Effect of sintering conditions on microstructure and dielectric properties of CaCu3Ti4O12 (CCTO) ceramics

The influence of sintering temperature and dwell time on the microstructure formation and dielectric properties of CaCu_(3)Ti_(4)O_(12) ceramics was investigated. For sintering temperatures of 1050 and 1100 °C significant differences in the CaCu_(3)Ti_(4)O_(12) ceramic microstructure and the segrega...

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Detalles Bibliográficos
Autores: Löhnert, Romy, Schmidt, Rainer, Töpfer, Jörg
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/24315
Acceso en línea:https://hdl.handle.net/20.500.14352/24315
Access Level:acceso abierto
Palabra clave:537
Barrier layer capacitor
Constant
Clues.
Electricidad
Electrónica (Física)
2202.03 Electricidad
Descripción
Sumario:The influence of sintering temperature and dwell time on the microstructure formation and dielectric properties of CaCu_(3)Ti_(4)O_(12) ceramics was investigated. For sintering temperatures of 1050 and 1100 °C significant differences in the CaCu_(3)Ti_(4)O_(12) ceramic microstructure and the segregation of a CuO_(x)-rich phase towards the grain boundary (GB) areas were observed with increasing dwell time. In addition to the formation of a semiconducting bulk and insulating grain boundary phase the segregated CuO_(x) forms an intergranular phase, and the effects of this phase on the dielectric properties are rather intriguing. At sintering temperature below 1050 °C only small amounts of CuO_(x) segregate, whereas sintering above 1050 °C (e.g., 1100 °C) leads to increased evaporation of the CuO_(x). Therefore, the effects of the CuOx-rich intergranular phase upon the dielectric properties are felt strongest in samples sintered at 1050 °C. Such effects are discussed in terms of microstructural variations due to liquid phase sintering behavior facilitated by the TiO_(2)-CuO_(x)-eutectic, which appearsto be melted at high sintering temperature prior to evaporation of CuO_(x) at prolonged dwell times at the highest sintering temperatures(1100 °C).