A wafer bending method has been devised to impose biaxial strains on Pb(Zr0.35Ti0.65)O3 (PZT) thin films ranging in thickness from 700 to 4000 Å grown by metal-organic chemical vapor deposition. The ferroelectric and dielectric properties of PZT capacitors were investigated while the film was placed under biaxial tension. It was observed that biaxial strains as small as 0.08% can reversibly reduce the remanent polarization of PZT films by 12 to 14% for all film thicknesses. The small-signal capacitance measured at voltages significantly larger than the switching voltage increased with increasing biaxial tension. These observations present clear evidence of room temperature strain accommodation in PZT thin films by reversible 90° domain wall motion that changes the volume fraction of the film that switches during electrical testing.

The structural and electrical properties of metalorganic chemical vapor deposition-grown Pb(Zr0.35Ti0.65)O3 thin films ranging in thickness from 700 to 4000 Å have been investigated. Cross-sectional scanning electron microscopy showed that these films are columnar, with grains extending through the thickness of the film. High-resolution x-ray diffraction showed that while the thickest films are tetragonal, with reflections corresponding to a-type and c-type domains, films thinner than 1500 Å are not. Electron backscatter diffraction and hysteresis loop measurements showed that the thinnest films are ferroelectric and have a rhombohedral crystal structure.

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Polarization fatigue in Pb Zr 0.45 Ti 0.55 O 3 -based capacitors studied from high resolution synchrotron x-ray diffraction J. Appl. Phys. 97, 064108 (2005); 10.1063/1.1870098 Comparison of crystal structure and electrical properties of tetragonal and rhombohedral Pb(Zr,Ti)O 3 films prepared at low temperature by pulsed-metalorganic chemical vapor deposition J. Appl. Phys. 92, 5448 (2002); 10.1063/1.1510169 Spatial variation of ferroelectric properties in Pb(Zr 0.3 ,Ti 0.7 )O 3 thin films studied by atomic force microscopyThe structural and electrical properties of Pb(Zr 0.35 Ti 0.65 )O 3 ͑PZT͒ thin films ranging in thickness from 700 to 4000 Å have been investigated. These ͑001͒/͑100͒-textured films were grown by metalorganic chemical vapor deposition on ͑111͒-textured Ir bottom electrodes. It was observed that, in the as-deposited state, the thinnest PZT films are rhombohedral even though bulk PZT of this composition should be tetragonal. Thicker films have a layered structure with tetragonal PZT at the surface and rhombohedral PZT at the bottom electrode interface. In this article we investigate the origin of this structure and its effect of the ferroelectric and dielectric properties of PZT capacitors. It has been suggested that thin films stresses can affect the phase stability regions of single domain PZT. This possibility has been investigated by piezoresponse microscopy and thin film stress measurements. In the as-deposited state the majority of PZT grains contain a single ferroelastic domain, whereas after a high temperature anneal, a large fraction of the grains contain several ferroelastic domains. Wafer curvature measurements in combination with x-ray diffraction stress measurements in the Ir bottom electrode showed that the as-deposited PZT films are, within experimental error, stress free at room temperature. Landau-Ginbzurg-Devonshire formalism was used to explain the origin of the rhombohedral phase as a result of substrate constraint on single domain PZT grains. Annealing was found to affect the relative volume fractions of the rhombohedral and tetragonal phases and the electrical properties of PZT films. Intermediate temperature anneals increased the volume fraction of the rhombohedral phase and the coercive field extracted from the polarization-electric field hysteresis loops. After a high temperature anneal ͑650°C͒ the majority of the grains transformed into a polydomain state, decreasing the volume fraction of the rhombohedral phase and the coercive field. If the high temperature anneal was performed after deposition of the top electrode, the coercive field became independent of the PZT thickness.

III-V semiconductors have emerged as the leading candidate to replace Si as the n-FET channel material for future low power logic applications. However, to realize the full performance benefits of III-V channels, it is crucial that external parasitic resistance (R ext ) be minimized. Among the different components of R ext , contact resistance (R C ), between metal and source/drain (S/D) junctions, has become the critical focus. Historically, multi-layered Au-based contacts (e.g. Au/Ge/III-V) are used in III-V processing to lower R C .However, the renewed interest in III-V semiconductors has attracted an increasing interest in developing Au-free contacts to III-V with low R C . In addition, a "silicide-like" metal contact process for III-V was recently developed by reacting Ni with InGaAs to form Ni-InGaAs. This is significant as it enables self-alignment and offers the option of using a common