Multicomponent thin films for electrochemical sensor applications prepared by pulsed laser deposition

Thin film sensors on the basis of the different chalcogenide glass materials (PbS-AgI-AsS, CdS-AgI-AsS, Tl-Ag-As-I-S) have been prepared by means of an off-axis pulsed laser deposition technique (PLD). The physical structure and the stoichiometric composition of the deposited glass layers have been investigated by Rutherford backscattering spectrometry (RBS) and transmission electron microscopy (TEM). It is shown that the complex stoichiometry of the chalcogenide target materials is maintained in the chalcogenide thin films prepared by PLD. Depending on the material system used, these novel thin film sensors possess a high sensitivity towards Pb and Cd of 25-29 mV/pX (X = Pb, Cd) and 54-60 mV/pTl over a measuring period of more than 150 days. The obtained results are in good accordance in comparison to measurements performed with bulk sensors. (C) 2001 Elsevier Science B.V. All rights reserved.