Soda-lime Glass Substrates Research Articles

Effect of precursor concentration on stoichiometry and optical properties of spray pyrolyzed nanostructured NiO thin films

In this study, spray pyrolysis was used to produce nanostructured NiO thin films from high purity nickel acetate (Ni(CH3COO)2.3H2O) precursors on pre-heated ultrasonically cleaned soda-lime glass substrates. The metallic constituent concentrations in the films were varied, and the precursors were produced in distilled water at various molarities ranging from 0.1 to 0.4 M. In the study, the field-emission scanning electron microscope (FESEM) results strongly confirmed adherence of the films to the glass substrate at 350 °C. The presence of Ni and O in the samples was confirmed using Rutherford backscattering spectroscopy (RBS), X-ray diffractometry (XRD) and energy dispersive X-ray spectroscopy (EDX). For the 0.1 M NiO thin films, the thickness was approximately 43 nm, and for the 0.2 M, 0.3 M, and 0.4 M films, the thickness was 46 nm, 47 nm, and 49 nm, respectively. The XRD findings were supported by the increased Raman intensity peaks with increased precursor concentration, which confirmed the films' improved crystallinity. For the same number of passes of films deposition, as the molar concentration increases, the films thickness increases. The amount of nickel in NiO thin films increases as the molarity increases, but the amount of oxygen in NiO thin films decreases as the molarity increases. It was discovered that as molarity increases, the optical transmittance decreases and the optical band gap narrows. The qualities of NiO discovered in this study suggest the films’ potentials for usage as window layer and buffer material in thin film solar cells.

Design of experiments optimization of fluorine-doped tin oxide films prepared by spray pyrolysis for photovoltaic applications

Transparent conducting oxides (TCOs) have witnessed an ever-expanding use in our lives through many optoelectronic applications, namely photovoltaic (PV) devices. Indium-tin oxide (ITO) is the most used and studied TCO, but it lacks thermal and chemical stability and indium is a scarce and toxic element. Fluorine-doped tin oxide (FTO) emerged as the most promising alternative to ITO, presenting better thermal and chemical stability. Among the numerous techniques for depositing FTO thin films over glass substrates, spray pyrolysis is the simplest and most economical, with great potential for upscaling. However, the relative importance of the experimental variables that influence the optoelectronic properties remains barely addressed. Following this premise, the present work aimed at optimizing the deposition of FTO films on soda lime glass (SLG) substrates by spray pyrolysis following a Design of Experiments (DoE) methodology. The optoelectronic properties of FTO-SLG substrates was evaluated based on their optical transmittance and sheet resistance, both combined in a figure of merit (FoM) tailored for PV applications. It was concluded that the volume of sprayed solution and the fluorine/tin ratio in the precursor have the greatest influence in the FoM, being the optimal deposition conditions a sprayed volume of 60.8 ml and a [F]/[Sn] ratio of 0.45. FTO-SLG substrates prepared with these conditions achieved a FoM of 0.680 Ω□−1/10, corresponding to a sheet resistance of 3.40 Ω□ and a transmittance equivalent to 77% of the maximum current generated in the considered spectrum. The improved FoM was validated in dye-sensitized and perovskite solar cells (DSSCs and PSCs, respectively), assembled with in-house optimized and commercial substrates. The efficiency of DSSCs was improved by 8.9% (relative), whereas PSCs achieved a light-to-power efficiency of 17% (absolute), corresponding to an improvement of 4.7% (relative).

Electrical Characterization of Chemically Grown CdS and CdTe Thin Films for Solar Cell Application

Thin films of Cadmium Sulphide (CdS) and Cadmium Telluride (CdTe) have gained a great deal of interest due to their potential applications in solar cells. Deposition of CdS and CdTe thin films were performed on Soda Lime glass and FTO substrate at 400℃ and 300℃ respectively using spray pyrolysis technique. The Hall Effect property was measured for the deposited CdS and CdTe films. These results shows the resistivity and mobility of CdS films deposited at 400℃ were 1.588×104 Ωcm and 5.619×102 cm2/Vs, respectively, The annealed CdTe thin film had a resistivity value of 1.016×104 Ωcm, while the annealed and etched CdTe thin film had a resistivity value of 4.52×104 Ωcm, The resultant films are observed to be good to make a solar cell with CdS as a window layer and CdTe as absorber layer.

Comparison of Sputtered and Evaporated Vanadium Pentoxide Thin Films for Resistive Microbolometer Application

V2O5 thin films have made impressive progress in the development of resistive microbolometers. The challenging parameters for microbolometers are the active material selection and the deposition methods. It might be a more promising way to achieve a good performance of the devices. The present work deals with the V2O5 thin films fabricated on soda lime glass substrates by using e-beam evaporation and magnetron sputtering techniques at a substrate temperature of 200 °C. Afterward, samples were annealed at 300 and 400 °C for 1 h to obtain uniform and stoichiometric thin films. X-ray Diffraction (XRD) showed that the thin films deposited by magnetron sputtering were amorphous in nature, even after annealing at elevated temperatures; however, the thin films fabricated by the electron beam evaporation technique show crystalline nature, which was improved by annealing. XRD also revealed various mixed phases of VOx in electron beam-deposited films. Optical properties were determined using UV-Visible spectroscopy, which showed a decrease in transmittance from 81% down to 57% by increasing the annealing temperature. Similarly, the band gap calculated for electron beam evaporated and magnetron sputtered V2O5 thin films was observed in the range of 1.41 to 2.25 eV. Rutherford backscattering (RBS) was performed to determine the thickness and composition of the films. Slight variations have been observed in intended and deposited thicknesses of films fabricated by e-beam and sputtering techniques. Structural properties revealed by Field Emission Scanning Electron Microscope (FESEM) were found to be the uniform, compact and dense surface of the as-deposited and 300 °C annealed samples. However, annealing at 400 °C changed the surface morphology into nanorods in e-beam and plate-like structures in the sputtered film. EDS proved the elemental concentration of vanadium and oxygen in these V2O5 thin films. Electrical properties were investigated using the Hall measurement technique which showed better conductivity of sputtered films than e-beam deposited films. It can be concluded that the cost-effective and reliable microbolometers infrared (IR) sensors can be fabricated using annealed sputtered films.

New Formulation to Synthetize Semiconductor Bi2S3 Thin Films Using Chemical Bath Deposition for Optoelectronic Applications

Anisotropic materials possess direction dependent properties as a result of symmetry within their structure. Bismuth sulfide (Bi2S3) is an important semiconductor exhibiting anisotropy due to its crystalline and stratified structure. In this manuscript we present a new and straightforward procedure to deposit Bi2S3 thin films on soda lime glass substrates by the chemical bath deposition (CBD) technique. We studied two fundamental parameters, the time to deposit a single layer and the total number of layers deposited. The single layer deposition time was varied between 70 and 100 min and samples were coated with a total of 1, 2, or 3 layers. It is important to note that a fresh aqueous solution was used for every layer. Visible and near infra-red spectroscopy, scanning electron microscopy, X-ray photoelectrons spectroscopy, and X-ray diffraction were the characterization techniques used to study the resulting films. The calculated band gap values were found to be between 1.56 and 2.1 eV. The resulting Bi2S3 deposited films with the new formulation showed uniform morphology and orthorhombic crystalline structure with an average crystallite size of 19 nm. The thickness of the films varied from 190 to 600 nm in direct correlation to the deposition time and in agreement with the number of layers. The XPS results showed the characteristic bismuth doublet centered around 164.11 and 158.8 eV corresponding with the presence of Bi2S3. The symmetry within the Bi2S3 structure makes it a strong anisotropic crystal with potential applications in optoelectronic and photovoltaic devices, catalysis, and photoconductors among others.

Effect of PAA on the structure and transmittance of hollow spherical SiO2 film prepared by sol-gel method

Hollow spherical silica film has been used on glass substrates as an antireflective coating, and PAA is one of the common templates for preparing SiO2 films by sol-gel method. In this paper, the effects of polyacrylic acid (PAA) content on the SiO2 films prepared by the sol-gel method were analyzed using TEM, DLS, XRD, IR, SEM, and the transmission spectrum. The sol containing hollow spherical micelles can be prepared well from tetraethyl orthosilicate (TEOS) as raw material and PAA as water-soluble polymer by improved Stober, and template method. With the increase of PAA content, the particle size of hollow spherical silica colloidal particles increases and the quantity decreases. The sol is attached to the surface of the soda lime glass substrate to form a film by dip-coating method. With the increase of withdrawal speed, the transmittance of the glass increases, and with the increase of PAA content from 0.1g to 0.6g, the sample's transmittance decreases first and then increases.

Solvothermal treatment of MgF2 coating solutions: a comparative study

MgF2 coating solutions were prepared by the fluorolytic processing of Mg(OEt)2 and MgCl2. Parts of these sols are solvothermally treated in an autoclave at 160 °C. The two respective precursors were used to prepare porous λ/4 antireflective films by dip-coating on soda-lime and borosilicate glass substrates. UV–Vis spectroscopy and X-Ray diffraction (XRD) were applied to characterize the films as a function of annealing temperature. Samples treated at 500 °C underwent testing of abrasion resistance and water solubility.Porous antireflective MgF2 coatings were prepared from as-synthesized solutions and sols that had additionally undergone solvothermal processing. Films prepared on soda-lime and borosilicate glass substrates were systematically compared.

A new route for the synthesis of n-type Ag2ZnSnS4 thin films by thermal vacuum evaporation for solar cell applications

Special interest has been recently devoted to the quaternary material Ag2ZnSnS4 (AZTS) due to its remarkable electrical and optical properties. Our study proposes a new method for the synthesis of Ag2ZnSnS4 thin films by thermal vacuum evaporation on soda-lime glass (SLG) substrates by tuning their thickness. Structural characterization of thin films, performed by X-ray diffraction and Raman spectroscopy, confirmed the presence of the AZTS stannite phase with the appearance of the Ag8SnS6 secondary phase. As the thickness increases, a transition from amorphous to polycrystalline state appears in the XRD spectra, along with an increase in intensity related to a refinement of the preferential peak (112), an increase in crystallite size and a decrease in stress and dislocations. Compositional analysis confirms the stoichiometric composition of the films. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) reveal a strong thickness dependence of the film on the surface structure. Moreover, the thickness affects significantly the optical properties of films. In particular, an increase of the absorption coefficients associated with a decrease of the direct gap energy and the Urbach energy is observed with increasing thickness. The optical and dielectric constants have been studied and discussed in more detail based on the single oscillator model proposed by Wemple DiDomenico and other models. The static refractive indices as well as the static dielectric constant of the layers show a slight increase with layer thickness, in contrast to the oscillator energy. Finally, all samples display n-type conductivity according to the hot probe experiment. Such attractive characteristics can be useful to further improve the efficiency of thin film solar cells by adjusting the thin film thickness.

Effect of 4He2+ ion irradiation on the optical, electrical, morphological, and structural properties of ZnO thin films

A study of the effect of 2.5 MeV 4He2+ ion irradiation on the optical, electrical, morphological and structural properties of ZnO thin films is presented. Polycrystalline zinc oxide thin films were deposited on soda lime glass substrates using the spray pyrolysis technique. During the process, the substrates’ surfaces were kept at 400, 450 and 500 °C. The samples were analyzed by different techniques and the optical results showed a red shift in the energy band gap after irradiation. It was also confirmed that the wurtzite-type hexagonal structure of the ZnO films remained after irradiation, the crystallite size increased and the lattice parameters decreased due to He2+ irradiation. SEM micrographs revealed that ion irradiation favors the nucleation and the formation of grains in the films. Micrographs showed nanometric particles with spherical and flake-like forms, which depend on the deposition temperature. A decrement in the average particle size of the samples deposited at 400 and 450 °C was observed after irradiation; meanwhile, an increase in the particle size was detected in the film deposited at 500 °C. The resistivity values increased with He2+ ion irradiation.

Cu2SnSe3 phase formation from different metallic and binary chalcogenides stacks using magnetron sputtering

Cu2SnSe3 (CTSe) is a polyvalent material that can be used as an absorber layer for thin film solar cells or as a starting layer for the synthesis of CZTSe or CZTSSe compounds. Obtaining CTSe single phase films with optimized properties for thin film solar cells is a difficult task. A systematic study using both metallic and binary chalcogenides precursors for the formation of the CTSe phase was not performed. The films consisting of four different stacks (Sn\\Cu, SnSe2\\Cu, Sn\\Cu2Se, and SnSe2\\Cu2Se) were prepared by magnetron sputtering on soda lime glass (SLG) and molybdenum (Mo) coated SLG substrates, followed by annealing at 550 °C under Sn + Se atmosphere. X-ray diffraction and Raman spectroscopy results indicated the formation of a single CTSe phase in most of the stacks deposited on both substrates. Scanning electron microscopy images showed compact surfaces with large grains in the films deposited on Mo substrate, while the films on SLG have more voids on their surfaces. The elemental analysis measured by energy dispersive spectroscopy revealed stoichiometric films on Mo, and copper and tin rich compositions on SLG substrates. The band gap values inferred by conventional spectroscopy are between 0.81 and 1.95 eV. It was found that the SnSe2\\Cu and Sn\\Cu2Se stacks are preferred for the formation of a single CTSe phase, with dense surface morphology, a stoichiometric composition, and an optimal absorber layer band gap. This study opens the way to comprehend the formation reactions during the selenization of metallic and binary chalcogenides precursors towards the optimization of kesterite absorber for photovoltaic device fabrication.

Effect of annealing temperature on the microstructure and optoelectronic properties of niobium-doped anatase TiO2 thin films grown on soda-lime glass substrate

Effect of annealing temperature on the microstructure and optoelectronic properties of niobium-doped anatase TiO2 thin films grown on soda-lime glass substrate

Investigating the influence of Ni doping on the CuO thin films deposited via ultrasonic spray pyrolysis: Structural, optical and H2 gas sensing analyses

Pure and nickel doped copper oxide thin films were successfully grown on a soda lime glass substrates including various amounts (1, 2, 4, and 8%) of nickel dopants via ultrasonic spray pyrolysis method. The effects of the different impurity doping concentrations on the structural, morphological, optical, and H2 gas sensing properties of the prepared samples were assessed by performing X-ray Diffraction, scanning electron microscopy, ultraviolet–visible spectroscopy, photoluminescence spectroscopy, gas sensing measurements, and X-ray photoelectron spectroscopy. The structural observations revealed that the grown films have polycrystalline nature with monoclinic cubic crystal structure of copper oxide with no secondary phases present, and grain sizes increased in general as the doping percentage increased except for the 4% nickel doped sample. The morphological analysis showed that the impurities clearly led to modifications in the shapes of the grown copper oxide nanocrystals. In the optical measurements, it was uncovered that the ideal impurity level can enhance the absorbance features of the copper oxide material, and a slight increase in bandgap occurred due to the first level of impurity doping, but then the bandgap decreased as the impurity contents increased. A gradual decrease in the intensity of luminescent emissions was observed in the photoluminescence spectra as the doping concentration increased, which may be associated with the defects caused by the added nickel ions into the copper oxide lattices. Gas sensor measurements disclosed that the produced films were responsive when exposed to H2 gas, and enhanced responsivity was realized by the nickel doping compared to that of pure copper oxide sample. X-ray photoelectron spectroscopy confirmed the presence of aimed chemical compositions in the prepared thin films.

The multi-dimensional characterization of Al-doped CuO thin films by laser-induced breakdown spectroscopy (LIBS) with nanosecond and picosecond lasers

Glasses coated with various optical thin film materials are widely used in people's life and scientific research. In this study, a series of aluminum-doped (Al-doped) copper oxide (CuO) thin films with different sputtering pressures and powers were deposited on soda-lime glass substrates by RF-magnetron sputtering to explore the effect of doping element on the optical properties of the thin films. However, laser-induced breakdown spectroscopy (LIBS) with nanosecond and picosecond lasers was employed to achieve the multi-dimensional analysis of the Al element. With ns-LIBS, the rapid quantitative analysis was performed by drawing the calibration curves of LIBS intensity ratio of Al/Cu versus concentration ratio under different sputtering pressures and powers. Furthermore, the 2D chemical mappings were drawn to provide a more complete and detailed relative spatial distribution of the Al element according to the LIBS intensity ratio of Al/Cu. Meanwhile, the thin film thickness was determined by the picosecond laser pulse number since the depth ablated by a single laser pulse was assessed as nearly 46.75 ± 4.25 nm. Moreover, the variation trends of optical band gaps with sputtering parameters were similar to that of LIBS intensity ratios with sputtering parameters, as suggested by analyzing the transmission spectra of thin films. The results demonstrated that the multi-dimensional characterization (quantitative analysis, 2D chemical mapping, thin-film thickness estimation, and optical properties analysis) of Al-doped CuO thin films prepared by RF-magnetron sputtering can be effectively realized by LIBS.

Effect of tungsten doping on the microstructure, optical and photocatalytic activity of titanium dioxide thin films deposited by spray pyrolysis

In this study, pristine titanium dioxide (TiO2) and tungsten (W) doped TiO2 (W: TiO2) thin films with concentrations of 2, 4, 6 and 8 at. % has been deposited on a soda lime glass substrate at 450 °C using a simple spray pyrolysis (SP) technique. The surface morphology of TiO2 and W: TiO2 thin films showed a mixed phases of particle and reticulated fiber nature as observed by the field emission scanning electron microscopy (FESEM). The average size of the particles was found to be 1.094 μm and the thickness of the reticulated fiber varies between 0.230 and 0.651 μm. Energy dispersive X-ray (EDX) analysis demonstrate stoichiometric distribution of Ti, W, and O elements in the as-deposited films. Ultraviolet–visible (UV–Vis) spectroscopy was used to estimate the optical band gap of the thin films and was found to be decreased monotonically from 3.36 eV to 3.02 eV due to the incorporation of W into the TiO2 thin films. The effect of W-doping on the variation of edge potentials of the conduction bands (CB) and valence bands (VB) of the TiO2 thin films were studied. Furthermore, the effect of W-doping on the degradation of the methylene blue (MB) under UV-light illumination was studied. 6 at. % W: TiO2 thin films demonstrate the highest degradation efficiency (76%) among all the samples. This can be attributed to the reduction of electron-hole recombination due to reduced band gap together with production of adsorption sites at the cylindrical pores of the thin films.

Optimal thickness and annealing temperature for enhancement of structural, optical, and photocatalytic properties of ZnO thin films

Thin films of ZnO, with distinct thicknesses, were deposited on soda-lime glass substrates by sol–gel spin-coating as a cost-effective method without any evacuation facilities. The nanocrystalline structure of the deposited films was indexed by the atomic force microscope and X-ray diffraction techniques. The average grain size increases with the increase of the film thickness and annealing temperature. The energy-dispersive X-ray technique has been used to check the atomic ratios of Zn and O with the film thickness and heat treatment for homogeneous ZnO films. ZnO films show elevated transmission in the visible spectrum as a transparent semiconductor material. Optical constants, like absorption coefficient, optical band gap, and refractive index, were obtained by the Swanepoel method. All thin film samples were applied for photodegradation of reactive orange 96 (RO96) to evaluate the effect of thickness and annealing temperature on the ZnO film’s photocatalytic activity. ZnO 4L (400 °C, 3 h) film possesses the highest rate of photodegradation about 0.1 min−1 for RO96 with high stability and reusability.

PbS and PbO Thin Films via E-Beam Evaporation: Morphology, Structure, and Electrical Properties.

Thin films of lead sulfide (PbS) are being extensively used for the fabrication of optoelectronic devices for commercial and military applications. In the present work, PbS films were fabricated onto a soda lime glass substrate by using an electron beam (e-beam) evaporation technique at a substrate temperature of 300 °C. Samples were annealed in an open atmosphere at a temperature range of 200–450 °C for 2 h. The deposited films were characterized for structural, optical, and electrical properties. Structural properties of PbS have been studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and Rutherford backscattering spectrometry (RBS). The results of XRD showed that the PbS thin film was crystalline in nature at room temperature with cubic crystal structure (galena) and preferential (111) and orientation (022). The morphology of the thin films was studied by FESEM, which also showed uniform and continuous deposition without any peel-off and patches. EDS analysis was performed to confirm the presence of lead and sulfur in as-deposited and annealed films. The thickness of the PbS film was found to be 172 nm, which is slightly greater than the intended thickness of 150 nm, determined by RBS. Ultraviolet-Visible-Near-Infrared (UV-Vis-NIR) spectroscopy revealed the maximum transmittance of ~25% for as-deposited films, with an increase of 74% in annealed films. The band gap of PbS was found in the range of 2.12–2.78 eV for as-deposited and annealed films. Hall measurement confirmed the carriers are p-type in nature. Carrier concentration, mobility of the carriers, conductivity, and sheet resistance are directly determined by Hall-effect measurement. The as-deposited sample showed a conductivity of 5.45 × 10−4 S/m, which gradually reduced to 1.21 × 10−5 S/m due to the composite nature of films (lead sulfide along with lead oxide). Furthermore, the present work also reflects the control of properties by controlling the amount of PbO present in the PbS films which are suitable for various applications (such as IR sensors).

Subaquatic indirect laser ablation technique for glass processing.

Subaquatic indirect Laser-Induced Plasma-Assisted Ablation (SLIPAA) is proposed as a laser-based technique for glass processing. In this configuration, a water layer is added between a metallic target and a soda-lime glass substrate, so the processing of the glass is due to a combination of the ablation mechanism, the shock waves, and the cavitation bubbles. Thus, this method makes it possible to produce higher depth structures than those performed up to now by other standard laser techniques based on ablation, achieving structures in glass with rectangular cross-sectional profiles. Channels of 1 mm width are fabricated, reaching an average maximal depth value of almost 1400 µm at 30 passes of the laser beam while keeping the focal position fixed. Furthermore, the difference between processing the material with and without the addition of the water layer is presented. The influence of the processing parameters on the shape and quality of the fabricated structures is studied by optical and confocal microscopy, microcomputed tomography, and scanning electron microscopy. Compositional analysis of the glass is performed by energy dispersive X-ray technique to assess the transference of material from the metallic target to the fabricated channels. Deeper and more complex structures are obtained by refocusing the laser beam on the target and adding a pulsed flowing water film.

Study the optical parameters of aluminum doped ZnS films deposited on soda-lime glass substrate

Zinc Sulfide (ZnS) thin films have gained popularity due to their potential field applications. ZnS doped with various elements is redefining academic and industrial research. Pulsed laser deposition (PLD) was applied in the deposition process of undoped ZnS and aluminum (Al) doped zinc sulfide (AZS) on cleaned soda lime glass substrates. The doping effects of aluminum concentration (0, 2, 4, and 6%) on the characteristics of ZnS films were investigated. The ZnS and AZS thin films exhibited a direct allowed bandgap in the range of 3.40 to 3.56 eV, The band gap has been observed to be higher (3.56 eV) indicating blue shift. The linear optical parameters such as oscillator energy (E0), dispersion energy (Ed), and static refractive index (n0) were calculated using Wemple and DiDominco's model to find the nonlinear optical susceptibility χ 3 and nonlinear refractive index n2. The increasing nonlinear parameters χ 3 and n2 suggest nonlinear optical applications for AZS. The experimental methods and results are described, and the results are compared to published data.

Synthesis of High Quality Transparent Nanocrystalline Diamond Films on Glass Substrates Using a Distributed Antenna Array Microwave System

Diamond is a material of choice for the fabrication of optical windows and for protective and anti-reflecting coatings for optical materials. For these kinds of applications, the diamond coating must have a high purity and a low surface roughness to guarantee a high transparency. It should also be synthesized at low surface temperature to allow the deposition on low melting-point substrates such as glasses. In this work, the ability of a Distributed Antenna Array (DAA) microwave system operating at low temperature and low pressure in H2/CH4/CO2 gas mixture to synthesize nanocrystalline diamond (NCD) films on borosilicate and soda-lime glass substrates is investigated aiming at optical applications. The influence of the substrate temperature and deposition time on the film microstructure and optical properties is examined. The best film properties are obtained for a substrate temperature below 300 °C. In these conditions, the growth rate is around 50 nm·h−1 and the films are homogeneous and formed of spherical aggregates composed of nanocrystalline diamond grains of 12 nm in size. The resulting surface roughness is then very low, typically below 10 nm, and the diamond fraction is higher than 80%. This leads to a high transmittance of the NCD/glass systems, above 75%, and to a low absorption coefficient of the NCD film below 103 cm−1 in the visible range. The resulting optical band gap is estimated at 3.55 eV. The wettability of the surface evolves from a hydrophilic regime on the bare glass substrates to a more hydrophobic regime after NCD deposition, as assessed by the increase of the measured contact angle from less than 55° to 76° after the deposition of 100 nm thick NCD film. This study emphasizes that such transparent diamond films deposited at low surface temperature on glass substrate using the DAA microwave technology can find applications for optical devices.

NaCl-Assisted Chemical Vapor Deposition of Large-Domain Bilayer MoS2 on Soda-Lime Glass.

In recent years, two-dimensional molybdenum disulfide (MoS2) has attracted extensive attention in the application field of next-generation electronics. Compared with single-layer MoS2, bilayer MoS2 has higher carrier mobility and has more promising applications for future novel electronic devices. Nevertheless, the large-scale low-cost synthesis of high-quality bilayer MoS2 still has much room for exploration, requiring further research. In this study, bilayer MoS2 crystals grown on soda-lime glass substrate by sodium chloride (NaCl)-assisted chemical vapor deposition (CVD) were reported, the growth mechanism of NaCl in CVD of bilayer MoS2 was analyzed, and the effects of molybdenum trioxide (Mo) mass and growth pressure on the growth of bilayer MoS2 under the assistance of NaCl were further explored. Through characterization with an optical microscope, atomic force microscopy and Raman analyzer, the domain size of bilayer MoS2 prepared by NaCl-assisted CVD was shown to reach 214 μm, which is a 4.2X improvement of the domain size of bilayer MoS2 prepared without NaCl-assisted CVD. Moreover, the bilayer structure accounted for about 85%, which is a 2.1X improvement of bilayer MoS2 prepared without NaCl-assisted CVD. This study provides a meaningful method for the growth of high-quality bilayer MoS2, and promotes the large-scale and low-cost applications of CVD MoS2.