Substrate surface engineering for tailoring properties of functional ceramic thin films

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

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The crystallization of thin-film ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122095 ◽

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.

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{10} edge dislocations in YSZ films grown on (100)MgO by PLD

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170384 ◽

1994 ◽

Vol 52 ◽

pp. 530-531

Author(s):

Jason R. Heffelfinger ◽

C. Barry Carter

Keyword(s):

Thin Films ◽

Semiconductor Lasers ◽

Vapor Deposition ◽

Substrate Surface ◽

Laser System ◽

Average Energy ◽

Target Material ◽

Chemical Vapor ◽

Buffer Layers ◽

Organic Chemical

Yttria-stabilized zirconia (YSZ) is currently used in a variety of applications including oxygen sensors, fuel cells, coatings for semiconductor lasers, and buffer layers for high-temperature superconducting films. Thin films of YSZ have been grown by metal-organic chemical vapor deposition, electrochemical vapor deposition, pulse-laser deposition (PLD), electron-beam evaporation, and sputtering. In this investigation, PLD was used to grow thin films of YSZ on (100) MgO substrates. This system proves to be an interesting example of relationships between interfaces and extrinsic dislocations in thin films of YSZ.In this experiment, a freshly cleaved (100) MgO substrate surface was prepared for deposition by cleaving a lmm-thick slice from a single-crystal MgO cube. The YSZ target material which contained 10mol% yttria was prepared from powders and sintered to 85% of theoretical density. The laser system used for the depositions was a Lambda Physik 210i excimer laser operating with KrF (λ=248nm, 1Hz repetition rate, average energy per pulse of 100mJ).

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970 nm Infrared to Visible Upconversion in Er3+ and Yb3+ Co-Doped PLZT Glass Ceramic Thin Films

10.1557/proc-1111-d04-03 ◽

2008 ◽

Author(s):

Xiaomei Guo ◽

Kewen Kevin. Li ◽

Xuesheng Chen ◽

Yingyin Kevin. Zou ◽

Hua Jiang

Keyword(s):

Thin Films ◽

Glass Ceramic ◽

Ceramic Thin Films ◽

Co Doped

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Epitaxial Growth of Sr0.3Ba0.7Nb2O6 Thin Films Prepared by Sol-Gel Process

MRS Proceedings ◽

10.1557/proc-606-181 ◽

1999 ◽

Vol 606 ◽

Cited By ~ 2

Author(s):

Keishi Nishio ◽

Jirawat Thongrueng ◽

Yuichi Watanabe ◽

Toshio Tsuchiya

Keyword(s):

Thin Film ◽

Thin Films ◽

Epitaxial Growth ◽

Raw Materials ◽

Substrate Surface ◽

Sol Gel ◽

Tungsten Bronze ◽

Monomethyl Ether ◽

Tetragonal Tungsten Bronze ◽

Sol Gel Process

AbstructWe succeeded in the preparation of strontium-barium niobate (Sr0.3Ba0.7Nb2O6 : SBN30)that have a tetragonal tungsten bronze type structure thin films on SrTiO3 (100), STO, or La doped SrTiO3 (100), LSTO, single crystal substrates by a spin coating process. LSTO substrate can be used for electrode. A homogeneous coating solution was prepared with Sr and Ba acetates and Nb(OEt)5 as raw materials, and acetic acid and diethylene glycol monomethyl ether as solvents. The coating thin films were sintered at temperature from 700 to 1000°C for 10 min in air. It was confirmed that the thin films on STO substrate sintered above 700°C were in the epitaxial growth because the 16 diffraction spots were observed on the pole figure using (121) reflection. The <130> and <310> direction of the thin film on STO were oriented with the c-axis in parallel to the substrate surface. However, the diffraction spots of thin film on LSTO substrate sintered at 700°C were corresponds to the expected pattern for (110).

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Surface engineering of electrodeposited cuprous oxide (Cu2O) thin films: effect on hydrophobicity and LP gas sensing

Applied Surface Science ◽

10.1016/j.apsusc.2021.150020 ◽

2021 ◽

pp. 150020

Author(s):

K.N.D. Bandara ◽

K.M.D.C. Jayathilaka ◽

D.P. Dissanayake ◽

J.K.D.S. Jayanetti

Keyword(s):

Thin Films ◽

Cuprous Oxide ◽

Surface Engineering ◽

Gas Sensing ◽

Cu2o Thin Films

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Observations on the Growth of YBa2Cu3O7 Thin Films at Very High Laser Fluences

MRS Proceedings ◽

10.1557/proc-388-67 ◽

1995 ◽

Vol 388 ◽

Cited By ~ 2

Author(s):

Rand R. Biggers. ◽

M. Grant Norton ◽

I. Maartense ◽

T.L. Peterson ◽

E. K. Moser ◽

...

Keyword(s):

Thin Films ◽

Substrate Surface ◽

Chemical Vapor ◽

Growth Conditions ◽

Organic Chemical ◽

High Fluences ◽

Laser Fluences ◽

High Laser ◽

High Laser Fluences ◽

Very High

AbstractThe pulsed-laser deposition (PLD) technique utilizes one of the most energetic beams available to form thin films of the superconducting oxide YBa2Cu3O7 (YBCO). IN this study we examine the growth of YBCO at very high laser fluences (25 to 40 J/cm2); a more typical fluence for PLD would be nearer to 3 J/cm2. the use of high fluences leads to unique film microstructures which, in some cases, appear to be related to the correspondingly higher moveabilities of the adatoms. Films grown on vicinal substrates, using high laser fluences, exhibited well-defined elongated granular morphologies (with excellent transition temperature, Tc, and critical current density, Jc). Films grown on vicinal substrates using off-axis magnetron sputtering, plasma-enhanced metal organic chemical vapor deposition (PE-MOCVD), or PLD at more typical laser fluences showed some similar morphologies, but less well-defined. Under certain growth conditions, using high laser fluences with (001) oriented substrates, the YBCO films can exhibit a mixture of a- and c-axis growth where both crystallographic orientations nucleate on the substrate surface at the same time, and grow in concert. the ratio of a-axis oriented to c-axis oriented grains is strongly affected by the pulse repetition rate of the laser.

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Preparation and Properties of Superconducting thin Films by Excimer Laser Ablation

MRS Proceedings ◽

10.1557/proc-191-147 ◽

1990 ◽

Vol 191 ◽

Author(s):

Michael E. Geusic ◽

Alan F. Stewart ◽

Larry R. Pederson ◽

William J. Weber ◽

Kenneth R. Marken ◽

...

Keyword(s):

Thin Films ◽

Laser Ablation ◽

Excimer Laser ◽

Laser Energy ◽

Substrate Surface ◽

Xrd Analysis ◽

Zero Field ◽

Superconducting Transition ◽

X Ray Diffraction ◽

Excimer Laser Ablation

ABSTRACTExcimer laser ablation with an in situ heat treatment was used to prepare high quality superconducting YBa2Cu3O7−x thin films on (100)-SrTiO3 and (100)-LaAlO3 substrates. A pulsed excimer laser (XeCl; 308 nm) was used to ablate a rotating, bulk YBa2Cu3O7−x target at a laser energy density of 2–3 J/cm2. Based on four-probe dc resistance measurements, the films exhibited superconducting transition temperatures (Tc, midpoint) of 88 and 87K with 2K (90–10%) transition widths for SrTiO3 and LaAlO3, respectively. Transport critical current densities (Jc) measured at 77K were 2 × 106 and 1 × 106 A/cm2 in zero field for SrTiO3 and LaAlO3, respectively. X-ray diffraction (XRD) analysis showed the films to be highly oriented, with the c-axis perpendicular to the substrate surface.

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