Search

Temperature dependent current-voltage (I-V) measurements of Au/Polyvinyl Alcohol + [Bi.sub.2][O.sub.3]/n-Si structure were conducted between 100 and 350 K for investigating the temperature dependence of I-V characteristics and current conduction mechanisms in the structure. Series resistance of the structure is calculated using Ohm's law and Cheungs' method. Ideality factor (n) and zero-bias barrier height ([Φ.sub.Bo]) were obtained considering thermionic emission theory. From 100 to 350 K, n changed from 32.1 to 3.54, and [Φ.sub.Bo] changed from 0.27 to 0.99 eV. Obtained temperature dependent values of n and [Φ.sub.Bo] suggested that thermionic emission is not the dominant current conduction mechanism. Therefore, Ln(I)-Ln(V) curves of the studied structure were plotted for investigating current conduction mechanisms in the structure and current flow is explained considering space charge limited current. Moreover, density of interface states ([D.sub.it]) in the structure were calculated and its temperature dependence was investigated such that [D.sub.it] values are reduced to the order of ~[10.sup.13] [eV.sup.-1] [cm.sup.-2] from ~[10.sup.14] [eV.sup.-1] [cm.sup.-2] with increasing temperature., INTRODUCTION Over the last decade, various types of metal-insulator-semiconductor (MIS) structures have been investigated vastly by many researchers [1-11]. Metal-polymer-semiconductor (MPS) structures are used as an alternative to conventional MIS [...]

Dielectric properties of 0.945([Bi.sub.0.5][Na.sub.0.5])Ti[O.sub.3]-0.055BaTi[O.sub.3] (BNBT5.5) ceramics are analyzed. The studies have shown that BNBT5.5 is a relaxor with a characteristic relaxation time that follows Vogel-Fulcher's law and the Vogel-Fulcher parameters of the relaxation time are calculated.

(1-x)([Bi.sub.0.9][La.sub.0.1])Fe[O.sub.3-x]PbTi[O.sub.3] (BLF-PT) crystalline solutions are prepared by the solid-state reaction method. The impedance spectroscopy study has shown that the high temperature conduction of BLF-PT is attributed to the motion of oxygen vacancies within the material and it is a promising candidate for high temperature applications.

Mn-doped [Bi.sub.4][Ti.sub.3][O.sub.12] (M-[B.sub.4][T.sub.3]) films are formed on a TiN/Si[O.sub.2]/Si substrate without buckling by using radio frequency (RF) magnetron sputtering. The M-[B.sub.4][T.sub.3] thin grown on a TiN/Si[O.sub.2]/Si substrate is shown to be a good candidate material for high performance, radio frequency metal-insulator-metal capacitors.

The growth of BiFe[O.sub.3] is demonstrated on many oxide and wide bandgap semiconductor substrates by using reactive molecular beam epitaxy in an adsorption-controlled growth regime. The epitaxial integration of the ferroelectric with the highest polarization, BiFe[O.sub.3], with high bandgap semiconductors is an vital step toward novel field-effect devices.

The relationship between phases and the electrical properties of bismuth perovskite ([Bi.sub.1/2][Na.sub.1/2])Ti[O.sub.3] (BNT)- and ([Bi.sub.1/2][K.sub.1/2])Ti[O.sub.3] (BKT)-based lead-free ferroelectric ceramics is studied. BKT ceramics are prepared by the hot-pressing (HP) method and BKT ceramics doped with a small amount of Bi have shown a relatively high remanent polarization and high piezoelectric properties.

Piezoresponse force microscopy (PFM) is used for examining the domain structure of multiferroic BiFe[O.sub.3]-PbTi[O.sub.3] single crystals with morphotropic phase boundary (MPB) compositions. The analysis of the complex PFM patterns obtained from the design setup has disclosed the presence of the rhombohedral, tetragonal, and orthorhombic domains, which is characteristic of the phase behavior of the MPB compositions.

Solid state processing methods are used for obtaining lead-free piezoelectric ceramics based on xBi([Zn.sub.1/2][Ti.sub.1/2])[O.sub.3]-(1-x)([Bi.sub.1/2][K.sub.1/2])Ti[O.sub.3] perovskite solid solutions. The dielectric and piezoelectric properties are improved with the addition of Bi([Zn.sub.1/2][Ti.sub.1/2])[O.sub.3] (BZT).