A new approach to the study of solid-state reactions in oxide ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170335 ◽

1994 ◽

Vol 52 ◽

pp. 520-521

Author(s):

Paul G. Kotula

Keyword(s):

Thin Film ◽

Solid State ◽

Single Crystal ◽

Buffer Layers ◽

Oxide Thin Film ◽

Solid State Reactions ◽

Single Crystal Substrate ◽

Oxide Ceramics ◽

Intimate Contact ◽

Reaction Bonding

Thin-film reactions have potential applications for the production of buffer layers in heterojunctions and for the reaction bonding of materials. The main drawback to these applications at present isthat the effect of interface morphology on the initial kinetics of solid-state reactions is not well understood. In order to study the kinetics and mechanisms of thin-film reactions in oxide ceramics, a new method has been developed. The approach relies on the production of a well characterized high-quality oxide thin film on a single-crystal oxide substrate which makes up the idealized reaction couple-a ‘single-crystal’ thin film in intimate contact with a single crystal substrate. The thin-film approach localizes the reaction near the surface of the specimen so that conventional cross-sectioning techniques can be utilized. Additionally, the scale of the reaction is of the order of tens of nanometers or less which is ideally suited to high-resolution SEM or conventional TEM.NiO/α-Al2O3 is a model system for the study of solid-state reactions.

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Characterization of NiO thin films on α-Al2O3 before and after heat treatment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015143x ◽

1993 ◽

Vol 51 ◽

pp. 1120-1121

Author(s):

Paul G. Kotula ◽

C. Barry Carter

Keyword(s):

Thin Film ◽

Thin Films ◽

Single Crystal ◽

Reaction Kinetics ◽

Laser Pulses ◽

Buffer Layers ◽

Solid State Reactions ◽

Single Crystal Substrate ◽

Before And After ◽

Α Al2o3

The NiO-α-Al2O3 system is of interest as a model system for the study of phase boundaries and reaction kinetics in oxide ceramics. Such a system is of new importance when one of the constituents is a thin film because the reaction kinetics and its dependence on film microstructure is not well understood. Additionally, solid-state reactions between a thin film and single-crystal substrate can be used to produce buffer layers for heterojunctions.In the present study, thin films of NiO have been grown on single-crystal α-Al2O3 substrates by pulsed-laser ablation (PLA). The PLA system used a KrF (248nm) excimer laser operating at 350 mJ per pulse with a pulse repetition rate of 10 Hz. The laser beam was focused to a spot 1×2mm on the surface of rotating NiO pellet. Films were grown at nominal substrate temperatures of 750°C and oxygen pressures of about 10 mTorr. Films were grown both on bulk substrates for which 6000 laser pulses was used to produce 1000Å films and electron-transparent substrates for which 500 laser pulses was used to produce 80Å films.

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Use of Pt Markers in the Study of Solid-State Reactions in the Presence of an Electric Field

Microscopy and Microanalysis ◽

10.1017/s1431927698980151 ◽

1998 ◽

Vol 4 (2) ◽

pp. 158-163 ◽

Cited By ~ 11

Author(s):

Matthew T. Johnson ◽

Shelley R. Gilliss ◽

C. Barry Carter

Keyword(s):

Thin Film ◽

Solid State ◽

Electric Field ◽

Thin Film Deposition ◽

Film Deposition ◽

Solid State Reactions ◽

Single Crystal Substrate ◽

Fine Scale ◽

Initial Location ◽

Crystal Substrate

The use of Pt to mark the initial location of heterophase boundaries in solid-state reactions was extended to investigate the motion of interfaces during a thin-film solid-state reaction between In2O3 and MgO in the presence of an electric field. The Pt markers were prepared by sputtering a thin Pt film onto a single-crystal substrate. The resulting multilayer was then heated prior to thin-film deposition to de-wet the Pt film and thus form an array of small, isolated particles. These particles serve as fine-scale markers for tracking the motion of interfaces. However, there are certain situations in which the markers can move with the interface.

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Temperature-Dependent Solid-State Reactions With and Without Kirkendall Effect in Al2O3/ZnO, Fe2O3/ZnO, and CoXOY/ZnO Oxide Thin Film Systems

Advanced Engineering Materials ◽

10.1002/adem.201000043 ◽

2010 ◽

Vol 12 (6) ◽

pp. 509-516 ◽

Cited By ~ 9

Author(s):

Andriy Zolotaryov ◽

Silvana Goetze ◽

Robert Zierold ◽

Dmitri Novikov ◽

Balaji Birajdar ◽

...

Keyword(s):

Thin Film ◽

Solid State ◽

Kirkendall Effect ◽

Oxide Thin Film ◽

Solid State Reactions ◽

Temperature Dependent

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Texture Effects in Solid-State Reactions of Thin Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.706-709.2857 ◽

2012 ◽

Vol 706-709 ◽

pp. 2857-2862 ◽

Cited By ~ 1

Author(s):

Koen De Keyser ◽

Christophe Detavernier ◽

Jean Jordan Sweet ◽

Christian Lavoie

Keyword(s):

Thin Films ◽

Solid State ◽

Single Crystal ◽

Phase Formation ◽

Metal Film ◽

Solid State Reactions ◽

Single Crystal Substrate ◽

Crystal Substrate ◽

Semiconductor Single Crystal ◽

Deposited Film

The texture of thin films, originating from a solid state reaction between a deposited film and a single crystal substrate is investigated. The relation between the phase formation and texture is analyzed for a number of these systems, such as Co/Si, Ni/Si or Co/Ge, where a metal film is allowed to react with a semiconductor single crystal substrate during heating and a summary of these results in presented in this article. It was found that the texture of the resulting films can be very complex, consisting of a variety of simultaneously occurring texture components such as epitaxy, fiber and axiotaxy texture. The close connection between the phase formation and texture is demonstrated by the fact that even a small intervention in either one, can have a huge effect on the resulting phase and/or its texture. From this, we show that the effect of the addition of ternary elements (e.g. Pt, W, C) to the thin films can only be understood if one considers its effects on both the kinetics and the thermodynamics of the reactions, as well as on the texture of the phases. We show how this can be used to influence technologically important properties of the films, such of formation temperature or stability.

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