Evidence of ferroelectric behaviour in CaCu3Ti4O12 thin films deposited by RF-sputtering

Author(s)

Foschini, Cesar R. ^[1] ; Hangai, Bruno ^[2] ; Ortega, Pedro Paulo ^[2] ; Longo, Elson ^[3] ; Cilense, Mario ^[3] ; Simoes, Alexandre Z. ^[2]

Affiliation

^[1] Sao Paulo State Univ UNESP, Sch Engn Bauru, Av Eng Luiz Edmund C Coube 14-01, BR-17033360 Bauru, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Sch Engn Guaratingueta, Av Dr Ariberto Pereira da Cunha 333, BR-12516410 Guaratingueta, SP - Brazil

^[3] Sao Paulo State Univ UNESP, Chem Inst, R Prof Francisco Degni 55, BR-14800900 Araraquara, SP - Brazil

• Document type: Journal article
• Source: PROCESSING AND APPLICATION OF CERAMICS; v. 13, n. 3, p. 219-228, 2019.
• Web of Science Citations: 0

Abstract

The origin of abnormal ferroelectric and unusual piezoelectricity in the polycrystalline CaCu3Ti4O12 (CCTO) thin films deposited by RF-sputtering on Pt/Ti/SiO2/Si (100) substrates was explored. The CCTO thin films, deposited at room temperature followed by annealing at 600 degrees C for 2 h in a conventional furnace, have a cubic structure with lattice parameter a = 7.379 +/- 0.001 angstrom and without any secondary phases. No polarization loss up to 10(10) switching cycles, with a switched polarization Delta P of 30 mu C/cm(2) measured at 400 kV/cm was evidenced. The piezoelectric coefficient investigated by piezoresponse force microscopy (PFM) was approximately 9.0 pm/V. This may be the very first example of exploring the origin of ferroelectric behaviour for a material that possesses space charge polarization with highly resistive grain boundaries in the polycrystalline state. (AU)

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