scholarly journals PECVD SiNx Thin Films for Protecting Highly Reflective Silver Mirrors: Are They Better Than ALD AlOx Films?

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 771
Author(s):  
Pavel Bulkin ◽  
Patrick Chapon ◽  
Dmitri Daineka ◽  
Guili Zhao ◽  
Nataliya Kundikova
Keyword(s):  
Protective Coatings ◽  
Front Surface ◽  
Silver Surface ◽  
Ecr Plasma ◽  
Minimal Thickness ◽  
Local Defects ◽  
Sulfur Containing ◽  
Different Thickness ◽  
Deposited Films ◽  
Better Than

Protection of silver surface from corrosion is an important topic, as this metal is highly susceptible to damage by atomic oxygen, halogenated, acidic and sulfur-containing molecules. Protective coatings need to be efficient at relatively small thicknesses, transparent and must not affect the surface in any detrimental way, during the deposition or over its lifetime. We compare PECVD-deposited SiNx films to efficiency of ALD-deposited AlOx films as protectors of front surface silver mirrors against damage by oxygen plasma. Films of different thickness were deposited at room temperature and exposed to O2 ECR-plasma for various durations. Results were analyzed with optical and SEM microscopy, pulsed GD-OES, spectroscopic ellipsometry and spectrophotometry on reflection. Studies indicate that both films provide protection after certain minimal thickness. While this critical thickness seems to be smaller for SiNx films during short plasma exposures, longer plasma treatment reveals that the local defects in PECVD-deposited films (most likely due to erosion of some regions of the film and pinholes) steadily multiply with time of treatment and lead to slow drop of reflectance of SiNx-protected mirrors, whereas we showed before that ALD-deposited AlOx films reliably protect silver surface during long plasma exposures.

NbN Thin Film of Alternating Textures

2017 ◽  
Vol 898 ◽  
pp. 1431-1437
Author(s):  
Hong Yang Shao ◽  
Kan Zhang ◽  
Yi Dan Zhang ◽  
Mao Wen ◽  
Wei Tao Zheng
Keyword(s):  
Deposition Time ◽  
Peak Position ◽  
Preferred Orientation ◽  
Intrinsic Stress ◽  
Competitive Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Orientation Distributions ◽  
Different Thickness ◽  
Deposited Films

The δ-NbN thin films with different thickness have been prepared by reactive magnetron sputtering at different deposition time and exhibited alternating textures between (111) and (200) orientations as a function of thickness. In addition, the grain size, peak position, morphology, residual stress and orientation distributions of the deposited films were explored by X-ray diffraction, low-angel X-ray reflectivity, scanning electron microscopy and surface profiler. The film deposited at 300 s showed a (111) preferred orientation, changing to (200) preferred orientation at 600 s, and exhibited alternating textures between (111) and (200) preferred orientations. With further increasing deposition time, in which (200) peak position and the full width at half maximum of (111) peak also displayed a trend of alternating variation with varying deposition time. The intrinsic stress for δ-NbN films calculated by Stoney equation alternately changed with alternating textures, in which (111) orientation always takes place at relatively high intrinsic stress state and vice versa. Meanwhile, the film with (111) preferred orientation showed higher density than (200) preferred orientation. The film deposited at 4800 s owned a mixed texture of (111) and (200), showing an anisotropy distribution of (111)-oriented and (200)-oriented grains, while film deposited at 7200 s owned a strong (200) texture, displaying an isotropy distribution of (200)-oriented grains. The competitive growth between (111)-oriented and (200)-oriented grains was responsibility for alternating texture.

Diamond-like carbon-deposited films: a new class of biocorrosion protective coatings

2018 ◽  
Vol 6 (4–5) ◽  
pp. 266-276 ◽  
Author(s):  
Mohammad Reza Derakhshandeh ◽  
Mohammad Javad Eshraghi ◽  
Masoumeh Javaheri ◽  
Sara Khamseh ◽  
Morteza Ganjaee Sari ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Diamond Like Carbon ◽  
New Class ◽  
Deposited Films

Ion-Assisted Deposition of CaF2 Films on (111) Si

1992 ◽  
Vol 268 ◽  
Author(s):  
J.G. Cook ◽  
H. Moeller ◽  
S.R. Das ◽  
Li Zhongming
Keyword(s):  
Optical Properties ◽  
Emission Spectroscopy ◽  
Rf Discharge ◽  
Electrical And Optical Properties ◽  
Sputter Deposited ◽  
Deposited Films ◽  
Better Than

ABSTRACTCaF2 films have been deposited by evaporation onto H-passivated (111) Si in the presence of an rf discharge. The discharge is seen to promote epitaxy. Emission spectroscopy reveals strong CaF2 bands and a weak Ca line, indicating that deposition is largely molecular but that some breakup of the CaF2 molecules occurs in the discharge. Electrical and optical properties of these films were substantially better than those of sputter-deposited films.

Sol-Gel Protective Films for Metal Solar Mirrors

1988 ◽  
Vol 121 ◽  
Author(s):  
Scott Reed ◽  
Carol Ashley
Keyword(s):  
Protective Coatings ◽  
Sol Gel ◽  
Protective Layer ◽  
Front Surface ◽  
Optical Measurements ◽  
Preliminary Evaluation ◽  
Environmental Testing ◽  
Specular Reflectance ◽  
Outdoor Environments ◽  
Sputter Deposited

ABSTRACTFront-surface metal mirrors were coated with a variety of sol-gel derived glass films for preliminary evaluation as protective coatings for silver. Optical measurements (hemispherical, diffuse and specular reflectance) were used to characterize changes in the mirror resulting from the application of the sol, subsequent processing, or environmental testing. The abrasion resistance of the films was determined on sol-gel coated silicon wafers per ASTM procedures. The mirrors were exposed to outdoor environments in Albuquerque, N.M., as well as accelerated testing in H2SO4, with periodic monitoring of optical properties. A two layer coating scheme, consisting of a thin primary protective layer of sputter deposited SiO2 followed by a thicker sol-gel overcoat, was also evaluated.

scholarly journals Protective coatings for front surface silver mirrors by atomic layer deposition

2020 ◽  
Vol 28 (11) ◽  
pp. 15753
Author(s):  
Pavel Bulkin ◽  
Sofia Gaiaschi ◽  
Patrick Chapon ◽  
Dmitri Daineka ◽  
Natalya Kundikova
Keyword(s):  
Atomic Layer Deposition ◽  
Protective Coatings ◽  
Front Surface ◽  
Atomic Layer ◽  
Layer Deposition

Reproducibility of vacuum deposited films of amorphous ZnTe

1981 ◽  
Vol 59 (7) ◽  
pp. 924-928 ◽  
Author(s):  
C. J. Moore ◽  
B. S. Bharaj ◽  
D. E. Brodie
Keyword(s):  
Electrical Conductivity ◽  
High Purity ◽  
Vacuum Deposition ◽  
Amorphous Films ◽  
Deposition Parameters ◽  
Ambient Gases ◽  
Residual Gas ◽  
First Time ◽  
Deposited Films ◽  
Better Than

The temperature dependence of the electrical conductivity of high purity amorphous ZnTe films has been measured and compared for films produced in the same way, and some films produced with different deposition parameters. We have demonstrated (probably for the first time) that pure vacuum deposited amorphous films can be fabricated with sample conductivities reproduced to better than a factor of two (14 samples over a two year period) between ~100 and ~400 K. This work was made possible with the help of a microprocessor monitored vacuum deposition system with a base pressure of 10−9 Torr. In addition, it is shown that samples fabricated in a system at a pressure of 10−6 Torr have conductivities which depend on the nature of the residual gas in the system because the sample conductivity varies significantly when different ambient gases are introduced.

Fatigue Characteristic of Aluminum Alloy Plates with Different Thickness

2013 ◽  
Vol 477-478 ◽  
pp. 1284-1287 ◽  
Author(s):  
Hai Gen Jian ◽  
Min Xian Du ◽  
Feng Jiang ◽  
Zhi Min Yin
Keyword(s):  
Grain Size ◽  
Aluminum Alloy ◽  
Grain Boundaries ◽  
Fatigue Behavior ◽  
Propagation Direction ◽  
Fatigue Characteristic ◽  
Transmission Electron ◽  
Resistance Performance ◽  
Different Thickness ◽  
Better Than

The fatigue characteristic of 2124 aluminum alloy in T851 condition was investigated by means of scanning electron microscopy (SEM) and transmission electron microscope (TEM). And the result shows that, the fatigue life is closely related to the thickness of plates, this is because that different thickness of plates results in the variation of grain size, grain boundaries and substructures of alloy, which thus influence the fatigue behavior of 2124-T851 alloy. The number of grain boundaries along the propagation direction of cracks and the amount of substructures after heat treatment increase with the decline of thicknesses of 2124 alloy plates, while the grain size is reverse. However, no obvious size and dispersion changes for the precipitates. Comparatively, the fatigue resistance performance of 30mm thickness plate is better than the 40mm and 55mm thickness plates, which is due to the more profitable grain size, grain boundary and substructure.

scholarly journals Ta2O5Thin Films for Capacitive RF MEMS Switches

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Anna Persano ◽  
Fabio Quaranta ◽  
Adriano Cola ◽  
Antonietta Taurino ◽  
Giorgio De Angelis ◽  
...  
Keyword(s):  
Thin Films ◽  
Rf Mems ◽  
Electrical Characterization ◽  
Mems Switches ◽  
Dielectric Layers ◽  
Rf Mems Switches ◽  
High Dielectric ◽  
Deposited Films ◽  
Better Than

Shunt capacitive RF MEMS switches have been developed using III-V technology and employing (tantalum pentoxide) Ta2O5thin films as dielectric layers. In order to evaluate the potential of the Ta2O5thin films for the considered application, the compositional, structural, and electrical characterization of the deposited films has been performed, demonstrating that they are good candidates to be used as dielectric layers for the fabrication of RF MEMS switches. Specifically, Ta2O5films are found to show a leakage current density of few nA/cm2forE∼1 MV/cm and a high dielectric constant of 32. Moreover, the charging process has been investigated, finding that it follows a stretched exponential law. The fabricated switches show actuation voltages in the range 15–20 V, an insertion loss better than −0.8 dB up to 30 GHz, and an isolation of ~−40 dB at the resonant frequency which is around 25 GHz.

scholarly journals Preconcentration And Determination Of Precious Metals Using Silica Gel Chemically Modified With Products Of Interaction Of O- or p-Aminotiophenols With g-(Trietoxisilane)Propylisocyanate

2020 ◽  
Vol 15 (2) ◽  
pp. 53-56
Author(s):  
A.K. Trofimchuk ◽  
V.N. Losev ◽  
V.V. V.V. ◽  
E.V. Elsuf’ev ◽  
N.V. Gudymа
Keyword(s):  
Precious Metals ◽  
Silica Gels ◽  
Luminescence Spectroscopy ◽  
Surface Complexes ◽  
Chemically Modified ◽  
Gold Silver ◽  
Lower Oxidation ◽  
Sulfur Containing ◽  
Better Than

The synthesis of new complexing adsorbents with thiophenol (MPhS) and aminobenzthiazolpropyl (ABTS) groups grafted onto the surface of silica gels are considered. The extraction of precious metals (Au(III), Ag(I), Pd(II), Pt(II,IV), Rh(III), Ir(IV), Ru(IV), Os(IV)) from solutions of hydrochloric acid by MPhS and ABTS adsorbents. Contact time, acidity, temperature (25 – 95 °C), and the presence of a labilization agent tin(II) chloride is examined. It is shown that the adsorption properties of MPhS for precious metals are better than ABTS. It was proved by luminescence spectroscopy that gold, silver and platinum in the surface complexes with sulfur-containing groups are in lower oxidation states; and by the EPR method it was proved that ruthenium and osmium in surface complexes are in oxidation state +3. The formation of luminescent Ag(I), Au(I) and Pt(II) complexes on the surface of the MPhS, colored Ru(III) complexes on the surface of MPhS and ABTS, and mixed-ligand complexes of Pt(II) with surface aminobenzthiazole groups and Michler’s thioketone were used for developing methods of their adsorption luminescent, adsorption-photometric and test determinatio

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