scholarly journals DEVELOPMENT AND EXPERIMENTAL STUDIES OF METHODS FOR INCREASING THE STABILITY OF MATERIALS OF ACCELERATING STRUCTURES TO HIGH VACUUM ELECTRICAL DISCHARGES

2019 ◽  
pp. 23-26
Author(s):  
V.A. Baturin ◽  
A.Yu. Karpenko ◽  
S.A. Yeryomin

The experimental technique is described and the results of a study of the resistance to high vacuum electrical breakdowns of copper samples coated with thin films of titanium nitride are presented. The studies were carried out in a two-electrode system having the so-called “plane-tip” configuration. Using the method of X-ray diffractometry, we studied the effect of the structure of titanium nitride films on their efficiency as a material that reduces the probability of breakdown.

1989 ◽  
Vol 50 (C7) ◽  
pp. C7-169-C7-173
Author(s):  
R.C BUSCHERT ◽  
P. N. GIBSON ◽  
W. GISSLER ◽  
J. HAUPT ◽  
T. A. CRABB
Keyword(s):  

1992 ◽  
Vol 270 ◽  
Author(s):  
Haojie Yuan ◽  
R. Stanley Williams

ABSTRACTThin films of pure germanium-carbon alloys (GexC1−x with x ≈ 0.0, 0.2, 0.4, 0.5, 0.6, 0.8, 1.0) have been grown on Si(100) and A12O3 (0001) substrates by pulsed laser ablation in a high vacuum chamber. The films were analyzed by x-ray θ-2θ diffraction (XRD), x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), conductivity measurements and optical absorption spectroscopy. The analyses of these new materials showed that films of all compositions were amorphous, free of contamination and uniform in composition. By changing the film composition, the optical band gap of these semiconducting films was varied from 0.00eV to 0.85eV for x = 0.0 to 1.0 respectively. According to the AES results, the carbon atoms in the Ge-C alloy thin film samples has a bonding configuration that is a mixture of sp2 and sp3 hybridizations.


2021 ◽  
Vol 12 (1) ◽  
pp. 1
Author(s):  
Julia Marí-Guaita ◽  
Amal Bouich ◽  
Bernabé Marí

In this work, FAPbI3 thin films with different antisolvents (toluene, diethyl ether and chlorobenzene) were successfully elaborated by the spin coating technique to study the influence of the different antisolvents in the films. The crystal structure, surface morphology and optical properties were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) photoluminescence and UV–visible spectrometry. According to XRD, the crystalline structure of FAPbI3 was found in the orientation of the (110) plane, and it is observed that the type of antisolvent content in the absorber layer plays an important role in the growth and stabilization of the film. Here, chlorobenzene leads to a smooth and homogenous surface, a large grain size and a pinhole-free perovskite film. Additionally, the optical analysis revealed that the band gap is in the range from 1.55 to 1.57 eV. Furthermore, in an approximately 60% humidity environment and after two weeks, the stability and absorption of FaPbI3 showed low degradation.


2015 ◽  
Vol 1131 ◽  
pp. 35-38
Author(s):  
Navaphun Kayunkid ◽  
Annop Chanhom ◽  
Chaloempol Saributr ◽  
Adirek Rangkasikorn ◽  
Jiti Nukeaw

This research is related to growth and characterizations of indium-doped pentacene thin films as a novel hybrid material. Doped films were prepared by thermal co-evaporation under high vacuum. The doping concentration was varied from 0% to 50% by controlling the different deposition rate between these two materials while the total thickness was fixed at 100 nm. The hybrid thin films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD) and UV-Visible spectroscopy to reveal the physical and optical properties. Moreover, the electrical properties of ITO/indium-doped-pentacene/Al devices i.e. charge mobility and carrier concentration were determined by considering the relationship between current-voltage and capacitance-voltage. AFM results identify that doping of indium into pentacene has an effect on surface properties of doped films i.e. the increase of surface grain size. XRD results indicate that doping of metal into pentacene has an effect on preferential orientation of pentacene’s crystalline domains. UV-Vis spectroscopy results show evolution of absorbance at photon energy higher than 2.7 eV corresponding to absorption from oxide of indium formed in the films. Electrical measurements exhibit higher conductivity in doped films resulting from increment of both charge carrier mobility and carrier concentration. Furthermore, chemical interactions taken place inside the doped films were investigated by x-ray photoelectron spectroscopy (XPS) in order to complete the remaining questions i.e. how do indium atoms interact with the neighbor molecules?, what is the origin of the absorption at E > 2.7 eV? Further results and discussions will be presented in the publication.


1992 ◽  
Vol 242 ◽  
Author(s):  
W. J. Meng ◽  
T. A. Perry ◽  
J. Heremans ◽  
Y. T. Cheng

ABSTRACTThin films of aluminum nitride were grown epitaxially on Si(111) by ultra-high-vacuum dc magnetron reactive sputter deposition. Epitaxy was achieved at substrate temperatures of 600° C or above. We report results of film characterization by x-ray diffraction, transmission electron microscopy, and Raman scattering.


1987 ◽  
Vol 01 (02) ◽  
pp. 571-574
Author(s):  
Jia-qi Zheng ◽  
Guo-guang Zheng ◽  
Dong-qi Li ◽  
Wei Wang ◽  
Jin-min Xue ◽  
...  

Y-Ba-Cu-O thin films are deposited onto severval kinds of substrates by electron beam evaporating in a high vacuum system. After the heat treatment at 850–890°c for 1hr the Y-Ba-Cu-O films on the BaF2 substrates show superconducting behaviors with the midpoint Tc around 87K and zero resistance temperature at 77K. The composition and stucture analysis of these films have been studied by AES, XRFS and x-ray diffraction.


Coatings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 87
Author(s):  
Atef S. Gadalla ◽  
Hamdan A. S. Al-shamiri ◽  
Saad Melhi Alshahrani ◽  
Huda F. Khalil ◽  
Mahmoud M. El Nahas ◽  
...  

In this study, cadmium Sulfide (CdS) thin films were synthesized on quartz substrates using an infrared pulsed laser deposition (IR-PLD) technique under high vacuum (~10−6 Torr) conditions. X-ray diffraction was used to evaluate the structural features. According to X-ray analysis, the deposited CdS films are crystalline and have a favored orientation on a plane (110) of an orthorhombic. The peak intensity and the average crystallite size increases with increasing the film thickness. After annealing at 300 °C, the orthorhombic phase transformed into a predominant hexagonal phase and the same result was obtained by SEM photographs as well. Spectrophotometric measurements of transmittance and reflectance of the CdS films were used to derive optical constants (n, k, and absorption coefficient α). The optical band gap energy was found to be 2.44 eV. The plasma plume formation and expansion during the film deposition have also been discussed. The photocurrent response as a function of the incident photon energy E (eV) at different bias voltages for different samples of thicknesses (85, 180, 220 and 340 nm) have been studied, indicating that the photocurrent increases by increasing both the film thickness and photon energy with a peak in the vicinity of the band edge. Thus, the prepared CdS films are promising for application in optoelectronic field.


Author(s):  
Manosi Roy ◽  
Dhananjay Kumar

Abstract The objective of this study is to investigate the effect of film thickness on the bandgap of oxygen (O2)-doped titanium nitride (TiN) thin films. To accomplish this, high-quality two-dimensional O2-doped TiN films have been prepared on single-crystal sapphire substrates using a pulsed laser deposition method. The film thicknesses were varied from 3 to 100 nm by varying the number of laser pulses, while other deposition parameters are kept constant. X-ray diffraction (XRD) patterns have shown that the films grow in (111) orientation on the sapphire substrate. The increase in the intensity of the XRD (111) peak also demonstrates a better orientational alignment of the TiN films with substrate as the film thickness increases. The x-ray rocking curve has been used to measure the full width half maxima (FWHM) for each film. The FWHM values has been found to vary from 0.07 to 0.2° as the film thickness decreases. This is taken to indicate that the grain size decreases with a decrease in film thickness. Ultraviolet visible spectroscopy measurements in the wavelength range (200–800 nm) have been performed as well, which indicates an increase in the bandgap of O2-doped TiN films with a decrease in film thickness. The decrease in the film thickness leads to a blue shift of the peak in the ultraviolet-visible absorption (UV-A) region; this blueshift is accompanied by an increase in the bandgap of O2-doped TiN from 3.2 to 3.8 eV. The change in the bandgap due to a change in film thickness has been explained using the quantum confinement effect.


2008 ◽  
Vol 595-598 ◽  
pp. 797-804 ◽  
Author(s):  
Cezarina C. Mardare ◽  
Michael Spiegel ◽  
Alan Savan ◽  
Alfred Ludwig

Ternary Mn-Co-Fe metallic thin films were deposited by RF-magnetron co-sputtering on SiO2/Si wafers and on ZMG232L (Hitachi Metals®), a special ferritic stainless steel for Solid Oxide Fuel Cell applications. The deposition was followed by heat treatment in an oxidizing atmosphere in order to convert the metallic thin films to (Mn,Co,Fe)3O4 spinel oxides. Coated and uncoated steel samples were analyzed after 1 h heat treatment in order to confirm the presence of the spinel structure on top of the steel, as well as to investigate and characterize the growth of oxides, namely (Mn,Cr)3O4 and Cr2O3, at the internal steel/coating interface. From Grazing Incidence X-ray Diffraction (GI-XRD) investigations together with Energy Dispersive X-ray analysis – Scanning Electron Microscopy and Time of Flight – Secondary Ions Mass Spectroscopy sputtering depth profiling the presence of well adherent (Mn,Co,Fe)3O4 coatings with approximately 500 nm thickness and a grain size of about 150 nm was confirmed. After the preparation annealing, some samples were heat-treated in simulated cathodic atmospheres at 800 °C for 500 h in order to assess the stability of the coatings. GI-XRD spectra still showed the presence of the protective coatings, however sputtering depth profile analysis indicated the presence of Cr on the surface.


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