount of solution deposited at various canopy layers, a functional model linking leaf area index and droplet penetration coefficient has been established, with a correlation coefficient (R2) of 0.92. Based on this model, and by integrating the canopy volume with the amount of solution deposited on the outermost layer of the canopy, the total solution deposition on the entire tree can be estimated. According to the deposition model, there is a negative correlation between the amount of solution deposited on the canopy and the leaf area index of the canopy. Moreover, the experiments have shown that when the spray vehicle travels at a speed of 1.5 m/s, the maximum amount of solution is deposited while still ensuring an effective deposition rate. The establishment of the deposition estimation model allows for the visualization of canopy solution deposition and can guide fruit farmers in determining the appropriate frequency of spraying based on the severity of pest and disease infestations.

Visualization of oxygen vacancies at CeO x /Y-HZO interface by spectrum imaging method and multivariate analysis

Electron energy loss spectroscopy—spectrum imaging measurements using a scanning transmission electron microscope are carried out to clarify the details of microstructure at the interface of the CeO x -capped Y-HZO film prepared by the chemical solution deposition (CSD) method. We confirmed that by the present CSD the independent capped layer of CeOx successively deposited on Y-HZO. The crystal structure of CeO x film is mainly the cubic CeO2 structure with Ce4+. Chemical state maps are also successfully obtained by the multivariate analysis. We found that Ce3+ and Ce4+ coexist in the interface layer with cubic CeO2 crystal structure containing O vacancy. The results of the quantitative elemental distribution maps of energy dispersive X-ray spectroscopy also supported that O vacancies exist at the interface.

Effecting on electrical performance of Methylammonium Lead Chloride Iodide perovskite films composited by reduced graphene oxide for controlling double Schottky barrier

Semiconducting perovskite thin films are cheap to fabricate and can be coated on fluorine-doped tin oxide (FTO) substrates by using simple techniques such as the solution deposition method. In this work, we show that the improved electrical performance of perovskite film produces that of single crystals in an ambient atmosphere. Herein, Methylammonium Lead Chloride Iodide (MAIPbCl2) is played as perovskite films, which were composited with different weight percent (wt%) of rGO from 7 to 10. All samples in this work were presented with physicochemical, electrical, and optical properties. However, the challenge of this work is the electron scattering at the grain boundaries as a result of the double schottky barrier. The best decreasing the double schottky barrier yielded a maximum conductivity of 68.72 ± 0.95 S/cm, a low sheet resistance of 5.47 ± 1.64 Ω, a decrease in the lowest oxygen vacancy, and an increase in the grain size from 27.89 nm (of MAIPbCl2) to 34.96 nm at room temperature for the MAPbCl3-8 wt% rGO composite, which also revealed that this strategy significantly helped to improve the performance of the film. Furthermore, temperature dependence for MAIPbCl2-rGO composites demonstrates this high electrical conductivity from room temperature to 323 K, with highest electrical conductivities of 78.68 ± 0.01 S/cm and the activation energy of 0.18 eV at 313 K for 8 wt% rGO. Therefore, MAIPbCl2-rGO composite films demonstrated the enhancement of performance of MAIPbCl2 films; this is next promising for perovskite films in the future.

Development of an automated and cost-effective apparatus for sol-gel solution deposition using spray coating technique and its application for TiO[formula omitted]-based photocatalytic films

This study presents the development of a novel apparatus for automated sol–gel solution deposition through a cost-effective spray coating technique. The focus was on producing TiO2 films for photocatalytic applications, addressing environmental pollution and energy scarcity issues. The apparatus, constructed using economical materials, facilitated the production of TiO2 films with an anatase-like crystalline structure and uniform surface morphology. The methodology included detailed experimental procedures for solution preparation, substrate cleansing, and deposition process optimization. Characterization techniques such as scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FTIR), and UV–Vis spectroscopy were employed to assess the structural, morphological, and optical properties of the films. The results indicated the successful synthesis of anatase-phase TiO2 thin films with desirable optical properties and efficient photocatalytic activity, as demonstrated through the degradation of methylene blue and methyl orange. The study highlights the apparatus’s efficiency, versatility, and potential for industrial-scale production, thus offering promising prospects for practical applications and commercialization in the field of sustainable environmental solutions.