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Highly [100]-oriented Pb(Zr, Ti)O3 (PZT) films were prepared on (100) GaAs and (100) Si substrates with MgO buffer layer by pulsed laser ablation (PLA). The depth profile of the constituent elements observed by X-ray photoelectron spectroscopy (XPS) shows that there are no remarkable interdiffusion and/or no formation of an alloying layer at both interfaces between PZT and MgO and between MgO and GaAs substrate. The [100]-oriented perovskite PZT films which exhibit the ferroelectric hysteresis loop were obtained on (100) Si substrate with MgO buffer layer with the thickness of only 50 Å, showing that this technique promises the realization of metal-ferroelectric-semiconductor field-effect transistors (MFS-FETs).

(Ba x Sr1- x )TiO3 (x=0-1.0) (BST) thin films were prepared on (111)Pt/Ti/SiO2/Si substrates by pulsed laser ablation (PLA) using an ArF excimer laser at various oxygen pressures. The film compositions agree well with those of the targets. For all the film compositions, the crystalline structure of the thin films is a single perovskite phase. The thin films prepared at 133 Pa are randomly oriented. The films preferentially oriented along the [111] direction are obtained at low oxygen pressures (6.67 and 13.3 Pa). The surface morphology of the thin films becomes rougher with increasing oxygen pressure. Moreover, this roughening is prominent with low Ba content. The excessively high oxygen pressure during PLA deposition deteriorates the crystal structure and the dielectric property of BST films. The dielectric constant of BST (x=0.6) thin film prepared at the oxygen pressure of 6.67 Pa is 800 at 1 MHz.

Ferroelectric lead-zirconate-titanate (Pb(Zr0.52Ti0.48)O3: PZT) thin-film capacitors were fabricated by pulsed laser ablation using Ni-alloy electrodes on oxidized (100) silicon. Polarization fatigue after a large number of switchings was investigated with a variety of frequencies. The frequencies for acceleration of fatigue and for measurement of the switched charge density Q sw were varied simultaneously or independently. The fatigue test revealed that the increase in the frequency both for acceleration and measurement of switching pulse increases the life of polarization reversal while it decreases Q sw. At 50 kHz, Q sw keeps the initial value even after switching above 1010 cycles. The measurement frequency dependence of Q sw suggests that a homogeneous fatigue takes place irrespective of fast and slow domains and additional layers of a low dielectric constant are probably formed in the ferroelectric-metal interface.

Titanium-aluminum-nitride (Ti–Al–N; TAN) electrode films were prepared by pulsed laser ablation on (100)Si and (100)MgO substrates for ferroelectric lead-zirconate-titanate ( Pb(Zr0.52Ti0.48)O3; PZT) thin-film capacitors. Capacitors with rather randomly oriented PZT films on the TAN/(100)Si did not show a ferroelectric hysteresis loop, but the capacitor with preferentially [100]-oriented PZT film on the TAN/(100)MgO did. This suggests that a TAN-electrode film was grown on (100)MgO with a high oxidation resistance at the high temperature employed for ferroelectric oxide preparation.