Distributed phase shifters using (Ba,Sr)TiO3 thin films on sapphire and glass substrates

CdS thin films were deposited on glass substrates by using successive ionic layer adsorption and reaction (SILAR) method at room temperature. The effect of SILAR growth cycles on structural, morphological, optical and electrical properties of the films has been studied.Â The thickness of the deposited film is measured by employing weight difference method. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) studies showed that all the films exhibit polycrystalline nature and are covered well with glass substrates. The values of average crystallite size were found to be 53 nm, 58 nm, 63 nm and 71 nm corresponding to the thin films deposited with 30, 40, 50 and 60 SILAR growth cycles respectively. From the UVâ€“VIS spectra of the deposited thin films, it was seen that both the absorption properties and energy bandgap of the films changes with increasing number of SILAR growth cycles. A decrease of electrical resistivity has been observed with increasing SILAR growth cycle.Â

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PREPARATION AND CHARACTERIZATION OF POLYVINYL ALCOHOL THIN FILMS FOR ORGANIC THIN FILM TRANSISTORS AND BIOMEDICAL APPLICATIONS

Kongunadu Research Journal ◽

10.26524/krj264 ◽

2018 ◽

Vol 5 (2) ◽

pp. 16-18

Author(s):

Chandar Shekar B ◽

Ranjit Kumar R ◽

Dinesh K.P.B ◽

Sulana Sundar C ◽

Sunnitha S ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Thin Film Transistors ◽

Gravimetric Method ◽

Dip Coating ◽

Organic Thin Film Transistors ◽

Poly Vinyl Alcohol ◽

Organic Thin Film ◽

Glass Substrates ◽

Coating Method

Thin films of poly vinyl alcohol (PVA) were prepared on pre-cleaned glass substrates by Dip Coating Method. FTIR spectrum was used to identify the functional groups present in the prepared films. The vibrational peaks observed at 1260 cm-1 and 851 cm-1 are assigned to C–C stretching and CH rocking of PVA.The characteristic band appearing at 1432 cm-1 is assigned to C–H bend of CH2 of PVA. The thickness of the prepared thin films were measured by using an electronic thickness measuring instrument (Tesatronic-TTD20) and cross checked by gravimetric method. XRD spectra indicated the amorphous nature of the films.Surface morphology of the coated films was studied by scanning electron microscope (SEM). The surface revealed no pits and pin holes on the surface. The observed surface morphology indicated that these films could be used as dielectric layer in organic thin film transistors and as drug delivery system for wound healing.

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X- ray diffraction and dielectric properties of PbSe thin films

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v15i34.115 ◽

2019 ◽

Vol 15 (34) ◽

pp. 1-14

Author(s):

Bushra A. Hasan

Keyword(s):

Thin Films ◽

Thermal Activation ◽

Thermal Evaporation ◽

Thermal Activation Energy ◽

Dielectric Constants ◽

Conductivity Measurements ◽

X Ray Diffraction ◽

Thermal Evaporation Method ◽

X Ray ◽

Glass Substrates

Lead selenide PbSe thin films of different thicknesses (300, 500, and 700 nm) were deposited under vacuum using thermal evaporation method on glass substrates. X-ray diffraction measurements showed that increasing of thickness lead to well crystallize the prepared samples, such that the crystallite size increases while the dislocation density decreases with thickness increasing. A.C conductivity, dielectric constants, and loss tangent are studied as function to thickness, frequency (10kHz-10MHz) and temperatures (293K-493K). The conductivity measurements confirm confirmed that hopping is the mechanism responsible for the conduction process. Increasing of thickness decreases the thermal activation energy estimated from Arhinus equation is found to decrease with thickness increasing. The increase of thickness lead to reduce the polarizability α while the increasing of temperature lead to increase α.

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Sol-gel growth of Ni doped CdS on glass substrates: effect of spin coating speed and dopant concentration

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681210999200423120817 ◽

2020 ◽

Vol 10 ◽

Author(s):

Atefeh Nazari Setayesh ◽

Hassan Sedghi

Keyword(s):

Thin Films ◽

Optical Properties ◽

Spin Coating ◽

Optical Band Gap ◽

Dopant Concentration ◽

Rotation Speed ◽

Sol Gel ◽

Band Gap Energy ◽

Gap Energy ◽

Glass Substrates

Background: In this work, CdS thin films were synthesized by sol-gel method (spin coating technique) on glass substrates to investigate the optical behavior of the film. Methods: Different substrate spin coating speeds of 2400, 3000, 3600 rpm and different Ni dopant concentrations of 0 wt.%, 2.5 wt.%, 5 wt.%) were investigated. The optical properties of thin films such as refraction index, extinction coefficient, dielectric constant and optical band gap energy of the layers were discussed using spectroscopic ellipsometry method in the wavelength range of 300 to 900 nm. Results: It can be deduced that substrate rotation speed and dopant concentration has influenced the optical properties of thin films. By decreasing rotation speed of the substrate which results in films with more thicknesses, more optical interferences were appeared in the results. Conclusion: The samples doped with Ni comparing to pure ones have had more optical band gap energy.

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Deposition time dependent study of structural and optical properties of PbS thin films grown by CBD method

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) ◽

10.2174/2405520413999200517123919 ◽

2020 ◽

Vol 13 ◽

Author(s):

Minakshi Chaudhary ◽

Yogesh Hase ◽

Ashwini Punde ◽

Pratibha Shinde ◽

Ashish Waghmare ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Band Gap ◽

Deposition Time ◽

Secondary Growth ◽

Cost Effective ◽

Xrd Analysis ◽

Structural Morphology ◽

Glass Substrates ◽

Cbd Method

: Thin films of PbS were prepared onto glass substrates by using a simple and cost effective CBD method. Influence of deposition time on structural, morphology and optical properties have been investigated systematically. The XRD analysis revealed that PbS films are polycrystalline with preferred orientation in (200) direction. Enhancement in crystallinity and PbS crystallite size has been observed with increase in deposition time. Formation of single phase PbS thin films has been further confirmed by Raman spectroscopy. The surface morphology analysis revealed the formation of prismatic and pebble-like PbS particles and with increase in deposition time these PbS particles are separated from each other without secondary growth. The data obtained from the EDX spectra shows the formation of high-quality but slightly sulfur rich PbS thin films over the entire range of deposition time studied. All films show increase in absorption with increase in deposition time and a strong absorption in the visible and sub-band gap regime of NIR range of the spectrum with red shift in band edge. The optical band gap shows decreasing trend, as deposition time increases but it is higher than the band gap of bulk PbS.

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Out-of-Plane Thermal Expansion Coefficient and Biaxial Young’s Modulus of Sputtered ITO Thin Films

Coatings ◽

10.3390/coatings11020153 ◽

2021 ◽

Vol 11 (2) ◽

pp. 153

Author(s):

Chuen-Lin Tien ◽

Tsai-Wei Lin

Keyword(s):

Thin Films ◽

Thermal Expansion ◽

Thermal Stress ◽

Young’S Modulus ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Young's Modulus ◽

Heating Temperature ◽

Glass Substrates ◽

Ito Thin Films

This paper proposes a measuring apparatus and method for simultaneous determination of the thermal expansion coefficient and biaxial Young’s modulus of indium tin oxide (ITO) thin films. ITO thin films simultaneously coated on N-BK7 and S-TIM35 glass substrates were prepared by direct current (DC) magnetron sputtering deposition. The thermo-mechanical parameters of ITO thin films were investigated experimentally. Thermal stress in sputtered ITO films was evaluated by an improved Twyman–Green interferometer associated with wavelet transform at different temperatures. When the heating temperature increased from 30 °C to 100 °C, the tensile thermal stress of ITO thin films increased. The increase in substrate temperature led to the decrease of total residual stress deposited on two glass substrates. A linear relationship between the thermal stress and substrate heating temperature was found. The thermal expansion coefficient and biaxial Young’s modulus of the films were measured by the double substrate method. The results show that the out of plane thermal expansion coefficient and biaxial Young’s modulus of the ITO film were 5.81 × 10−6 °C−1 and 475 GPa.

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Galvanostatically deposited Co3O4–NiO nanocomposite thin films onto FTO glass substrates: An investigation of their microstructural and supercapacitive properties

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.159022 ◽

2021 ◽

Vol 867 ◽

pp. 159022

Author(s):

P.P. Sahay

Keyword(s):

Thin Films ◽

Glass Substrates ◽

Nanocomposite Thin Films ◽

Fto Glass

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Solid Phase Growth of some Metal and Metal Oxide Thin Films on Sapphire and Quartz Glass Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.753.505 ◽

2013 ◽

Vol 753 ◽

pp. 505-509

Author(s):

Yuichi Sato ◽

Toshifumi Suzuki ◽

Hiroyuki Mogami ◽

Fumito Otake ◽

Hirotoshi Hatori ◽

...

Keyword(s):

Thin Films ◽

Quartz Glass ◽

Glass Substrate ◽

Solid Phase ◽

Quartz Glass Substrate ◽

Heteroepitaxial Growth ◽

Phase Growth ◽

Single Crystalline ◽

Glass Substrates ◽

Amorphous Quartz

Solid phase growth of thin films of copper (Cu), aluminum (Al) and zinc oxide (ZnO) on single crystalline sapphire and quartz glass substrates were tried by heat-treatments and their crystallization conditions were investigated. ZnO thin films relatively easily recrystallized even when they were deposited on the amorphous quartz glass substrate. On the other hand, Cu and Al thin films hardly recrystallized when they were deposited on the quartz glass substrate. The metal thin films could be recrystallized at only extremely narrow windows of the heat-treatment conditions when they were deposited on the single crystalline sapphire substrate. The window of the solid phase heteroepitaxial growth condition of the Al film was wider than that of the Cu film.

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Tuning the Electrical Properties of NiO Thin Films by Stoichiometry and Microstructure

Coatings ◽

10.3390/coatings11060697 ◽

2021 ◽

Vol 11 (6) ◽

pp. 697

Author(s):

Yu-He Liu ◽

Xiao-Yan Liu ◽

Hui Sun ◽

Bo Dai ◽

Peng Zhang ◽

...

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Energy Loss ◽

Single Crystal ◽

Oxygen Stoichiometry ◽

High Resistivity ◽

Edge Structure ◽

Glass Substrates ◽

Lower Resistivity

Here, the electrical properties of NiO thin films grown on glass and Al2O3 (0001) substrates have been investigated. It was found that the resistivity of NiO thin films strongly depends on oxygen stoichiometry. Nearly perfect stoichiometry yields extremely high resistivity. In contrast, off-stoichiometric thin films possess much lower resistivity, especially for oxygen-rich composition. A side-by-side comparison of energy loss near the edge structure spectra of Ni L3 edges between our NiO thin films and other theoretical spectra rules out the existence of Ni3+ in NiO thin films, which contradicts the traditional hypothesis. In addition, epitaxial NiO thin films grown on Al2O3 (0001) single crystal substrates exhibit much higher resistivity than those on glass substrates, even if they are deposited simultaneously. This feature indicates the microstructure dependence of electrical properties.

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