Pulsed laser deposition of polytetrafluoroethylene-gold composite layers

¹ Department of Optics and Quantum Electronics, University of Szeged, 6720 Szeged, Dóm tér 9, Hungary
² MTA-SZTE Research Group on Photoacoustic Spectroscopy, University of Szeged, 6720 Szeged, Dóm tér 9, Hungary

^a e-mail: kega@physx.u-szeged.hu

Received: 11 July 2014
Revised: 11 September 2014
Accepted: 24 September 2014
Published online: 23 October 2014

Abstract

PTFE-metal composites are promising candidates for use as sensor materials. In present study PTFE-Au composite layers were deposited by alternated ablation of pressed Teflon pellets and gold plates with focused beam of an ArF excimer laser at 6 J/cm² fluence, while keeping the substrate at 150 °C temperature. The morphology and chemical composition of the ~3–4 μm average thickness layers was studied by electron microscopy and energy dispersive X-ray spectroscopy. The layers were mainly formed of PTFE gains and clusters which are covered by a conductive Au film. For testing the applicability of such layers as sensing electrodes, composite layers were prepared on one of the two neighbouring electrode of a printed circuit board. Cholesterol and glucose solutions were prepared using 0.1M NaOH solvent containing 10% Triton X-100 surfactant. The electrodes were immersed in the solutions and voltage between the electrodes was measured while a constant current was drawn through the sample. The influence of the analyte concentration on the power spectral density of the voltage fluctuation was studied.