Sputtered yttrium oxide thin films appropriate for electrochemical sensors

This work deals with Y2O3 thin films prepared by r.f. diode sputtering for application in electrochemical sensors. The influence of annealing on selected electrical and mechanical properties of Y2O3 thin films has been studied. With increasing annealing temperature the values of electrical strength and electrical resistivity increase, whereas, the values of relative permittivity and Young's modulus decrease. Yttrium oxide films have a polycrystalline structure without cubic structural change caused by annealing. The change from compressive to tensile stresses takes place in Y2O3 films with increasing temperature. The properties of Y-2 O-3 thin films are comparable with the published data. The Y2O3 film was used as an insulation layer in vertically arranged electrodes in a microelectrochemical cell. The redox recycling phenomenon was demonstrated with the redox couple [Fe(CN)(6)](3-/4-). (C) 2001 Elsevier Science Ltd. All rights reserved.