Volume 87, Issue 7, 01 April 2000
Index of content:
- DIELECTRICS AND FERROELECTRICITY (PACS 77)
Characterization of ferroelectricity in metal/ferroelectric/insulator/semiconductor structure by pulsed C–V measurement; Ferroelectricity in structure87(2000); http://dx.doi.org/10.1063/1.372364View Description Hide Description
Ferroelectric properties of the metal/ferroelectric/insulator/semiconductor (MFIS) structure were investigated using the structure. The ferroelectric hysteresis was observed for not only the capacitor but also the capacitor. The polarization evaluated by conventional C–V measurement should include interfacial polarization and rearrangement of the space charge together with the spontaneous polarization by ferroelectricity. To eliminate the generation of the interfacial polarization and the rearrangement of the space charge, the shorter charging time should be used to evaluate the ferroelectricity of the MFIS capacitor. Therefore, we propose the pulsed C–V measurement as a new method for evaluating the MF(I)S capacitor.
87(2000); http://dx.doi.org/10.1063/1.372365View Description Hide Description
Amorphous on single crystal has been crystallized by or ions with energy of 200 keV–2 MeV at a substrate temperature of 100–250 °C. Rutherford backscattering spectrometry in channeling geometry and x-ray diffraction were used to evaluate the crystallization. Ion-beam-induced epitaxialcrystallization (IBIEC) of was confirmed and the activation energy of IBIEC observed was about 0.1–0.3 eV, a value about 1/10 relative to thermal solid phase epitaxialcrystallization. The observed IBIEC seems to be consistent with previously proposed models in which IBIEC is dominated by point defects produced by ion irradiation and their migration to the amorphous/crystal interface. The IBIEC mechanism and point defect behavior are discussed by the use of simple models taking into account the rate limiting processes of IBIEC for both point defectdiffusion and atomic rearrangement at interface.
Quantitative study on the nonlinear piezoelectric effect in single crystals for a highly efficient surface acoustic wave elastic convolver87(2000); http://dx.doi.org/10.1063/1.372366View Description Hide Description
In this article we describe quantitative studies on the nonlinear piezoelectric effect in single crystals for a highly efficient surface acoustic waveelastic convolver. First, we demonstrate that a simple measurement of the nonlinear piezoelectric constant of is very effective for quantitative estimation of the efficiency of an elastic convolver. Next, the third-order piezoelectric constants, and in rotated Y-cut substrates are measured by varying the velocity under an applied electric field. Using the third-order piezoelectric constantsmeasured, quantitative estimations of the convolution efficiency are discussed.
87(2000); http://dx.doi.org/10.1063/1.372367View Description Hide Description
High resolution transmission electron microscopy is used to image the nanostructure of ultrafine ferroelectric lead titanate particles ranging from 20 to 2000 nm in diameter. The crystal structure,surface morphology, domain–wall structure, as well as surface reconstruction under a 400 KeV electron beam are studied. High resolution images and selected area diffraction patterns showed that all the particles had tetragonal structure; the ratio and domain size both decreased with decreasing particle size and the particles became monodomain when their diameter was less than 20 nm. A domain wall width of 14 Å was deduced from strain contrast shown by 90° domain walls. There is no evidence of amorphous surface layers; however surface reconstruction of lead titanate particles under the electron beam irradiation may produce small particles identified as face-centred PbO. The relationship between the physical properties and the observed nanostructures is discussed.