Reactive ion etching damage to Pt/Pb(Zr, Ti)O3/Pt ferroelectric capacitors was evaluated under Ar bombardment and CHClFCF3 etch plasmas. The hysteresis and degradation properties, including fatigue and leakage current, were examined systematically to study the mechanism of damage. The damage was measured quantitatively by comparing the relative voltage shift with respect to the initial hysteresis loops. The damage effects were found to be dependent on etching time and mainly due to the physical effect of ion bombardment. The electrical properties of the etched Pt/Pb(Zr, Ti)O3/Pt capacitors were substantially recovered by annealing at 400 °C for 30 min.

As an optical material, Y2O3 transparent ceramics are desirable for application as laser host materials. However, it is difficult to sinter and dense of Y2O3 hinders the preparation of high-quality optical ceramics via traditional processes. In this work, we use La2O3 as a sintering aid for fabricating high-transparency Y2O3 ceramics using a vacuum sintering process. It is demonstrated that the in-line optical transmittance of 15.0 at% La-doped Y2O3 at a wavelength of 1100 nm achieves a transmittance of 81.2%. A sintering kinetics analysis reveals that a grain-boundary-diffusion-controlled mechanism dominates the faster densification at high La3+ concentrations. It is also shown that both the mechanical and thermal properties of Y2O3 transparent ceramics are significantly improved upon the increase of La2O3 sintering additives. The results indicate that a La-doped Y2O3 transparent ceramic is a promising candidate for a laser host material.

One of the key processing concerns in the integration of PbZrxTi1−xO3false(PZTfalse) thin film capacitors into the existing VLSI for ferroelectric or dynamic random access memory applications is the patterning of these films and the electrodes. In this work, we have identified a suitable etch gas false(CCl2F2false) for dry etching of PZT thin films on RuO2 electrodes. The etch rate and anisotropy have been studied as a function of etching conditions. The trends in the effect on the etch rate of the gas pressure, RF power and O2 additions to the etch gas have been determined and an etching mechanism has been proposed. It was found that ion bombardment effects are primarily responsible for the etching of both PZT and RuO2 thin films. Etch rates of the order of 20–30 nm/min were obtained for PZT thin films under low gas pressure and high RF power conditions. The etch residues and the relative etch rates of the components of the PZT solid solution were determined using XPS. The results show that the etching of normalPbO is the limiting factor in the etch process.

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A new process for the reactive ion etching (RIE) of both PbZri-^T^Os (PZT) thin films and RuO2 electrodes is presented, employing etching gases with low ozone depletion potential (ODP) and global warming potential (GWP). The etching process has been investigated as a function of etching time, discharge power density, chamber pressure, and additive gas. Etch rates were in the range of 250-650 A/min and 100-400 A/min for PZT and RuO2, respectively. A large etch selectivity between PZT and RuO2 was optimized. Etched surfaces exhibited smooth morphologies. Furthermore, the ferroelectric properties of PZT were not altered significantly by the etching process. A surface residue containing Cl and F was found after etching, but this organic substance was totally removed by an after-etch bake. In addition, the etched profile of the PZT films was studied through SEM.