Ferroelectric capacitors having Pt bottom and top electrodes and a ferroelectric film of composition PbZr0.51Ti0.49O3 (PZT) were fabricated and investigated. The PZT films of thicknesses varying from 0.12 to 0.69 μm were prepared by organometallic chemical-vapor deposition. Annealed capacitors were investigated by capacitance, hysteresis, and pulse switching measurements. It is found that the thickness dependence of the reciprocal capacitance, the coercive voltage, and the polarization measured by pulse switching can all be explained by a blocking layer model, in which a dielectric layer of thickness dbl and relative permittivity εbl is situated between the PZT film and an electrode. It is shown that (i) the coercive field is independent of thickness having a value of 2.4 V/μm; (ii) the ratio εbl/dbl is in the range 20–28 nm−1; (iii) the voltage across the blocking layer is proportional to the polarization, Vbl=cP, where c=4.1±0.5 V m2/C; and (iv) the polarization depends on the electric field in the PZT layer, independent of thickness. Pulse switching endurance measurements showed that in the saturation range the fatigue for these ferroelectric capacitors is determined by the pulse voltage and is independent of the thickness.

Little is known about Indigenous communities and dementia and Elders have not been involved as advisors or participants in most research to date. This exploratory research sought to address this gap through a constructivist grounded theory project on the views of First Nation Elders on memory loss and memory care in later life, conducted in collaboration with decision-makers from the local Health Authority and Elders from three First Nation communities in British Columbia, Canada. Elders served as advisors to this research and research agreements were negotiated and signed with each community. Data collection occurred through a series of sharing circles and interviews with a total of 21 Elders, four of whom were experiencing memory loss, and two community members. Four themes arose through the constant comparative data analysis process: Being Secwepemc, growing older, losing memory, and supporting one another. These themes indicate that memory loss and memory care in First Nation communities has changed over the past century, including the causes attributed to memory loss in later life and community responses to those affected. Elders hold differing views about memory loss, including the traditional--'going through the full circle' [of life]--and the shémá [white] way--'your dementia', with the latter being much more common. This research indicates the importance of protecting and reviving traditional knowledge and ways of life in order to prevent 'your dementia' and avoid the adoption of health care practices that may be culturally unsafe for First Nation Elders.

The current density is measured as a function of time for thin (⩽1000 Å) barium strontium titanate (BST) capacitors with platinum electrodes. The current density curve shows a peak prior to the onset of resistance degradation. The peak position on the time axis varies with applied voltage and temperature. The data are explained by the theory for space-charge-limited (SCL) current transients, and the measured current is identified as ionic current associated with oxygen vacancies. Using the SCL analysis, the mobility of the oxygen vacancies is measured as a function of temperature. The mobility obtained from current measurements is shown to be compatible with the Einstein relation for mobility and diffusivity. In summary, the ionic current associated with oxygen vacancies is shown to be an important component of the measured current in thin BST films.

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Structural and ferroelectric properties of the caxis oriented SrBi2Ta2O9 thin films deposited by the radio frequency magnetron sputtering