Fabrication and Properties of Metal-PZT-Metal Capacitors by Liquid Delivery Mocvd

Abstract

Pb(Zr 1−x ,Ti x )O 3 (PZT) thin films were prepared on 8-inch and 4-inch Pt or Ir-electroded Si wafers by liquid delivery metal-organic chemical vapor deposition (LD-MOCVD) using cocktail sources of Pb, Zr and Ti. The processing conditions were optimized in order to obtain high-performance PZT films. The thickness uniformity of PZT films on 8-inch substrate was about ±3.24%. The deposition rate of Pb (15.8 nm/min) and Ti (17.9 nm/min) deposited on Si substrate were faster than that of Zr (2.5 nm/min). The growth temperature of PZT film was adjusted to 570-630 • C depending on the substrates used. The properties of metal/PZT/metal capacitors were also studied. The PZT films based on Pt substrate showed no good ferroelectric properties. By contrast, the ferroelectric properties of Ir/IrO 2 /PZT/IrO 2 /Ir capacitors were excellent. At an applied voltage of 5 V, the remanent polarization (P r ) and coercive field (E c ) values were about 36 µC/cm 2 and 50 kV/cm, respectively.