Impedance spectroscopy and relaxation phenomena of (Na,K) excess Na0.5K0.5NbO3 thin films grown by chemical solution deposition

• Published in: Thin solid films Vol. 519; no. 2; pp. 947 - 951
• Main Authors: Lee, Sun Young, Kim, Jin Soo, Ahn, Chang Won, In Hwang, Hak, Kim, Ill Won
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 01.11.2010
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition; Electrical conduction; Electrical properties of specific thin films; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Frequency ranges; Grain boundaries; Growth from solutions; Impedance; Impedance spectroscopy; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Materials science; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Thin films; Titanium; Grain boundaries; Temperature dependence; Crystal defects; Frequency dependence; Liquid phase deposition; Ferroelectric property; Electrical conductivity; Potassium niobates; Dielectric properties; Crystallization; Sodium niobates; XRD; Impedance spectroscopy; K; Thin films; Interfaces; Hysteresis loop; Relaxation; Chemical solution deposition; Na; Ferroelectric materials; Crystal growth from solutions; NbO; Ferroelectric hysteresis
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.08.133

Na0.5K0.5NbO3 (NKN) and 10mol% (Na,K) excess Na0.5K0.5NbO3 (NKN10) thin films on Pt/Ti/SiO2/Si substrate were prepared by chemical solution deposition. Crystallization of NKN10 thin films was confirmed by X-ray diffraction. The (Na,K) excess Na0.5K0.5NbO3 thin film shows a ferroelectric P-E hysteresis loop. Dielectric properties and impedance spectroscopy of thin films were investigated in the frequency range from 0.1Hz to 100kHz and the temperature range of 25~500AC. By analyzing the complex impedance relaxation with Cole-Cole plots, we found impedance relaxations for the thin film. The contribution of electrical conduction is discussed in relation to grain, grain boundary, and interface effects.