Influence of Oxygen Pressure on Structures and Electrical Properties of Lead-free (K_0.44Na_0.52Li_0.04)(Nb_0.86Ta_0.10Sb_0.04)O₃ Thin Films Deposited by Pulsed Laser Deposition

Abstract

Lead-free ferroelectric (K_0.44Na_0.52Li_0.04)(Nb_0.86Ta_0.10Sb_0.04)O₃ thin films have been prepared by pulsed laser deposition. The structures, morphologies and electrical properties of the thin films have been investigated as a function of oxygen pressure from 10 Pa to 40 Pa. The oxygen pressure plays an important role on the thin films. The crystallization and [001] preferential orientation of the thin films increase with oxygen pressure. The thin film deposited at 30 Pa exhibits the moderate dielectric constant of 1330 at 1 kHz and a well-defined ferroelectric hysteresis loop with the remnant polarization of 8.45 μC/cm² and the coercive field of 27.1 kV/cm.

Keywords:

• Lead-free potassium sodium niobate
• Thin films
• Pulsed laser deposition
• Dielectric and ferroelectric properties

Acknowledgment

This work was supported by the Natural Science Foundation of China (Grant Nos. 90923001 and 51072162), the International Science & Technology Cooperation Program of China (Grant Nos. 2010DFB13640 and 2011DFA51880), the Shaanxi Province International Collaboration Program (Grant Nos. 2009KW-12 and 2010KW-09), and the Shaanxi Science and Technology Promotion Program (2011TG-08).