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The effects of pressure and temperature on the conformational equilibrium of diethyl disulfide in various organic solvents were studied by Raman spectroscopy. From the pressure and temperature depe...

Barium titanate ceramics doped with yttrium as well as silica and alumina have been studied with special reference to the effects of the yttrium content. An yttrium content at which the ceramics showed a minimum resistivity increased with the increase of the sintering temperature and the added amounts of SiO2Al2O3. The microstructural studies with the electron probe X-ray microanalyzer revealed that these results should be explained in terms of the grain growth inhibitor effects of yttrium and the segregation of it to grain boundaries.

Since a green sheet of PZT ceramics is nowdays tapecast on a polymer film with comparative facility by using the so-called doctor-blade method, a capacitor and an actuator are produced for trial, having appropriate internal electrodes within, and their beneficial effects are stated with great emphasis. The effects of internal electrodes should be ascertained, as a rule, first, by investigating the functional characters of the device and, then, by analysing the computer simulation. Each sheet of a multilayer piezoelectric transformer fabricated as the subject of this paper has patterns of internal electrodes contrived in order to avoid delamination, and, in addition, the functional characters due to internal electrodes are made clear in this paper. From a practical standpoint, output voltage and current are, especially, expected and examined.

Effects of traps on the memory characteristics of ferroelectric field effect transistors with the metat-ferroelectric-insulator-semiconductor structure were theoretically analyzed. Various modes of operation, i.e. the polarization-limited mode, trap-limited mode, critical field-limited mode, MNOS mode and probability-limited mode, were derived depending on the device parameters. Experimental devices with gate insulator BaTiO3 or PLZT were fabricated by using thin film SnO2 and thin film Te. The memory characteristics of these devices were interpreted in terms of the trap-limited mode and MNOS mode, respectively.

Ferroelectric PZT films were successfully fabricated by reactive magnetron sputtering using a composit metal target. The films often showed asymmetric hysteresis loops which were brought about by a spontaneous internal biasing field. The field also affected stability of the poled film during application of a high ac voltage. In some cases, films without poling treatment showed evident pyroelectric response.

The paper describes a loop tracer for observing hysteresis phenomena in ferroelectrics; the tracer utilizes recent digital technology and can record the hysteresis phenomena instantaneously. As the operation speed is very fast, it is easy to observe the loop of aged specimens without changing their electrical state, as well as to trace the depolarizing process dynamically when an ac voltage is applied. From the data obtained a new representation for ferroelectric hysteresis curve has been proposed and discussed with special reference to determination of an internal bias field in the materials.