In situ growth of SrBi 2 Ta 2 O 9 (SBT) films as a function of Bi concentration in the target, substrate temperature, oxygen pressure, and the thickness of bottom Pt electrode by pulsed laser deposition was studied. The SBT phase initially formed at a temperature of 500 -520 ± C. The SBT films grown from the stoichiometric target generally showed Bi deficiency. A well-crystallized and stoichiometric SBT film could be grown at a temperature of 550-580 ± C in 300 mTorr of O 2 from the surplus Bi targets, which showed c-axis preferred orientation. The formation temperature of SrTa 4 O 11 (ST) phase was above 600 ± C, depending on the Bi concentration in the target. Higher oxygen pressure raised the formation temperatures of the SBT and ST phases and concomitantly enriched the Bi concentration of the SBT films. For the bottom Pt electrode 1200Å thick, the voids were not observed in the SBT overlayer until the deposition temperatures were above 590 ± C. Annealing at temperatures above 700 ± C in an atmosphere of O 2 was required to improve the contact between Pt electrode and the SBT film and hence the ferroelectric properties of the SBT film. In the present study, a smooth, stoichiometric, and c-axis oriented SBT film, about 350 nm thick, could be grown on Pt (1200Å)͞Ti͞SiO 2 ͞Si at a temperature of 550-580 ± C in 300 mTorr of O 2 from the Bi surplus targets, which showed remnant polarization (P r ) of 3.0-3.5 mC͞cm 2 and coercive field (E c ) of 30-40 kV/cm at 4 V. No fatigue was observed up to 10 9 switching cycles.

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The interfacial reactions of Pd/Si0.76Ge0.24 were studied by pulsed KrF laser annealing as a function of energy density and pulse number. At an energy density of 0.1–0.4 J/cm2, a continuous germanosilicide layer composed of a low-temperature phase, Pd2(Si1−xGex), and a high-temperature phase, Pd(Si1−xGex), was formed. In contrast to vacuum annealing, Ge segregation out of the germanosilicide layer and the strain relaxation of the residual Si0.76Ge0.24 film could be effectively suppressed by pulsed KrF laser annealing at 0.1 J/cm2. Multiple pulse annealing at 0.1 J/cm2 could further homogenize the Pd concentration of the germanosilicide layer and promote the growth of Pd(Si1−xGex). Concurrently, the smoothness of the germanosilicide layer was substantially improved in comparison with those grown by vacuum annealing at temperatures above 200 °C. The studies also revealed that for multiple pulse annealing at 0.1 J/cm2 with a low repetition rate, 1 Hz, the evolution of phase formation and Pd diffusion could be proceeded by each individual laser pulse.

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