Mechanistic interaction study of thin oxide dielectric with conducting organic electrode Article

Sharma, H, Sethi, K, Raj, PM et al. (2012). Mechanistic interaction study of thin oxide dielectric with conducting organic electrode . MATERIALS CHEMISTRY AND PHYSICS, 134(1), 508-513. 10.1016/j.matchemphys.2012.03.024

cited authors

  • Sharma, H; Sethi, K; Raj, PM; Gerhardt, RA; Tummala, R

authors

abstract

  • This paper aims at understanding the interaction of intrinsic conducting polymer, PEDT, with ALD-deposited Al 2O 3 and thermally oxidized Ta 2O 5 dielectrics, and the underlying mechanisms for increase in leakage currents in PEDT-based capacitors. Conducting polymers offer several advantages as electrodes for high surface area capacitors because of their lower resistance, self-healing and enhanced conformality. However, capacitors with in situ polymerized PEDT show poor electrical properties that are attributed to the interfacial interaction between the organic electrode and the oxide dielectric. This study focuses on characterizing these interactions. A combination of compositional, structural and electrical characterization techniques was applied to polymer-solid-state-capacitor to understand the interfacial chemical behavior and dielectric property deterioration of alumina and tantalum-oxide films. XPS and impedance studies were employed to understand the stiochiometric and compositional changes that occur in the dielectric film on interaction with in situ deposited PEDT. Based on the observations from several complimentary techniques, it is concluded that tantalum-pentoxide has more resistance towards chemical interaction with in situ polymerized PEDT. The thermally oxidized Ta 2O 5-PEDT system showed leakage current of 280 nA μF -1 at 3 V with a breakdown voltage of 30 V. On the other hand, Al 2O 3-PEDT capacitor showed leakage current of 50 μA μF -1 and a breakdown voltage of 40 V. The study reports direct evidence for the mechanism of resistivity drop in alumina dielectric with in situ polymerized PEDT electrode. © 2012 Elsevier B.V. All rights reserved.

publication date

  • May 15, 2012

published in

Digital Object Identifier (DOI)

start page

  • 508

end page

  • 513

volume

  • 134

issue

  • 1