Preferential Orientation of Photochromic Gadolinium Oxyhydrides

2020 ◽  
Author(s):  
Elbruz Murat Baba ◽  
Jose Montero ◽  
Dmitrii Moldarev ◽  
Marcos V. Moro ◽  
Max Wolff ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Rare Earth ◽  
Preferential Orientation ◽  
Reactive Magnetron ◽  
Flow Ratio ◽  
Deposition Pressure ◽  
Step Process ◽  
Oxidation In Air ◽  
Key Parameter

<p>We report preferential orientation control in photochromic gadolinium oxyhydride (GdHO) thin films deposited by a two-step process. Gadolinium hydride (GdH<sub>2-x</sub>) films were grown by reactive magnetron sputtering, followed by oxidation in air. The preferential orientation, grain size, anion concentrations, and photochromic response of the films are strongly dependent on the deposition pressure. GdHO films show preferential orientation along the [100] direction and exhibit photochromism when synthesized at deposition pressures up to 5.8 Pa and. The photochromic contrast is larger than 20 % when the films are deposited below 2.8 Pa with 0.22 H<sub>2</sub>/Ar flow ratio. We argue that the degree of preferential orientation defines the oxygen concentration which is known to be a key parameter for photochromism in rare-earth oxyhydride thin films. The experimental observations described above are explained by the oxidation-induced decrease of the grain size as a result of the increase of the deposition pressure of the sputtering gas. </p>

Preferential Orientation of Photochromic Gadolinium Oxyhydrides

2020 ◽  
Author(s):  
Elbruz Murat Baba ◽  
Jose Montero ◽  
Dmitrii Moldarev ◽  
Marcos V. Moro ◽  
Max Wolff ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Rare Earth ◽  
Preferential Orientation ◽  
Reactive Magnetron ◽  
Flow Ratio ◽  
Deposition Pressure ◽  
Step Process ◽  
Oxidation In Air ◽  
Key Parameter

<p>We report preferential orientation control in photochromic gadolinium oxyhydride (GdHO) thin films deposited by a two-step process. Gadolinium hydride (GdH<sub>2-x</sub>) films were grown by reactive magnetron sputtering, followed by oxidation in air. The preferential orientation, grain size, anion concentrations, and photochromic response of the films are strongly dependent on the deposition pressure. GdHO films show preferential orientation along the [100] direction and exhibit photochromism when synthesized at deposition pressures up to 5.8 Pa and. The photochromic contrast is larger than 20 % when the films are deposited below 2.8 Pa with 0.22 H<sub>2</sub>/Ar flow ratio. We argue that the degree of preferential orientation defines the oxygen concentration which is known to be a key parameter for photochromism in rare-earth oxyhydride thin films. The experimental observations described above are explained by the oxidation-induced decrease of the grain size as a result of the increase of the deposition pressure of the sputtering gas. </p>

scholarly journals Preferential Orientation of Photochromic Gadolinium Oxyhydride Films

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3181 ◽  
Author(s):  
Elbruz Murat Baba ◽  
Jose Montero ◽  
Dmitrii Moldarev ◽  
Marcos Vinicius Moro ◽  
Max Wolff ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Preferential Orientation ◽  
Reactive Magnetron ◽  
Flow Ratio ◽  
Deposition Pressure ◽  
Step Process ◽  
Oxidation In Air ◽  
Post Deposition ◽  
Key Parameter

We report preferential orientation control in photochromic gadolinium oxyhydride (GdHO) thin films deposited by a two-step process. Gadolinium hydride (GdH2-x) films were grown by reactive magnetron sputtering, followed by oxidation in air. The preferential orientation, grain size, anion concentrations and photochromic response of the films were strongly dependent on the deposition pressure. The GdHO films showed a preferential orientation along the [100] direction and exhibited photochromism when synthesized at deposition pressures of up to 5.8 Pa. The photochromic contrast was larger than 20% when the films were deposited below 2.8 Pa with a 0.22 H2/Ar flow ratio. We argue that the relation of preferential orientation and the post deposition oxidation since oxygen concentration is known to be a key parameter for photochromism in rare-earth oxyhydride thin films. The experimental observations described above were explained by the decrease of the grain size as a result of the increase of the deposition pressure of the sputtering gas, followed by a higher oxygen incorporation.

Anisotropic thermal conductivity of rare earth–transition metal thin films

1992 ◽  
Vol 7 (2) ◽  
pp. 329-334 ◽  
Author(s):  
L.J. Shaw-Klein ◽  
T.K. Hatwar ◽  
S.J. Burns ◽  
S.D. Jacobs ◽  
J.C. Lambropoulos
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Rare Earth ◽  
Transition Metal ◽  
Columnar Microstructure ◽  
Deposition Pressure ◽  
Metal Thin Films ◽  
Anisotropic Thermal Conductivity ◽  
Out Of Plane ◽  
Order Of Magnitude

Thermal conductivity measurements were performed on several amorphous rare earth transition metal thin films of varying microstructure. The thermal conductivity perpendicular to the plane of the film, measured by the thermal comparator method, was compared with the thermal conductivity value measured parallel to the plane of the film. The latter value was obtained by converting electrical conductivity values to thermal conductivity via the Wiedemann–Franz relationship. As expected, the columnar microstructure induced during the sputter deposition of the thin films causes an anisotropy in the thermal conductivity values, with the in-plane values consistently lower than the out-of-plane values. The effect is most pronounced for the more columnar films deposited at higher pressure, for which the in-plane thermal conductivity, 0.3 W/mK, is an order of magnitude lower than the out-of-plane thermal conductivity, 4.3 W/mK. The thermal conductivity out of the plane of the film decreased with increasing deposition pressure, due to the decreasing film density.

Annealing Characteristics of Al-Light-Rare-Earth Alloy Thin Films for Microelectronic Conductor Lines

1995 ◽  
Vol 403 ◽  
Author(s):  
Shinji Takayama ◽  
Naganori Tsutsui
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Rare Earth ◽  
Grain Boundaries ◽  
High Temperatures ◽  
Light Rare Earth ◽  
Rare Earth Alloy ◽  
Metallic Compounds ◽  
Al Matrix

AbstractThe addition of La and Pr to Al thin films markedly decreases the grain size of the Al matrix and largely suppresses growth of thermal defects of hillocks and whiskers at high temperatures (350°C – 450°C). A large number of fine metallic compounds of Al11RE3 and/or Al3RE (RE = La and Pr) were segregated in an Al matrix, mostly at grain boundaries, after annealing at 350°C. The resistivities of the films after annealing at the above temperatures show very low values of less than 6 μωcm, without the salient formation of hillocks or whiskers on the film surfaces.

PROPERTIES OF Ta2O5 THIN FILMS DEPOSITED BY DC REACTIVE MAGNETRON SPUTTERING

2009 ◽  
Vol 23 (27) ◽  
pp. 5275-5282 ◽  
Author(s):  
JICHENG ZHOU ◽  
DITIAN LUO ◽  
YOUZHEN LI ◽  
ZHENG LIU
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Surface Characteristics ◽  
Reactive Magnetron Sputtering ◽  
Oxygen Flow ◽  
Root Mean Square Roughness ◽  
Reactive Magnetron ◽  
Flow Ratio ◽  
Dc Reactive Magnetron Sputtering ◽  
Xrd Patterns

Ta 2 O 5 thin films were deposited at different oxygen flow ratio ( O 2/( O 2+Ar) = 10 ~ 80%) by DC reactive magnetron sputtering. Influence of oxygen flow ratio on depositing rate, surface characteristics, microstructure, and optical properties are discussed in this paper. With the increasing of oxygen, deposition rate decreases exponentially, the root mean square roughness and the maximum roughness decrease according to the atom force microscope images. XRD patterns indicate the as-deposited Ta 2 O 5 films are amorphous. Based on the envelop method, the samples' optical constants are calculated from the curve of transmission spectrum. The results indicate that refractive index n increases from 2.01 to 2.20 (λ = 500 nm ) for the oxygen flow ratio increases from 20% to 60%, the extinction coefficient k appears to decrease.

Improved optoelectronic properties in solution-processed epitaxial rare-earth-doped BaSnO3 thin films via grain size engineering

2019 ◽  
Vol 115 (16) ◽  
pp. 162105
Author(s):  
R. H. Wei ◽  
L. Hu ◽  
C. Shao ◽  
X. W. Tang ◽  
X. Luo ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Rare Earth ◽  
Optoelectronic Properties ◽  
Solution Processed ◽  
Rare Earth Doped

Single Phase CuO Thin Films Prepared by Thermal Oxidation in Air with Water Vapor

2015 ◽  
Vol 1109 ◽  
pp. 544-548 ◽  
Author(s):  
Jian Bo Liang ◽  
Xu Yang Li ◽  
Naoki Kishi ◽  
Tetsuo Soga
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Optical Properties ◽  
Water Vapor ◽  
Band Gap ◽  
Thermal Oxidation ◽  
Single Phase ◽  
Optical Band Gap ◽  
Structural And Optical Properties ◽  
Oxidation In Air

Single phase CuO films have been successfully synthesized by thermal oxidation of cupper foil in air with water vapor. The structural and optical properties of CuO films were investigated. It is observed that the grain size increases with increasing the oxidation temperature. The optical band gap of CuO film is determined by the transmittance and reflectance spectra.

Strong temperature-dependent crystallization, phase transition, optical and electrical characteristics of p-type CuAlO2 thin films

2015 ◽  
Vol 17 (1) ◽  
pp. 557-562 ◽  
Author(s):  
Suilin Liu ◽  
Zhiheng Wu ◽  
Yake Zhang ◽  
Zhiqiang Yao ◽  
Jiajie Fan ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Single Step ◽  
Reactive Magnetron ◽  
Electrical Characteristics ◽  
Temperature Dependent ◽  
Step Process ◽  
Post Annealing ◽  
Phase Pure ◽  
P Type

Phase-pure p-type rhombohedral CuAlO2 thin films were successfully prepared by reactive magnetron sputtering with a single-step process (without post-annealing).

The crystallization of thin-film ceramics

1992 ◽  
Vol 50 (1) ◽  
pp. 338-339
Author(s):  
J.M. Schwartz ◽  
L.F. Francis ◽  
L.D. Schmidt ◽  
P.S. Schabes-Retchkiman
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Sol Gel ◽  
Processing Route ◽  
Small Areas ◽  
Ceramic Thin Films ◽  
Complex Shapes ◽  
Sol Gel Process ◽  
Ceramic Precursors ◽  
Crystalline Ceramic

Ceramic thin films and coatings are of interest for electrical, optical, magnetic and thermal barrier applications. Critical for improved properties in thin films is the development of specific microstructures during processing. To this end, the sol-gel method is advantageous as a versatile processing route. The sol-gel process involves depositing a solution containing metalorganic or colloidal ceramic precursors onto a substrate and heating the deposited layer to form a crystalline or non-crystalline ceramic coating. This route has several advantages, including the ability to create tailored microstructures and properties, to coat large or small areas, simple or complex shapes, and to more easily prepare multicomponent ceramics. Sol-gel derived coatings are amorphous in the as-deposited state and develop their crystalline structure and microstructure during heat-treatment. We are particularly interested in studying the amorphous to crystalline transformation, because many key features of the microstructure such as grain size and grain size distribution may be linked to this transformation.

A thiourea additive-based quadruple cation lead halide perovskite with an ultra-large grain size for efficient perovskite solar cells

Nanoscale ◽  
2019 ◽  
Vol 11 (45) ◽  
pp. 21824-21833 ◽  
Author(s):  
Jyoti V. Patil ◽  
Sawanta S. Mali ◽  
Chang Kook Hong
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Solar Cells ◽  
Power Conversion Efficiency ◽  
Conversion Efficiency ◽  
Power Conversion ◽  
Perovskite Solar Cells ◽  
Inorganic Perovskite ◽  
Halide Perovskite ◽  
Lead Halide

Controlling the grain size of the organic–inorganic perovskite thin films using thiourea additives now crossing 2 μm size with >20% power conversion efficiency.

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