Li′na CHENG
材料科学技术(英文)
Microstructural characteristics in the BaSrNb0:3Ti0:7O3 thin film, grown on SrTiO3 substrate by computercontrolled laser molecular beam epitaxy, were characterized by means of transmission electron microscopy (TEM). It is found that the film is single-crystallized and epitaxially grown on the SrTiO3 substrate forming a flat and distinct interface. Anti-phase domains were identified, and the crystallographic features of mismatch dislocations at the interface between film and substrate were clarified. The high conductivity of the present film was discussed from the viewpoint of Nb dopant and the nitrogen atmosphere.
关键词:
BaSrNb0.3Ti0.7O3 thin film
,
thin
,
film
,
epitaxial
,
gro
Lijuan ZHANG
,
Mike L.JENKINS
,
Glyn TAYLO
,
null
,
null
,
null
材料科学技术(英文)
The effects of preparation and crystal growth methods on the microstructure, composition, and oxidation of CoTi(Zr) intermetallics were dealt with . A group of methods has been used to produce CoTi and CoTi(Zr) crystals to prevent the formation of titanium oxide particles during melting and crystal growth. The results show that more oxides formed when using powdered starting materials even though the metals handled were and melted under an inert gas atmosphere; using bulk starting materials produced alloys showed less oxidation than powders, but adding a small amount of Al to getter the oxygen was not sufficient to prevent TiO2 formation. However, using a slightly reducing atmosphere during initial melting was highly effective in reducing the formation of oxide. Crystal growth carried out in Ar did not reduce the amount of oxide but only redistributed the particles. TiO2 particles were found only in the grain boundaries after crystal growing, where they obstructed grain growth. Crystal growth in a vacuum was found to be essential in producing oxide free crystals. A seed selection technique was developed and used in growing CoTi single crystals. The microstructures of the samples were determined using optical microscopy, scanning electron microscopy and transmission electron microscopy, including the morphologies, grain sizes, oxide distributions and crystal structure confirmation.
关键词:
CoTi
,
CoTi(Zr)
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Intermetallics
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Crystal
,
gro