Ž . Applied Surface Science 138–139 1999 552–556 An XPS and XRD study of physical and chemical homogeneity ž / of Pb Zr,Ti O thin films obtained by pulsed laser deposition 3 P. Verardi a,) , F. Craciun a , L. Mirenghi b , M. Dinescu c , V. Sandu d a CNR-Istituto di Acustica ‘O.M. Corbino’, Area di Ricerca Tor Vergata, Via del Fosso del Ca Õaliere 100, I-00133 Rome, Italy b PASTIS-CNRSM, 72100 Brindisi, Italy c Laser Department, INFPLR, PO Box MG-16, RO-76900 Bucharest, Romania d National Institute of Material Physics NIMP, PO Box MG-26, RO-76 900, Bucharest V, Romania Abstract Ž . Ž . Ž . Ž . Pb Zr,Ti O PZT oriented films deposited by laser ablation on Au 111 rSi 111have been tested by different 3 techniques for their physico-chemical homogeneity. The samples have been divided in different zones, in order to verify Ž . existence of chemical and structural differences between different regions. Few techniques like X-ray diffraction XRD an Ž . X-ray photoelectron spectroscopy XPS have been employed for characterization. XRD analysesshowed differences regarding the crystallographic content and the degree of orientation between zones subjected to the plasma arriving at different anglesof incidence on the sample surface. In the same zones XPS studieshave been performed by a VG Ž . ESCALAB 210 Spectrometer, using a non-monochromatic AlK X-ray source300 W in the five channel hemispherical a analyzer. Wide scans in the binding energy scale 0–1200 eV, at 50 eV analyzer pass energy, were collected both from th received surface and after sputter cleaning in order to put into evidence all the constituents of the film. Narrow scans of Ti 2p, Zr 3d, Pb 4f and O 1s were also acquired at 20 eV and 0.1 eVrchannel pass energy and 100 ms of dwell time in orde give a better insight into the chemical bonds form and a semiquantitative analyze of the present chemical species. The piezoelectric properties of different zones were also measured. q 1999 Published by Elsivier Science B.V. All rights reserved. Ž . Keywords: Pb Zr,Ti O thin films; Physical homogeneity; Chemical homogeneity 3 1.Introduction Ž . Ž . Pb Zr,Ti O PZT is one of the mostly x 1yx 3 widespread piezoelectric materials, due to their ap- plications in bulk or in thin film form. As thin film it Ž . is used forsurfaceacousticwaves SAW delay lines, ferroelectric field-effect transducers, radiation-hard nonvolatile random access memory Ž . w x NVRAM , pyroelectric sensors, etc. 1–3 . Different ) Corresponding author. Tel.: q39-0649934050; Fax: q39- 0620660061; E-mail: verardi@idac.rm.cnr.it techniques were used for the deposition of thin films: dc magnetron sputtering of multielement metal target wx wx in oxygen 2 , hydrothermal synthesis4 , sol–gel wx 5 , metal–organicchemicalvapor deposition Ž . wx MOCVD 6 , etc.More recently Pulsed Laser De- Ž . w x positionPLD , simple3,7 or direct-current glow wx discharge assisted 8 , was used to obtain high-qual- ity thin films. The atomic concentration of the ele- ments in the film and their positions in the ABO 3 internal structure was found to be of crucialinflu- ence on the piezoelectric properties of the deposited Ž . layers. Very few and not detailedresults concern- 0169-4332r99r$ - see front matter q 1999 Published by Elsivier Science B.V. All rights reserved. Ž . PII: S 0 1 6 9 - 4 3 3 2 9 8 0 0 5 7 7 - 7