Temperature dependent dielectric properties and AC conductivity studies on titanium niobium oxide (TiNb2O7) thin films

Daramalla, V and Dutta, S and SB, K (2020) Temperature dependent dielectric properties and AC conductivity studies on titanium niobium oxide (TiNb2O7) thin films. In: Journal of the European Ceramic Society, 40 (4). pp. 1293-1300.

	PDF jou_eur_cer_soc_40-04_1293-1300_2020.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy
	Microsoft Word 1-s2.0-S0955221919307770-mmc1 (1).docx - Published Supplemental Material Restricted to Registered users only Download (1MB) | Request a copy

Abstract

The dielectric properties of TiNb2O7 (TNO) thin films are studied in Metal-Insulator-Metal configuration (Au/TiNb2O7/Pt) devices. The temperature dependence of the dielectric dispersion and the AC conductivity behavior is strongly dependent on TNO thin film thickness. Low thickness (�236 nm) films shows considerably less variation with temperatures than their thicker counterparts (�480 nm). These behaviors are explained on physical basis � nearly constant loss (NCL) and Jonscher's Universal Dielectric Response (UDR). The TNO thin films show large dielectric constant (�59�73) and moderate dielectric loss (�0.07�0.11). The AC conductivity values of the thin films lie in the range of about (10�8 to 10�9) at 10 kHz. The thicker films show DC conductivity values which are thermally activated with an activation energy of about 0.44 eV. This is slightly higher (about 0.1 eV) than �p in Jonscher's UDR response and this discrepancy is explained on the basis of mixed ionic electronic conduction in TNO thin films. The possible role of growth morphology in the dielectric response is also briefly mentioned.

Item Type:	Journal Article
Publication:	Journal of the European Ceramic Society
Publisher:	Elsevier Ltd
Additional Information:	The copyright of this article belongs to Elsevier Ltd
Keywords:	Activation energy; Dielectric losses; Dielectric properties of solids; Dielectric relaxation; Film thickness; Metal insulator boundaries; Morphology; Niobium oxide; Oxide films; Permittivity; Pulsed laser deposition; Temperature distribution; Titanium oxides, High dielectric constants; Large dielectric constant; Metal insulator metals; Mixed ionic-electronic conduction; Nearly Constant Loss; Temperature dependence; Temperature dependent; Universal dielectric response, Thin films
Department/Centre:	Division of Chemical Sciences > Materials Research Centre Division of Interdisciplinary Sciences > Centre for Nano Science and Engineering
Date Deposited:	19 Aug 2020 10:31
Last Modified:	19 Aug 2020 10:31
URI:	http://eprints.iisc.ac.in/id/eprint/64795

Actions (login required)

View Item