Thin films of cobalt oxides obtained by vacuum co-deposition of Co and TeO2

被引:7
作者
Kitova, S [1 ]
Rashkova, V [1 ]
Konstantinov, I [1 ]
机构
[1] Bulgarian Acad Sci, Acad J Malinowski, Cent Lab Photoproc, BU-1113 Sofia, Bulgaria
关键词
cobalt oxides; thin films; vacuum deposition; thermal effects;
D O I
10.1016/S0042-207X(02)00366-4
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The composition and structure of thin films obtained by vacuum co-deposition of Co and TeO2 in an atomic ratio R-Co/Te = 1.5 are studied. It is shown that during the co-deposition a chemical reaction between both substances takes place resulting in the formation of amorphous CoO phase and elemental Te, very finely dispersed in the amorphous matrix. The reaction in as-deposited films proceeds until the complete oxidation of Co to Co2+. It is found that the crystalline phases of CoO, Co3O4 and/or Te are formed upon thermal heating of the films above 300degreesC. In this case, the reaction proceeds until complete consumption of TeO2 via the oxidation of Co2+ to higher valence and the formation of mixed oxides. (C) 2002 Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:405 / 409
页数:5
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