Growth and measurements of ferroelectric lead zirconate titanate on diamond by pulsed laser deposition

Abstract

Pb(Zr 0.53 Ti 0.47 )O 3 (PZT) on diamond is a potentially robust structure for surface acoustic wave (SAW) device applications. We have studied the growth and physical characteristics of PZT on diamond and other substrates by pulsed laser deposition. Under a broad range of processing conditions we explored, PZT deposited directly on diamond is almost exclusively pyrochlore-type, which is nonferroelectric. Growth of ferroelectric perovskite PZT is promoted via the use of a PbTiO3 buffer layer within a narrow window of processing parameters [i.e., P(O2)=100–200 mTorr, T=550–650 °C, 1–2 J/cm2]. Similar results were also obtained for deposition of PZT on Si, Pt-coated Si, and Pt-coated diamond substrates. The dielectric constants of the perovskite PZT films are 500–650 at 1 V and 100 kHz. The piezoelectric coefficients of these films are in the range of 50×10−12–350×10−12 m/V. The SAW velocity of perovskite PZT films is similar to that of highly oriented sputter deposited ZnO films. The acoustic attenuation in perovskite PZT films is approximately three times higher than that in ZnO, however.