Glass Slide Substrates Research Articles

The effect of nanobubbles on Langmuir-Blodgett films

Nanobubbles (NBs) are classified in two distinct categories: surface and bulk. Surface NBs are readily observed using atomic force microscopy (AFM), while the existence of bulk NBs has been a subject of debate, conflicting with the diffusion theory's predictions. Current methodologies for identifying bulk NBs yield inconclusive results. In this study, Langmuir Blodgett (LB) technique and AFM, are utilized to visualize NB imprints on anionic, cationic and zwitterionic lipid films deposited on glass-slide substrates. Our analysis of Langmuir monolayers compression isotherms reveals the impact of bulk NBs on lipid monolayer development. AFM scans of the deposited lipid films consistently show NB imprints. Notably, cationic and zwitterionic film depositions exhibit NB formations from the 1st layer, whereas in anionic films, these formations are observed only after the 3rd layer. These results suggest that the origin of these imprinted formations may be attributed to bulk NBs.

Unveiling the optoelectronic characteristics of SnTe thin films: An extensive investigation via structural & photoresponse analysis of drop-cast deposition

Thin film on a glass slide substrate of tin telluride (SnTe) is deposited at room temperature by drop casting method. The thin films are thoroughly characterized. The study by diffraction of X-ray and Raman stated the crystalline structure and SnTe phase of the films. The films have a cubic structure with space group of Fm-3m. The Raman spectrum showed A1 and ETO vibration modes corresponding to SnTe. The microstructure study is done by optical and scanning electron microscopy. The atomic force microscopy stated the thin film to be flat having uniform even spread. The transmission electron microscopy at high-resolution supported the crystalline nature of the thin films. The spacing of fringes matched the SnTe primary crystallographic (200) plane spacing. The photoresponse of the SnTe thin film is investigated at three intensities keeping +50 mV biasing voltage. The photoresponse analysis showed the drop-casting deposited SnTe thin film offers potential for future applications.

Comparison of properties of multilayer film sputtered on glass and polypropylene substrates with angular DC magnetron Co-sputtering system

Complex multilayer film structures were fabricated through a custom-built angular DC magnetron co-sputtering system. In this system, separate Cu, Al, and brass (Cu + Zn) targets were mounted on three magnetron guns, working in conjunction with a rotating substrate. This study aimed to compare the properties of films with intricate structures, which were sputtered onto glass slides and polypropylene substrates. The sputtering process was optimized using a Box–Behnken design, considering three variable operating conditions: substrate rotation speed, sputtering time, and sputtering voltage. The Analysis of Variance (ANOVA) results for film thickness and roughness, sputtered with three different materials onto glass slides and polypropylene (PP) substrates, indicated that all three independent variables significantly influenced the optimum response, with P-values less than 0.05 (<α = 0.05). The optimal conditions for maximizing the thickness and roughness of the sputtered film on PP substrates differed from those obtained for the thin-film properties of the sputtered film on glass slide substrates. Top-view images of the surface morphology revealed a dense and granular structure for the film deposited on the glass slide, whereas some grooves between the grains and fractures were observed in the film on the PP substrate.Additionally, it was evident that these sputtered multilayer films exhibited a complex structure, as reflected in the uniform and homogeneous distribution of Cu, Al, and Zn atoms on both glass slides and PP substrates.

The temporal response of inorganic temperature-sensitive phosphor films with different layer thickness and composition

The temperature-sensitive paint (TSP), one of the temperature measurement techniques, is useful to evaluate temperature from a cryogenic temperature to a high temperature over 1000°C. An inorganic phosphor TSP was painted on a micro scale indium tin oxide (ITO) heater on a slide glass substrate. The temporal response of TSP to a short heating pulse from the micro-scale heater was estimated by using experimental data and numerical simulation. Measuring the temporal delay using the ITO heater with a micro-scale width and the TSP with a micro-scale thickness necessarily requires data acquisition with high temporal and spatial resolution. In this study, an extremely high spatio-temporal resolution, a temporal resolution of 200 kHz and a spatial resolution of 1.05 μm/pixel, was achieved by using a high-speed camera. We assume that the tendency of temperature at bottom of the TSP which contacts with the ITO is the same as the tendency of the current signal applied to the ITO, and the tendency of surface temperature of the TSP reversely follows the tendency of the phosphorescence signal due to the thermal quenching effect. The time delay was defined as the time difference between the time when the current signal becomes maximum and the time when the phosphorescence signal becomes minimum. Based on the definition of the time delay, the time delay was successfully calculated from the experimental data. The shortest time delay is 30.86 μs which is sufficient to visualize highly dynamic phenomena such as boiling flow. The current signal was employed as a boundary condition for numerical simulation of the one-dimensional heat conduction equation, and the time delay was calculated numerically based on the definition of time delay. The experimentally obtained time delay was compared to the numerically calculated time delay. The results showed that experimentally obtained time delay is longer than expected. Several factors explain the reason why the experimental results are different from expected. The quantitative evaluation of time delay of the fast response TSP for a high temperature measurement was successfully implemented, and the results will play an important role as a first step in understanding the thermo-physical properties of the TSP.

Structural and thermal study of CuInSe2 films

Ternary copper indium Di-selenide (CISe) thin film has been deposited by spin-coating on non-conducting glass slide substrates and a solution prepared by the sol-gel process. At room temperature, correspondingly, CuCl2·2H2O, InCl3·3H2O, and H2SeO3 were employed as precursor source chemicals for Cu, In, and Se ions. The dark brown films adhered effectively to the glass substrates. Energy dispersive X-ray analysis is utilized to assess the thin film's chemical composition, which revealed that the film was close to the stoichiometric ratio and proved the proper elemental composition. The thin film's tetragonal unit cell structure was validated by XRD analysis, and all of the derived lattice parameters (a = 5.8512 A and c = 11.7268 A) are excellent consistent with the previous results. Scherrer's formula yields a crystallite size of 5.94 nm. SEM microtopography of the film surface revealed that the film is homogeneous on the substrate surface, and AFM revealed that the film has a spike-like morphology. UV–Vis spectroscopy was performed in the 300–1400 nm region. The obtained values of the absorption coefficient and band gap are 1.2eV. The thermal analysis is carried out by TGA.

Effect of annealing time on copper selenide thin films prepared by chemical bath deposition

Copper selenide (Cu2Se) thin films have been deposited on glass slide substrates using the chemical bath deposition technique at room temperature. The films were annealed at 250 °C in an air atmosphere at different time intervals. The X-ray diffraction revealed that the Cu2Se films have a face-centered berzelianite cubic structure. The estimated average crystallite sizes were found to be 45 nm. X-ray Photoelectron Spectroscopy showed binding energy peaks corresponding to the Cu2Se. Scanning electron microscopy results showed that the morphology of the Cu2Se thin films consists of spherical particles. Energy dispersive spectroscopy confirmed the presence of Cu and Se. The Ultraviolet–visible spectroscopy results showed that the energy bandgap of the films ranges between 1.52 and 1.25 eV. Photoluminescence results showed emissions from the Cu2Se defects at around 2.27, 2.40, 2.68, and 2.96 eV. It was found that the emission intensity increased up to 3 h and then decreased with an increase in annealing time.

A study of the electrical and optical properties of AZO thin film by controlling pulse frequency of HiPIMS

The transparent conductive oxide (TCO) which is AZO thin film was prepared by controlling pulse frequency at 100 Hz to 900 Hz using high-power impulse magnetron sputtering (HiPIMS). All samples were deposited on silicon (100) and glass slide substrates which the thickness was kept constant at 400 nm. The surface morphology was investigated by field-emission scanning electron microscope (FE-SEM), crystallinity by Grazing Incidence X-ray Diffraction (GI-XRD), optical transparency by UV-Vis-NIR spectrophotometry, and electrical properties using Hall effect instrument. It was found that the AZO films exhibited dense columnar structure. The GI-XRD patterns of AZO films demonstrated the crystal growth direction which was preferred the hexagonal wurtzite structure at (002) and (103) planes. The AZO film prepared by using 700 Hz of frequency (duty cycle 7%) showed the average visible transmittance (Tavg) at 82% in the visible region (380 nm to 780 nm). Additionally, the resistivity, high mobility and carrier concentration of AZO film were found to be 3.0 × 10-3 Ω.cm-1, 10.53 cm2∙Vs-1 and 1.82 × 1020∙cm-3, respectively. The fabrication of AZO film presented excellent electrical and optical properties which could be applied in several optoelectronic applications.

Enhancement of lossy mode resonance sensing properties by the introduction of an intermediate low-refractive-index layer.

Devices based on the lossy mode resonance (LMR) effect have found numerous sensing applications. Herein, the enhancement of the sensing properties by the introduction of an intermediate layer between the substrate and the LMR-supporting film is discussed. Experimental results for a silicon oxide (SiO2) layer of tuned thickness between a glass slide substrate and a thin film of titanium oxide (TiO2) prove the possibility of significantly increasing the LMR depth and the figure of merit (FoM) for refractive index sensing applications, which is supported by a numerical analysis using the plane wave method for a one-dimensional multilayer waveguide. The application of the intermediate layer allows the introduction of a new, to the best of our knowledge, degree of freedom into the design of LMR-based sensors, resulting in improved performance for demanding fields such as chemical sensing or biosensing.

Electrical and Optical Properties of Boron Doped Zinc Oxide Thin-film Deposited by Metal-organic Chemical Vapour Deposition for Photovoltaic Application

Globally, there is a high demand for clean, sustainable and renewable energy for domestic and industrial use. Conventional photovoltaic cell technology relies heavily on crystalline silicon wafers which render silicon-based solar cells expensive due to the initial cost of production and required complex deposition methods. Due to these challenges, great research interest is now directed towards thin-film solar cells. In this work, the metal-organic chemical vapour deposition (CVD) method was chosen in the preparation of boron-doped zinc oxide (ZnO: B) thin film onto a glass slide substrate. The prepared ZnO: B thin films were characterized and optimized as a window layer for solar light trapping. The transmittance of the ZnO: B films varied between 70% and 81% for boron concentration ranging from 0.0 M to 0.06 M. With the increase in boron concentration, bandgap and resistivity of the ZnO: B varied from 2.96 to 3.72 eV and 120 Ω-cm to 58 Ω-cm, respectively. Based on the results obtained, we believe that ZnO: B is suitable as a window layer for solar light trapping in the fabrication of a photovoltaic cell.

Fabrication and Characterization of Ag–Ta Thin Films by Co-Magnetron Sputtering as Alternative Layer for High Reflection of NIR Radiation

Silver–tantalum (Ag–Ta) thin films were fabricated by magnetron co-sputtering on silicon (Si) wafer (100) and glass slide substrates at room temperature. The Ag–Ta thin films were prepared at various deposition times of 5, 10, 20 and 30 s and the physical, structural and optical properties of the Ag–Ta thin films were investigated. It was determined that the thicknesses of the films were 7, 9, 17 and 33 nm, respectively. The results revealed that an increase in the film thickness leads to a monotonic increase in FCC and BCC phase of Ag and Ta, respectively. The work function and stoichiometric of the Ag–Ta thin films were investigated by ultraviolet and X-ray photoemission spectroscopies (UPS and XPS), respectively. The potential of Ag–Ta thin films to be used as low-emission coating was investigated using a spectrophotometer. A UV–VIS–NIR spectrophotometer was used to measure the spectral reflectance in the wavelength range from 300 to 2000 nm. The results showed that the Ag–Ta thin film deposited for 30 s exhibited higher reflectance in NIR region than those of 5, 10, 20 and 30 s. It demonstrated an average reflectance of about 80% and slightly decreased to 75% after being kept in the air atmosphere for 28 days. It can be likewise proposed as an alternative thin film with high reflectance of NIR radiation single layer to develop industrial low-emission coating for cost-effective, clean, and easy adaptation to a large area coating.

Effect of controlled operating pressure on physical optical and electrical properties of AZO thin film by DC magnetron sputtering technique

The study aimed to research the controlled operating pressure in the range of 1.10 × 10–2 − 2.60 × 10–3 mbar with the adjustment position of plate valve (40 – 100%) using DC pulsed magnetron sputtering system. The AZO films were prepared onto n-type silicon (100) and glass slide substrates. A comparison, all samples were assigned 400 nm of AZO film thickness and then the prepared AZO films were investigated by field-emission scanning electron microscope (FE-SEM) for surface morphologies, X-ray diffraction (XRD) for crystallinity, UV-Vis-NIR spectrophotometry for optical property, Four-point probe and Hall effect instrument for electrical properties, respectively. The results from FE-SEM image showed that the AZO film was columnar structure. The XRD patterns of AZO films demonstrated the crystal growth direction which preferred AZO growth was indicated the (polycrystalline) hexagonal wurtzite structure. For the optical property, the transmittance (%T) clearly showed transparent film, indicating good average value which was 81.54 – 83.28% in visible region (380 to 780 nm of wavelength). Furthermore, the sheet resistivity, high mobility and carrier concentration displayed 91.48 Ohm sq−1, 3.40 cm2 Vs–1 and 7.00 × 1020 cm–3, respectively. These results were decided that the position of plate valve of 85% with operating pressure of 2.70 × 10–3 mbar was the optimal condition. Finally, the excellent electrical and good optical properties of AZO film is mainly applied in several application for optoelectronic device and solar cell.

Design and Manufacturing of Angular DC Magnetron Co- Sputtering System to Provide Multilayer Films

The research aims to design and produced a new vacuum chamber set of the angular multi-target magnetron sputtering system was supplied by three patterns of the process gas emissions in one system. One pattern supplies the gas directly in front of the target surface, while another pattern supplies the gas beside the chamber, and another pattern supplies the gas to the bottom of the lid. The vacuum chamber set was designed as a top-down sputtering process which has six major components is new designed and produced, consists of the base, the chamber with a window, the feedthrough for the anode pole, the lid, the magnetron target-holder gun, and the rotate substrate-holder set. When the system is completely assembled, then try to test the leakage and plasma ignition until both passes tested, and then a preliminary test of the sputtering process to provide a thin fi lm with sputtered one copper target which was mounted on one gun onto glass slide substrates for the gas emissions of three patterns. After that run sputtering process to provide the multilayers fi lms with three target materials include copper, aluminum, and brass, which was mounted on three guns onto the rotate glass slide substrates. The results of the thin fi lm thickness from the sputtering process was found this system can be used to build a thin fi lm for changing various sputtering voltages, including the system can be successfully used to provide multilayers fi lm and generate argon plasma which was supplied three patterns of the process gas emissions in one system.

Real-time monitoring of the pH microenvironment at the interface of multispecies biofilm and dental composites

Bacterial-mediated local pH change plays an important role in altering the integrity of resin dental composite materials in a dynamic environment such as the oral cavity. To address this, we developed a 300-μm-diameter, flexible, solid-state potentiometric pH microsensor capable of detecting and quantifying the local pH microenvironment at the interface of multispecies biofilm and dental resin in real time over 10 days. We used fluorinated poly(3,4-ethylenedioxythiophene) as the back contact in our newly developed pH sensor, along with a PVC-based ion-selective membrane and PTFE-AF coating. The high temporal resolution pH data demonstrated pH changes from 7 to 6 and 7 to 5.8 for the first 2 days and then fluctuated between 6.5 to 6 and 6 to 5.5 for the remaining 8 days with the resin composite or glass slide substrate respectively. We could observe the fluctuations in pH mediated by lactic acid production within the biofilm and the re-establishment of pH back to 7. However, acid production started to overwhelm buffering capacity with the continuous feed of sucrose cycles and reduced the local pH nearer to 5.5. No such changes or fluctuations were observed above the biofilm, as the pH remained at 7.0 ± 0.2 for 10 days. The localized real-time monitoring of the pH within the biofilm showed that the pH shift underneath the biofilm could lead to damage to the underlying material and their interface but cannot be sensed external to the biofilm.

Optical and structural properties of WO3 nanostructure films prepared by oblique angle deposition

Tungsten oxide (WO3) nanostructure thin film has been grown on a silicon wafer and glass slide substrate by reactive magnetron sputtering at a different oblique angle from 56°, 70° and 86°. The effect of static and dynamic substrate tilt rotation during the film deposition on microstructure and the optical property was investigated. The results showed that all of the prepared WO3 nanostructure films were amorphous. The film thickness of the prepared films decreased with increasing deposition angles. Field emission scanning electron microscopy (FE-SEM) revealed that the sample prepared at 70° and 86° with substrate tilt rotation was nanocolumnar structure due to the self-shadowing effect. In addition, the optical transmittance with the omnidirectional property was studied by spectrophotometer. The optical transmittance was about to 86% with a good WO3 nanorod thin films as static OAD at 86°. The energy bandgap can be estimated at about 3.11–3.28 eV.

Dependence of reflectance on angular deposition and film thickness of ZnS/Ag nanolayers

This paper presents the spectral reflectance of thermally evaporated ZnS/Ag nanostructures. The coating of ZnS/Ag nanostructures was performed in two steps while varying the film thickness and deposition angle. Silver metal wire (99.99% purity) was heated under vacuum at a pressure of \(2.5 \times 10^{-5}\) mBars and deposited on glass slide substrates in the diffusion pump microprocessor vacuum coater (Edwards AUTO 306). Pieces of zinc sulphide (99.99% purity) were heated and deposited to the glass slides previously coated with silver to form the ZnS/Ag/glass composite. The optical reflectance of the samples was studied by the UV/Vis/NIR spectrometer (Perkin Elmer Lambda 19) with UV-WinLab software. The reflectance was measured at angles of incidence between \(15^o\) and \(75^o\). Spectrophotometric studies showed that reflectance decreased with decrease in film thickness and decreased with increase in deposition angle of silver nanoparticles. The reflectance of ZnS/Ag nanostructures decreased with increase in deposition angle of zinc sulphide.

Transparent thermoelectric properties of copper iodide thin films

Copper Iodide (CuI) transparent thin films were synthesized by using the as-deposited Cu thin film dip in the Iodine (I2) solution (1% per 100 cc.) for 15s, 30s, and 60s within the liquid iodination method. The as-deposited Cu thin films on glass slide substrates as used were prepared by a dc magnetron sputtering method from the Cu target. The microstructure, morphology, and thermoelectric properties were studied by using X-ray diffraction (XRD) techniques, scanning electron microscopy (SEM), and the ZEM-3 method, respectively. The optical property of the film samples was determined from measured transmittance using a UV–visible spectrophotometer. The optical bandgap energy is 3.0 eV and the transmittance is around 80–95% for the thin film as dipped 30s. At room temperature, the power factor of Cul thin films were 14.71, 17.49, and 17.48 μW m−1 K−2 for as dipped 15s, 30s, and 60s, respectively.

Sputter-grown Eu-doped WO3-Eu2(WO4)3 composite red phosphor thin films

Eu3+-activated WO3-Eu2(WO4)3 luminescent composite thin films are grown on low-cost slide glass substrates by radio frequency sputtering and then annealing in an air atmosphere furnace. The films obtained by sputtering 12 at.% of Eu-added WO3 target afforded a two-phase composite structure comprising Eu-doped WO3 and Eu2(WO4)3 after annealing. The composite thin films annealed at 600 °C exhibited strong red emission after growing at room temperature compared to those annealed at 500 °C under the excitation of 254, 394, and 465 nm corresponding to ultraviolet, near-ultraviolet, and blue light, respectively. The thin films grown at low temperatures without annealing did not emit under ultraviolet light. The crystalline structure, surface morphology, and optical properties, such as transmittance and photoluminescence, of the films grown at 500 °C were almost similar to those of the thin films grown at room temperature when they were annealed at the same temperature. Pure WO3 thin films without Eu doping showed similar crystallization behavior under the same annealing conditions as Eu-added composite films; however, they did not exhibit photoluminescence properties. Our report on the integration of thin-film red phosphors on glass substrates is promising for the development of low-cost and large-area optical devices activated at various excitation wavelengths.

SURFACE-ENHANCED RAMAN SCATTERING ACTIVITY OF PLASMONIC Ag–Ti NANOISLAND FILMS

Bimetallic nanostructure of noble metals is an alternative material that can provide the tenability of plasmonic performance. In this study, the plasmonic silver–titanium nanoisland (Ag–Ti NI) films deposited on a silicon wafer and glass slide substrates were prepared by magnetron co-sputtering of high-purity Ag target (99.99%) operated at 100 W-DC source, and Ti target (99.99%) operated at 50–250 W-DC pulsed source. The surface morphologies of the prepared films revealed a noncontinuous island Ag–Ti according to the formation of thin film growth based on the Volmer–Weber model. An increase in the sputtering power of the Ti target caused an evident increase in the Ag–Ti NIs diameter. The localized surface plasmon resonance (LSPR) was evaluated by UV–Vis–NIR spectrophotometry. The LSPR peak shift disappears with an increase of the sputtering power of the Ti target.In addition, the results confirmed that the surface-enhanced Raman scattering (SERS) activity of the bimetallic Ag–Ti NIs significantly improved in performance and stability, which is promising for the application in analytical chemistry.

Experimental and theoretical study of the characteristics of LSPR peaks for metal NPs produced by controlling Ar ambient gas pressure to enhance the efficiency of solar cells

In this study, silver (Ag) nanoparticle thin films were deposited on microscope slide glass and Si wafer substrates using the pulsed-laser deposition (PLD) technique in Ar ambient gas pressures of 1 × 10−3 and 7.5 × 10−1 mbar. AFM analysis has shown that the number of Ag nanoparticles reaching the substrate decreased with increasing Ar gas pressure. As a result of Ar ambient gas being allowed into the vacuum chamber, it was observed that the size and height of Ag nanoparticles decreased and the interparticle distances decreased. According to the absorption spectra taken by a UV–vis spectrometer, the wavelength where the localised surface plasmon resonance (LSPR) peak appeared was shifted towards the longer wavelength region in the solar spectrum as Ar background gas pressure was decreased. This experiment shows that LSPR wavelength can be tuned by adjusting the size of metal nanoparticles, which can be controlled by changing Ar gas pressure. The obtained extinction cross section spectra for Ag nanoparticle thin film was theoretically analysed and determined by using the metal nanoparticle–boundary element method (MNPBEM) toolbox simulation program. In this study, experimental spectrum and simulation data for metal nanoparticles were acquired, compared, and determined to be in agreement.

Study of optical properties of ZnS and MnZnS (ZnS/MnS) nanostructure thin films; Prepared by microwave-assisted chemical bath deposition method

The main objective of this work is the preparation of ZnS and MnZnS (ZnS/MnS) nanostructure thin films in an ammonia-free solution by microwave-assisted chemical bath deposition (MA-CBD) method and decreasing consume of energy via decreasing deposition time from several hours to several minutes compared to conventional CBD method. ZnS and MnZnS films were deposited on commercial microscope slide glass substrates using acetic acid as a safe complexing agent. Growth rate of the film thickness was obtained approximately 1.8–2.0 nm/min. The influence of [S2−/Zn2+] molar ratio on the formation, quality, and optical properties of the films was investigated. X-ray diffraction results approved the formation of MnS/ZnS hybrid films with a cubic structure for the ZnS and MnS. Atomic force microscopy (AFM) measured the average of roughness around 6.4 nm. Field emission scanning electron microscopy (FE-SEM) exhibited that the layers were dense, homogenous, and free of pinhole or crack with very small particles at about 10–40 nm. Energy-dispersive X-ray spectrometer (EDX) revealed the presence of the Mn in the ZnS thin film and confirmed the deficiency of sulfide in the films. Fluorescence (FL) emission spectra of the films showed a strong dependence on composition as well as population (density) of defect states such as S vacancies. UV–vis results indicated that all films are highly transparent, and their band gap energy varies from 3.6eV to 3.85eV.