Ferroelectric PbTiO3 films grown by pulsed liquid injection MOCVD

Abstract

The influence of deposition conditions (pressure, growth rate, solution concentration, etc.) on the growth of ferroelectric PbTiO 3 (PTO) films by pulsed liquid injection MOCVD was examined. Pb(thd) 2 and Ti(O i Pr) 2 (thd) 2 (thd = 2,2,6,6-tetramethyl-3,5-heptanedionate) dissolved in toluene were used as precursors. Films were grown on LaAlO 3 (001) substrates for deposition process optimisation. PbTiO 3 /La 1-x Sr x MnO 3 /LaAlO 3 heterostructures were elaborated at optimized deposition conditions. The microstructure of the heterostructures was characterized by X-ray Diffraction and by Raman spectroscopy. Pt/PbTiO 3 /La 1-x Sr x MnO 3 /LaAlO 3 structures were used for ferroelectric, dielectric and piezoelectric characterisations of PTO films.

Ferroelectric domains in epitaxial PbTiO3 films on LaAlO3 substrate investigated by piezoresponse force microscopy and far-infrared reflectance

“…33,34 Deposition took place at about 650 C, i.e., nominally under a 4.1% compressive "cube-to-cube" epitaxial strain. 35 Film thicknesses were measured from film cross-section micrographs obtained by scanning electron microscopy.…”

Raman spectroscopy and X-ray diffraction studies of stress effects in PbTiO/sub 3/ thin films

“…The injector consists of a computer-driven, high-speed, precision electromagnetic valve operating under a repetitive pulsing regime. The deposition conditions were optimized in order to obtain a pure and high quality PTO perovskite phase (bulk lattice parameters a = 3.899Å and c = 4.153Å) deposited on an LAO substrate (a = 3.791Å, supplied by CrysTec GmbH, Berlin, Germany) with the surface cut parallel to a (00l) plane (indices refer to the pseudo-cubic setting) [35], [36]. Films of different thickness from 30 to 460 nm were deposited at 650 • C. The thicknesses were measured from the film cross-section micrographs obtained by scanning electron microscopy (SEM).…”

Residual stress estimation in ferroelectricPbTiO3thin films by Raman spectroscopy

“…More details concerning deposition techniques and standard sample characterization can be found elsewhere. 34,35 Raman spectra were collected using a Jobin-Yvon/Horiba LabRam spectrometer equipped with a N 2 -cooled charge coupled device ͑CCD͒ detector. Experiments were conducted in the micro-Raman mode at room temperature in backscattering geometry.…”