Thin film sensors on the basis of chalcogenide glass materials prepared bypulsed laser deposition technique

Potentiometric thin film sensors on the basis of the two different chalcoge nide glass materials Ag-As-S and Cu-Ag-As-Se-Te have been prepared by means of the pulsed laser deposition (PLD) technique onto Si/SiO2 substrates wit h an additional contact layer of Cr/Au and Ti/Pt, respectively. The physica l layer structure and the stoichiometric composition of the deposited glass materials have been investigated by means of Rutherford backscattering spe ctrometry (RBS) and transmission electron microscopy (TEM). Depending on th e material systems used, in a conventional "two-electrodes" measuring set-u p, these novel thin film sensors possess a high sensitivity towards lead (2 3-25 mV/pPb), copper (29-31 mV/pCu), cadmium (23-27 mV/pCd) and silver (abo ut 54 mV/pAg) over a measuring period of more than 60 days. The obtained re sults are in good accordance when comparing them to measurements performed with conventional bulk ion-selective electrodes, built-up of the same layer composition. (C) 2000 Elsevier Science S.A. All rights reserved.