Doping effect of Dy on leakage current and oxygen sensing property of SrTiO3 thin film prepared by PLD

Abstract

Polycrystalline Dy-doped SrTiO3 thin films deposited by pulsed laser deposition (PLD) on CeO2-buffered yttria-stabilized zirconia (YSZ) single crystal substrates showed oxygen sensing characteristics at room temperature. The oxygen gas sensing characteristics depended on the amount of Dy-doping, and 1.5 mol% Dy-doping was most effective. The oxygen gas sensing characteristics were closely related to leakage current characteristics of Dy-doped SrTiO3 thin film deposited on ZnIn2O 2/YSZ/Si(001) substrates. The suppression of leakage current by Dy-doping suggests that Ti4+ is substituted by Dy3+, and the Dy3+ acts as an acceptor. Further doping of Dy3+ brought about the increase of the leakage current, and it lowered the oxygen gas sensitivity.©2009 The Ceramic Society of Japan. All rights reserved.