Integration of piezoelectric (Pb, La)TiO3 on (100)InP by using a CeO2 buffer layer

Abstract

(Pb, La)TiO 3 /CeO 2 /(100)InP multilayers have been prepared by pulsed laser deposition (PLD) using a KrF laser. CeO2 films deposited in a low oxygen pressure (PO2=10−5 mbar) exhibit the coexistence of stoichiometric CeO2 and oxygen deficient CeO2−x phases. The latter can be best avoided by a postdeposition annealing in a higher oxygen pressure (PO2=0.1 mbar). The PLD conditions leading to largest grain size and [111] textured CeO2 are a substrate temperature Ts=575 °C and a laser fluence of 4 J/cm2. (Pb, La)TiO3 films are deposited at Ts=650 °C and PO2=0.1 mbar. The CeO2 buffer stimulates [001] (Pb, La)TiO3 texture. The films have sharp layer interfaces and uniform composition inside their respective layers.