Non-ohmic properties of CaCu3Ti4O12 thin films deposited By RF-sputtering

Author(s)

Foschini, C. R. ^[1] ; Hangai, B. ^[2] ; Cavalcante, C. S. ^[2] ; Simoes, A. Z. ^[2] ; Cilense, M. ^[3] ; Longo, E. ^[3]

Affiliation

^[1] Univ Estadual Paulista, UNESP, Fac Engn Bauru, Dept Engn Mecan, Av Eng Luiz Edmundo C Coube 14-01, BR-17033360 Bauru, SP - Brazil

^[2] Univ Estadual Paulista, UNESP, Fac Engn Guaratingueta, Av Dr Ariberto Pereira da Cunha 333, Guaratingueta, SP - Brazil

^[3] Univ Estadual Paulista, UNESP, Inst Quim, Rua Prof Francisco Degni 55, BR-14800900 Araraquara, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS; v. 28, n. 20, p. 15685-15693, OCT 2017.
• Web of Science Citations: 3

Abstract

Calcium copper titanate (CaCu3Ti4O12, CCTO), thin films with polycrystalline nature have been deposited by RF sputtering on Pt/Ti/SiO2/Si (100) substrates at a room temperature followed by annealing at 600 degrees C for 2 h in a conventional furnace. The CCTO thin film present a cubic structure with lattice parameter a = 7.379 +/- 0.001 angstrom free of secondary phases. Dielectric spectroscopy was employed to examine the polycrystalline behaviour of CCTO material and the mechanisms responsible for the barrier-layer capacitances associated with Schottky-type barriers and the non-Ohmic properties. The film presents an electric breakdown field (E-b = 203 V cm(-1)) and then nonlinear coefficient (alpha = 6), which is even lower than that of the ZnO and SnO2 based varistors The observed electrical features of CCTO thin films are highly dependent on the {[}CaO12], {[}CaO4], {[}CuO11], {[}CuO11Vox] and {[}TiO5 center dot V-O(center dot)] clusters. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC