Effect of Annealing Temperature on Electrical Properties of BCZT Epitaxial Films and Its Conductivity Mechanism

Abstract

Abstract: The pulsed laser deposition (PLD) technique for the preparation of Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃(BCZT) epitaxial films usually requires high deposition temperature and is prone to contain oxygen vacancy defects. In order to provide a post-annealing treatment process based on PLD, high-quality BCZT epitaxial films were successfully prepared on conductive substrates, and the effects of annealing temperature on the structure and properties of BCZT epitaxial films were investigated. The films annealed at different temperatures of 750, 800, 850 and 900 ℃ show pure phases. The ferroelectric properties of the films are gradually improved as the annealing temperature increase, with 2P_r increasing from 4.2 to 17.6 μC/cm². However, the sample at the annealing temperature of 900 ℃ has the most serious leakage current problem. By fitting the J-E relationship, it is found that the films annealed from 700 ℃ to 850 ℃ follow the Ohmic conduction mechanism at low fields, while the samples annealed at 900 ℃ follow the space charge limited current mechanism, and all the films follow the Fowler-Nordheim tunneling mechanism at high fields.

Key words: pulsed laser deposition, Ba_0.85Ca_0.15Zr_0.1Ti_0.9O₃ epitaxial film, annealing temperature, phase structure, electrical property, conductivity mechanism

CLC Number:

O484

PENG Qianwen, JI Xiang. Effect of Annealing Temperature on Electrical Properties of BCZT Epitaxial Films and Its Conductivity Mechanism[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(1): 82-89.

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