Protective coatings for front surface silver mirrors by atomic layer deposition

Abstract Due to its low cost and suitable band gap, silicon has been studied as a photoanode material for some time. However, as a result of poor stability during the oxygen evolution reaction (OER), Si still remains unsuitable for any extended use. Ultra-thin titanium dioxide (TiO2) films have been used as protective coatings and are shown to enhance Si photoanode lifetime with added solar to hydrogen (STH) performance improvements through distancing the oxidation reaction away from the Si photoanode surface and improved charge transport through the anode. This study details the nucleation, growth chemistry, and performance of TiO2 thin films prepared via thermal and plasma enhanced atomic layer deposition (ALD) using both titanium isopropoxide (TTIP) and Tetrakis(dimethylamido)titanium (TDMAT) as the precursor material. The effect of post ALD treatments of plasma and air annealing was also studied. Films were investigated using photoelectrochemical cell testing to evaluate photoelectrochemical performance, and in-vacuum cycle-by-cycle x-ray photoelectron spectroscopy (XPS) was used as the primary characterisation technique to study nucleation mechanisms and film properties contributing to improvements in cell performance. TiO2 grown by plasma enhanced ALD results in cleaner films with reduced carbon incorporation. However, despite increased carbon incorporation, thermally grown films showed improved photocurrent as a result of oxygen vacancies in these films. Post deposition annealing in a H2 ambient is shown to further improve photocurrent in all cases, while annealing in atmosphere leads to uniform film chemistry and enhanced photocurrent stability in all cases.

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Advanced protective coatings for reflectivity enhancement by low temperature atomic layer deposition of HfO2 on Al surfaces for micromirror applications

Sensors and Actuators A Physical ◽

10.1016/j.sna.2018.09.028 ◽

2018 ◽

Vol 282 ◽

pp. 124-131 ◽

Cited By ~ 6

Author(s):

E. Cianci ◽

A. Lamperti ◽

G. Tallarida ◽

M. Zanuccoli ◽

C. Fiegna ◽

...

Keyword(s):

Low Temperature ◽

Atomic Layer Deposition ◽

Protective Coatings ◽

Atomic Layer ◽

Layer Deposition

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Enhancing the Cycling Stability of Tin Sulfide Anodes for Lithium Ion Battery by Titanium Oxide Atomic Layer Deposition

Journal of Electrochemical Energy Conversion and Storage ◽

10.1115/1.4034809 ◽

2016 ◽

Vol 13 (2) ◽

Cited By ~ 6

Author(s):

Dongsheng Guan ◽

Chris Yuan

Keyword(s):

Atomic Layer Deposition ◽

Structural Integrity ◽

Electrochemical Impedance ◽

Protective Coatings ◽

Lithium Ion ◽

Atomic Layer ◽

Cycling Stability ◽

Tin Sulfide ◽

Transfer Resistance ◽

Layer Deposition

The poor cyclability problem of SnS2 anodes in Li-ion batteries (LIB) is tackled for the first time by surface coatings with TiO2 via atomic layer deposition (ALD). ALD is capable to achieve uniform, conformal nanoscale coatings onto entire SnS2 electrodes, and enhance their cycling stability and rate performance. From our study, we found that the bare electrode delivers capacities eventually down to 219.2 mA h g−1 over 50 cycles, while the ALD TiO2-coated gains a final capacity of 323.7 mA h g−1 (47.7% higher). Electrochemical impedance analyses reveal that the improvement is ascribed to the smaller charge transfer resistance and formation of thinner solid–electrolyte interfaces (SEI) in the coated electrode, thanks to its better structural integrity and less electrolyte decomposition in the presence of protective coatings.

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Porous Alumina Protective Coatings on Palladium Nanoparticles by Self-Poisoned Atomic Layer Deposition

Chemistry of Materials ◽

10.1021/cm300203s ◽

2012 ◽

Vol 24 (11) ◽

pp. 2047-2055 ◽

Cited By ~ 90

Author(s):

Junling Lu ◽

Bin Liu ◽

Jeffrey P. Greeley ◽

Zhenxing Feng ◽

Joseph A. Libera ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Palladium Nanoparticles ◽

Protective Coatings ◽

Porous Alumina ◽

Atomic Layer ◽

Layer Deposition

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Protective coatings of hafnium dioxide by atomic layer deposition for microelectromechanical systems applications

Applied Surface Science ◽

10.1016/j.apsusc.2016.01.216 ◽

2016 ◽

Vol 368 ◽

pp. 470-476 ◽

Cited By ~ 6

Author(s):

Maria Berdova ◽

Claudia Wiemer ◽

Alessio Lamperti ◽

Grazia Tallarida ◽

Elena Cianci ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Microelectromechanical Systems ◽

Protective Coatings ◽

Atomic Layer ◽

Hafnium Dioxide ◽

Layer Deposition

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Plasma Enhanced Atomic Layer Deposition of Tantalum (V) Oxide

Coatings ◽

10.3390/coatings11101206 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1206

Author(s):

Pavel Fedorov ◽

Denis Nazarov ◽

Oleg Medvedev ◽

Yury Koshtyal ◽

Aleksander Rumyantsev ◽

...

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

Photoelectron Spectroscopy ◽

Protective Coatings ◽

Lithium Ion ◽

Atomic Layer ◽

Evaporator Temperature ◽

Current Increase ◽

X Ray ◽

Layer Deposition

The tantalum oxide thin films are promising materials for various applications: as coatings in optical devices, as dielectric layers for micro and nanoelectronics, and for thin-films solid-state lithium-ion batteries (SSLIBs). This article is dedicated to the Ta-O thin-film system synthesis by the atomic layer deposition (ALD) which allows to deposit high quality films and coatings with excellent uniformity and conformality. Tantalum (V) ethoxide (Ta(OEt)5) and remote oxygen plasma were used as tantalum-containing reagent and oxidizing co-reagent, respectively. The influence of deposition parameters (reactor and evaporator temperature, pulse and purge times) on the growth rate were studied. The thickness of the films were measured by spectroscopic ellipsometry, scanning electron microscopy and X-ray reflectometry. The temperature range of the ALD window was 250–300 °C, the growth per cycle was about 0.05 nm/cycle. Different morphology of films deposited on silicon and stainless steel was found. According to the X-ray diffraction data, the as-prepared films were amorphous. But the heat treatment study shows crystallization at 800 °C with the formation of the polycrystalline Ta2O5 phase with a rhombic structural type (Pmm2). The results of the X-ray reflectometry show the Ta-O films’ density is 7.98 g/cm3, which is close to the density of crystalline Ta2O5 of the rhombic structure (8.18 g/cm3). The obtained thin films have a low roughness and high uniformity. The chemical composition of the surface and bulk of Ta-O coatings was studied by X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy. Surface of the films contain Ta2O5 and some carbon contamination, but the bulk of the films does not contain carbon and any precursor residues. Cyclic voltammetry (CVA) showed that there is no current increase for tantalum (V) oxide in a potential window of 3–4.2 V and has prospects of use as protective coatings for cathode materials of SSLIBs.

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