Investigation on Sensing and Stability of Nitrogen-doped ITO Thin-film Strain Gauges at High Temperatures

Abstract Nitrogen-doped indium tin oxide (ITO) has been applied in the thin-film strain gauges (TFSGs) due to their high stability, excellent piezoresistivity and antioxidation at elevated temperatures. However, the mechanism on the sensing and stability of the nitrogen-doped ITO TFSGs at high temperatures was not comprehensively clarified. In this work, various ITO TFSGs were fabricated by RF magnetron sputtering with different nitrogen partial pressures (NPPs) of 5%~40%. The elemental composition and band structures of the ITO TFSGs were examined by the energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), respectively. Results show that the Fermi energy level shifts closer to the valence band maximum energy (Ev) gradually with the growth of NPPs, causing a reduction in the number of electrons ionized to the conduction band. The smallest content change rates of nitrogen (3.8%) and oxygen (1.6%) after subjecting to the thermal strain test were observed in the 20%N2 ITO TFSG. In consequence, the 20%N2 ITO TFSG exhibits the lowest resistance drift rate (DR) at high temperatures due to its stable elemental composition. Moreover, we found that the band structures and elemental composition of the ITO TFSGs are the main factors affecting their piezoresistive response at different temperatures. The band structures play a major role in the gauge factors (GFs) of the ITO TFSGs at room temperature and 600 ℃. The element variation takes responsibility for the different GFs of the ITO TFSGs at 800℃, 900℃ and 1000℃. In addition, the piezoresistive stability is also dependent on the elemental composition affected by the dynamic equilibrium between the diffusion amount of oxygen and the escape number of the nitrogen in the ITO thin films at high temperatures.

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Effect of V and Ti on the Oxidation Resistance of WMoTaNb Refractory High-Entropy Alloy at High Temperatures

Metals ◽

10.3390/met12010041 ◽

2021 ◽

Vol 12 (1) ◽

pp. 41

Author(s):

Shuaidan Lu ◽

Xiaoxiao Li ◽

Xiaoyu Liang ◽

Wei Yang ◽

Jian Chen

Keyword(s):

Oxidation Resistance ◽

High Temperatures ◽

Elevated Temperatures ◽

Early Stage ◽

Mass Gain ◽

High Entropy Alloy ◽

High Entropy Alloys ◽

X Ray Diffraction ◽

X Ray ◽

High Entropy

Alloying with V and Ti elements effectively improves the strength of WMoTaNb refractory high entropy alloys (RHEAs) at elevated temperatures. However, their effects on the oxidation resistance of WMoTaNb RHEAs are unknown, which is vitally important to their application at high temperatures. In this work, the effect of V and Ti on the oxidation behavior of WMoTaNb RHEA at 1000 °C was investigated using a thermogravimetric system, X-ray diffraction and scanning electron microscopy. The oxidation of all alloys was found to obey a power law passivating oxidation at the early stage. The addition of V aggravates the volatility of V2O5, MoO3 and WO3, and leads to disastrous internal oxidation. The addition of Ti reduces the mass gain in forming the full coverage of passivating scale and prolongs the passivation duration of alloys.

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Growth of Copper Indium Telluride (Cuinte2) Thin Films Using Electrochemical Route for Photovoltaic Application

Nepal Journal of Science and Technology ◽

10.3126/njst.v12i0.6519 ◽

2012 ◽

Vol 12 ◽

pp. 318-323 ◽

Cited By ~ 1

Author(s):

Subash Adhikari ◽

NB Chaure

Keyword(s):

Thin Films ◽

Band Gap ◽

Elemental Composition ◽

Indium Tin Oxide ◽

Secondary Phase ◽

Annealed Sample ◽

X Ray ◽

Copper Indium ◽

Electrochemically Deposited ◽

Indium Telluride

Copper indium di-telluride (CuInTe2; CIT) was electrochemically deposited onto indium tin oxide (ITO) substrate using aqueous medium at various electrodeposition conditions like temperature, pH, stirring rate and concentration of the samples. The resulting thin films were characterized using UV-Visible-NIR spectrophotometer, X-ray diffractometer, scanning electron microscopy and energy dispersive X-ray to find out energy band gap, structural properties, surface morphology and the elemental composition in the film respectively. The resulting films showed a polycrystalline nature with band gap varying from 1.27 to 1.89 eV. The elemental composition of the as deposited and annealed sample showed that the films were mostly copper and tellurium rich. The crystallinity of the films improved after annealing for 5 minutes at 350°C but the secondary phase like CuxTe and InxTe could not be recombined completely.DOI: http://dx.doi.org/10.3126/njst.v12i0.6519 Nepal Journal of Science and Technology 12 (2011) 318-323

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pH sensor based on Au NPs/ ITO membrane as extended gate field-effect transistor

10.21203/rs.3.rs-593380/v1 ◽

2021 ◽

Author(s):

Saleh K. Alsaee ◽

Naser Mahmoud Ahmed ◽

Elham Mzwd ◽

Ahmad Fairuz Omar ◽

A.I. Aljameel ◽

...

Keyword(s):

Thin Film ◽

Electron Microscope ◽

Indium Tin Oxide ◽

Field Effect ◽

Field Effect Transistor ◽

Spectroscopic Techniques ◽

Au Nps ◽

X Ray ◽

Vis Spectroscopy ◽

Effect Transistor

Abstract In the present work, gold nanoparticles (Au NPs) were synthesized on indium tin oxide (ITO) thin film on glass substrate for the pH sensing application based on extended gate field effect transistor (EGFET). The ITO thin film was deposited on glass using RF sputtering and then the Au NPs were synthesized on it by pulsed laser ablation in liquid (PLAL) technique. The Au NPs were characterized using transmission electron microscope (TEM), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopic techniques. From the TEM analysis, the size of the spherical shaped Au NPs was found to be in the range of 5–22 nm. The UV-Vis spectroscopy analysis revealed absorption peak at 518 nm, indicating purplish red color. The XPS data revealed Au 4f doublet binding energy peaks of the photoelectrons at 83.79 and 87.45 eV. The current-voltage (I-V) curves indicated pH sensitivities values of 43.6 mV/pH and 0.6 \({\left(\mu A\right)}^{\frac{1}{2}} /pH\) with linear regression of 0.9. The hysteresis and drift characteristics of Au NPs/ITO/G membrane were also studied to investigate its stability and reliability. The results of this work demonstrated that the Au NPs/ITO/G membrane is quite useful for the acidity and basicity detection.

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Electrodeposition of lithium phthalocyanine thin films: Part I. Structure and morphology

Journal of Materials Research ◽

10.1557/jmr.1999.0292 ◽

1999 ◽

Vol 14 (5) ◽

pp. 2162-2172 ◽

Cited By ~ 8

Author(s):

M. Brinkmann ◽

S. Graff ◽

C. Chaumont ◽

J-J. André

Keyword(s):

Thin Film ◽

Thin Films ◽

Indium Tin Oxide ◽

Film Growth ◽

Oxidation Potential ◽

Thin Film Growth ◽

Ex Situ ◽

X Ray Diffraction ◽

X Ray ◽

Film Synthesis

A new thin film synthesis route based on the electrochemical oxidation of PcLi2 and deposition of lithium phthalocyanine (PcLi) onto indium tin oxide (ITO) substrate is demonstrated. The effects on the thin film morphology of various parameters such as the electrolysis time, the nature of the solvent, and the oxidation potential are investigated. The thin film growth is studied via x-ray diffraction, potential step experiments, and ex situ scanning electron microscopy. Various morphologies of the x-form thin films are observed for different electrolysis times and solvents. Thin films grown in acetonitrile of thickness above 1 μm consist in unidirectionally oriented needle-shaped crystallites.

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Self-ordering of silicon polymer thin film grown on indium tin oxide surface investigated by X-ray absorption spectroscopy

Journal of Electron Spectroscopy and Related Phenomena ◽

10.1016/j.elspec.2010.02.014 ◽

2010 ◽

Vol 181 (2-3) ◽

pp. 242-248 ◽

Cited By ~ 5

Author(s):

Md. Abdul Mannan ◽

Yuji Baba ◽

Tetsuhiro Sekiguchi ◽

Iwao Shimoyama ◽

Norie Hirao ◽

...

Keyword(s):

Thin Film ◽

Absorption Spectroscopy ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Oxide Surface ◽

Polymer Thin Film ◽

X Ray ◽

X Ray Absorption

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INFLUENCE OF THE SUBSTRATE ON THE CRYSTALLINE PHASE AND MORPHOLOGY OF POLY (VINYLIDENE FLUORIDE) (PVDF) THIN FILM

Surface Review and Letters ◽

10.1142/s0218625x16500050 ◽

2016 ◽

Vol 23 (03) ◽

pp. 1650005 ◽

Cited By ~ 2

Author(s):

IBTISAM YAHYA ABDULLAH ◽

MUHAMMAD YAHAYA ◽

MOHAMMAD HAFIZUDDIN HJ JUMALI ◽

HAIDER MOHAMMED SHANSHOOL

Keyword(s):

Thin Film ◽

Indium Tin Oxide ◽

Crystalline Phase ◽

Vinylidene Fluoride ◽

Average Diameter ◽

X Ray Diffraction ◽

X Ray ◽

Coated Glass ◽

Poly Vinylidene Fluoride ◽

Hexamethyl Phosphoramide

The effect of substrate on the crystalline phase and morphology of the poly (vinylidene fluoride) (PVDF) thin film has been investigated. The solution of PVDF/Hexamethyl phosphoramide (HMPA) was deposited on four different substrates, namely, silicon (Si), glass (SiO2), indium tin oxide (ITO) coated glass and silver (Ag) coated glass respectively by using the spin coating technique. The crystalline structure was investigated using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques. The morphology was determined using scanning electron microscopy (SEM). XRD demonstrated that the structure of PVDF thin films on each substrate is [Formula: see text]-phase with different orientations of the molecular chains. FTIR results confirmed XRD that the samples contain [Formula: see text]-phase. SEM shows spherulites structure, which is rough and porous, besides, the size of spherulites and the porosity are different for each sample. The size of spherulites is in average diameter range (1–6[Formula: see text][Formula: see text]m) and this range is attributed to the [Formula: see text]-phase. The nucleation process of [Formula: see text]-phase on the various substrates attributed either to the match of polymer-substrate or to the electrostatic interaction. Among the substrates used, the ITO substrate exhibited a greater tendency for [Formula: see text]-phase formation.

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Effect of Oxygen Partial Pressure on the Phase Stability of Copper–Iron Delafossites at Elevated Temperatures

Materials ◽

10.3390/ma11101888 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1888 ◽

Cited By ~ 3

Author(s):

Thomas Stöcker ◽

Ralf Moos

Keyword(s):

Oxygen Partial Pressure ◽

Partial Pressure ◽

High Temperatures ◽

Phase Stability ◽

Elevated Temperatures ◽

Process Window ◽

Thermoelectric Generators ◽

X Ray Diffraction ◽

Characterization Methods ◽

X Ray

Oxide-based materials are promising candidates for use in high temperature thermoelectric generators. While their thermoelectric performance is inferior to commonly used thermoelectrics, oxides are environmentally friendly and cost-effective. In this study, Cu-based delafossites (CuFeO2), a material class with promising thermoelectric properties at high temperatures, were investigated. This work focuses on the phase stability of CuFeO2 with respect to the temperature and the oxygen partial pressure. For this reason, classical material characterization methods, such as scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction, were combined in order to elucidate the phase composition of delafossites at 900 °C at various oxygen partial pressures. The experimentally obtained results are supported by the theoretical calculation of the Ellingham diagram of the copper–oxygen system. In addition, hot-stage X-ray diffraction and long-term annealing tests of CuFeO2 were performed in order to obtain a holistic review of the phase stability of delafossites at high temperatures and varying oxygen partial pressure. The results support the thermoelectric measurements in previous publications and provide a process window for the use of CuFeO2 in thermoelectric generators.

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