Fabrication of tin-based halide perovskites by pulsed laser deposition

Abstract Mixed-organic-cation perovskite absorbers as formamidinium doped methylammonium tin iodine $$(\text {NH}_2\text {CH})_{1-{x}}(\text {CH}_3\text {NH}_3)_x\text {SnI}_3$$ ( NH 2 CH ) 1 - x ( CH 3 NH 3 ) x SnI 3 ($$x\le 1$$ x ≤ 1 ) can provide a pathway to highly efficient lead-free solar cells. Although this class of materials is known to be severely susceptible to degradation, induced among others by enhanced temperatures, humidity and illumination, an improved layer quality in view of crystal size and homogeneity is the key to diminish or even to block certain degradation channels. In this work, we present the fabrication of fully tin-based perovskites via pulsed laser deposition. The morphology is analyzed for different deposition energies and temperatures to find the optimum process window. The thin films already reveal crystalline structure at room temperature, while they are smooth and homogeneous above a critical thickness for carefully adapted deposition parameters. In contrast to the assumption that at elevated temperatures, the crystallinity is improved, and we find that the films reveal a strong organic depletion and simultaneously tin enrichment. As a measure for their suitability to be employed as photovoltaic absorbers, the band gap of the differently doped perovskites is estimated by spectroscopic ellipsometry in the range of 1.3 to 1.4 eV.

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Processing by Pulsed Laser Deposition and Structural, Morphological and Chemical Characterization of Bi-Pb-Sr-Ca-Cu-O and Bi-Pb-Sb-Sr-Ca-Cu-O Thin Films

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.75.202 ◽

2010 ◽

Vol 75 ◽

pp. 202-207

Author(s):

Victor Ríos ◽

Elvia Díaz-Valdés ◽

Jorge Ricardo Aguilar ◽

T.G. Kryshtab ◽

Ciro Falcony

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Room Temperature ◽

Pulsed Laser ◽

Chemical Characterization ◽

Laser Deposition ◽

Nominal Composition ◽

Deposition Parameters ◽

The Relationship

Bi-Pb-Sr-Ca-Cu-O (BPSCCO) and Bi-Pb-Sb-Sr-Ca-Cu-O (BPSSCCO) thin films were grown on MgO single crystal substrates by pulsed laser deposition. The deposition was carried out at room temperature during 90 minutes. A Nd:YAG excimer laser ( = 355 nm) with a 2 J/pulse energy density operated at 30 Hz was used. The distance between the target and substrate was kept constant at 4,5 cm. Nominal composition of the targets was Bi1,6Pb0,4Sr2Ca2Cu3O and Bi1,6Pb0,4Sb0,1Sr2Ca2Cu3OSuperconducting targets were prepared following a state solid reaction. As-grown films were annealed at different conditions. As-grown and annealed films were characterized by XRD, FTIR, and SEM. The films were prepared applying an experimental design. The relationship among deposition parameters and their effect on the formation of superconducting Bi-system crystalline phases was studied.

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Pulsed Laser Deposition of Poly(Tetrafluoroethylene) Films

MRS Proceedings ◽

10.1557/proc-397-223 ◽

1995 ◽

Vol 397 ◽

Cited By ~ 1

Author(s):

D.L. Kjendal ◽

Ashok Kumar ◽

R.B. Inturi ◽

J. A. Barnard

Keyword(s):

Pulsed Laser Deposition ◽

Room Temperature ◽

High Vacuum ◽

Pulsed Laser ◽

Laser Deposition ◽

Deposition Technique ◽

Nano Indentation ◽

Corning Glass ◽

Deposition Parameters ◽

Compositional Properties

ABSTRACTThin films of poly(tetrafluoroethylene) have been deposited on amorphous (7059 Corning Glass) and silicon(l00) substrates at various temperatures by the Pulsed Laser Deposition technique. The deposition was carried out at high vacuum (˜10-6 torr)at temperatures ranging from room temperature to 350°C. The mechanical properties of these films at the varying process temperatures have been evaluated by nano-indentation techniques and compositional properties of the films have been characterized by Fourier Transform Infrared spectroscopy. The deposition parameters have been optimized in order to produce good quality films.

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Synthesis and Characterization of PbO Films Grown by Pulsed Laser Deposition.

MRS Proceedings ◽

10.1557/proc-236-437 ◽

1991 ◽

Vol 236 ◽

Cited By ~ 1

Author(s):

J.S. Zabinski ◽

M.S. Donley ◽

V.J. Dyhouse ◽

R. Moore ◽

N.T. McDevitt

Keyword(s):

Crystal Structure ◽

Substrate Temperature ◽

Partial Pressure ◽

Pulsed Laser Deposition ◽

Room Temperature ◽

Elevated Temperatures ◽

Pulsed Laser ◽

Laser Deposition ◽

Friction Coefficients ◽

X Ray

AbstractLead monoxide (PbO) is a potential solid lubricant for use at elevated temperatures in oxidizing environments. The objective of this research was to grow thin films of PbO by Pulsed Laser Deposition (PLD). Film stoichiometry, crystallinity, and chemistry were adjusted by varying substrate temperature and O2 partial pressure during deposition and the effects of changes in film properties on friction coefficients and wear lives were investigated. Chemistry and crystallinity were evaluated using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and glancing angle X-ray diffraction (XRD). Friction coefficients and wear lives were measured in dry nitrogen and at room temperature using a ball-on-flat tribometer. Films deposited at room temperature retained the crystal structure of the target material, but were oxygen deficient. The O/Pb ratio was increased by raising the O2 partial pressure and by increasing the substrate temperature during deposition; the crystal structure and orientation changed with stoichiometry. Friction coefficients ranged from 0.20 - 0.45 and the wear lives were typically less than those obtained from MoS2 films.

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Thermoelectric properties of epitaxial and topotaxial NaxCoO2 thin films

MRS Proceedings ◽

10.1557/proc-0886-f02-02 ◽

2005 ◽

Vol 886 ◽

Cited By ~ 1

Author(s):

Adyam Venimadhav ◽

Z Ma ◽

Qi Li ◽

A Soukiassian ◽

X. X. Xi ◽

...

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Sapphire Substrate ◽

Room Temperature ◽

Pulsed Laser ◽

Epitaxial Films ◽

Laser Deposition ◽

Vapor Pressures ◽

Film Properties ◽

Deposition Parameters

ABSTRACTWe report structural, electrical, and thermopower properties of epitaxial and topotaxial NaxCoO2 thin films on (0001) sapphire substrate. Topotaxial NaxCoO2 films were prepared by converting an epitaxial Co3O4 film to NaxCoO2 by annealing in Na vapor and epitaxial NaxCoO2 films were obtained by pulsed laser deposition. All the films are c-axis oriented. For topotaxial films, annealing in different Na vapor pressures resulted in films with different Na concentrations, which showed distinct transport properties. For directly deposited epitaxial films by pulsed laser deposition, deposition parameters are found to control the Na concentration and hence the film properties. The largest thermoelectric power of the samples made by different methods is found to be similar in the range of 70-100 μV/K at room temperature

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Synthesis and Characterization of PbO Films Grown by Pulsed Laser Deposition.

MRS Proceedings ◽

10.1557/proc-235-849 ◽

1991 ◽

Vol 235 ◽

Cited By ~ 1

Author(s):

J. S. Zabinski ◽

M. S. Donley ◽

V. J. Dyhouse ◽

R. Moore ◽

N. T. McDevitt

Keyword(s):

Crystal Structure ◽

Substrate Temperature ◽

Partial Pressure ◽

Pulsed Laser Deposition ◽

Room Temperature ◽

Elevated Temperatures ◽

Pulsed Laser ◽

Laser Deposition ◽

Friction Coefficients ◽

X Ray

ABSTRACTLead monoxide (PbO) is a potential solid lubricant for use at elevated temperatures in oxidizing environments. The objective of this research was to grow thin films of PbO by Pulsed Laser Deposition (PLD). Film stoichiometry, crystallinity, and chemistry were adjusted by varying substrate temperature and O2 partial pressure during deposition and the effects of changes in film properties on friction coefficients and wear lives were investigated. Chemistry and crystallinity were evaluated using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and glancing angle X-ray diffraction (XRD). Friction coefficients and wear lives were measured in dry nitrogen and at room temperature using a ball-on-flat tribometer. Films deposited at room temperature retained the crystal structure of the target material, but were oxygen deficient. The O/Pb ratio was increased by raising the O2 partial pressure and by increasing the substrate temperature during deposition; the crystal structure and orientation changed with stoichiometry. Friction coefficients ranged from 0.20 – 0.45 and the wear lives were typically less than those obtained from MoS2 films.

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Growth and Characterization of Hard Nitrides Films Prepared by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-403-283 ◽

1995 ◽

Vol 403 ◽

Cited By ~ 1

Author(s):

R. B. Inturi ◽

Ashok Kumar ◽

U. Ekanayake ◽

N. Shu ◽

J. A. Barnard

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Elevated Temperatures ◽

Pulsed Laser ◽

Laser Deposition ◽

High Temperature Strength ◽

X Ray Diffraction ◽

High Quality ◽

Thin Film Coatings ◽

Deposition Parameters

AbstractTransition metal of nitrides have many desirable properties for application at elevated temperatures because of extremely high melting point, hardness, high temperature strength, good thermal shock resistance, and high thermal conductivity. We have investigated the thin film coatings of nitrides (titanium nitride, and composite carbon nitride) on various commercial useful substrates by the pulsed laser deposition (PLD) method. The PLD method is unique process for depositing high quality thin films with novel microstructure and properties. The laser parameters: energy density, pulse rate, target/substrate distance and substrate temperature have been optimized to improve the quality of thin films. The mechanical properties of the films have been evaluated at different processed conditions by nanoindentation technique. The films were characterized by X-ray diffraction, scanning electron microscope and FTIR techniques. Optimization of laser deposition parameters to obtain high quality thin films will be discussed in detail.

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Annealing Condition Effects on the Structural Properties of FePt Nanoparticles Embedded in MgO via Pulsed Laser Deposition

Nanomaterials ◽

10.3390/nano11010131 ◽

2021 ◽

Vol 11 (1) ◽

pp. 131

Author(s):

Tingting Xiao ◽

Qi Yang ◽

Jian Yu ◽

Zhengwei Xiong ◽

Weidong Wu

Keyword(s):

Pulsed Laser Deposition ◽

Room Temperature ◽

High Vacuum ◽

Pulsed Laser ◽

Annealing Process ◽

Ultra High Vacuum ◽

Laser Deposition ◽

Fept Nanoparticles ◽

Annealing Conditions ◽

Vacuum Atmosphere

FePt nanoparticles (NPs) were embedded into a single-crystal MgO host by pulsed laser deposition (PLD). It was found that its phase, microstructures and physical properties were strongly dependent on annealing conditions. Annealing induced a remarkable morphology variation in order to decrease its total free energy. H2/Ar (95% Ar + 5% H2) significantly improved the L10 ordering of FePt NPs, making magnetic coercivity reach 37 KOe at room temperature. However, the samples annealing at H2/Ar, O2, and vacuum all showed the presence of iron oxide even with the coverage of MgO. MgO matrix could restrain the particles’ coalescence effectively but can hardly avoid the oxidation of Fe since it is extremely sensitive to oxygen under the high-temperature annealing process. This study demonstrated that it is essential to anneal FePt in a high-purity reducing or ultra-high vacuum atmosphere in order to eliminate the influence of oxygen.

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