Laser transfer processing and the integration of ferroelectric films

Abstract

Thin films of barium strontium titanate (BST), lanthanum modified bismuth titanate (LBT) and lead zirconate titanate (PZT) were fabricated by sol-gel methods onto sapphire substrates. They were transferred to a second substrate by using UV excimer laser radiation to delaminate the films from the fabrication substrate. Scanning electron microscopy revealed melting at the interfacial region of the LBT and PZT films, thus providing the delamination mechanism, but melting was not observed in the BST films. Only the PZT film, after laser transfer, retained its ferroelectric properties, with remnant polarisation of ~30 C/cm2, and a high coercive field of 150 kV/cm.