The infrared reflectance spectra of lithium borate glasses (0–73 mol% Li 2 O) have been measured over a broad and continuous spectral range (30–4000 cm −1 ) in an attempt to study systematically their structure. The reflectance data have been analyzed by Kramers-Kronig inversion to obtain the optical and dielectric properties of the materials. The study of the deconvoluted mid-infrared spectra has revealed a glass network built up of various boron-oxygen groups, with structure and concentration strongly dependent on the Li 2 O content. Of particular interest was the far-infrared asymmetric absorption profile, which could be well simulated by two broad bands attributed to vibrations of lithium cations in two distinct network environments. The presence of these two Li + -host site distributions was found to be independent of the details of the borate network structure and has been taken to imply a more general characteristics of ionic conducting oxide glasses.

Infrared reflectance spectra of lithium borate glasses

https://escholarship.org/content/qt6p3188fd/qt6p3188fd.pdf?t=p0him6

Electrochromic materials and devices for energy-efficient windows

Gives a critical review of idealised two-phase geometrical models. These treatments derive expressions for the resistivity and Hall coefficient of a composite material in terms of the properties of its constituents. The authors show that these models can be applied to the interpretation of transport measurements in polycrystalline films and powder layers. Important distinctions are made depending on whether the depletion layers extend completely or partially through the grains, whether the Debye length is greater or less than the grain size and whether the mean free path is greater or less than the grain size. The authors discuss the theoretical treatment of the Hall effect in percolative systems, as geometrical models neglect percolation. The modulation of Hall coefficient and conductivity by illumination and the adsorption and desorption of ambient gases are also considered.

https://iopscience.iop.org/article/10.1088/0034-4885/43/11/001/pdf

The Hall effect in polycrystalline and powdered semiconductors

Borate glasses are the technologically important class of glasses and play a significant role in various applications. Borate glasses contain planar BO3 groups as structural units, rather than tetrahedral SiO4 groups. The oxygen atoms are, as in SiO2, again connected to two network-forming atoms, in case of boron. The radial distribution analysis describes the B2O3 glass structure as consisting of boroxol rings, that is, planar rings containing three boron atoms and three oxygen atoms. The network forming of the B2O3 and the SiO4 is affected with the addition of some metal cation additives Pb, Zn, Cd, and so forth. These additives also work as a network modifier and a nucleating agent for crystallization of glass. Therefore, the optical properties of the borate glasses have been changed significantly.

https://downloads.hindawi.com/archive/2012/428497.pdf

A Review on Infrared Spectroscopy of Borate Glasses with Effects of Different Additives

An active layer of an NTFT includes a channel forming region, at least a first impurity region, at least a second impurity region and at least a third impurity region therein. Concentrations of an impurity in each of the first, second and third impurity regions increase as distances from the channel forming region become longer. The first impurity region is formed to be overlapped with a side wall. A gate overlapping structure can be realized with the side wall functioning as an electrode.

Semiconductor device and manufacturing method therefor

Scintillation characteristics of the Czochralski‐grown ZnWO4 single crystal were studied. This crystal, with light red‐brown color, exhibits a maximum luminescence wavelength of 480 nm under excitation at 254 nm. The total luminescence output under x‐ray excitation at 254 nm. The total luminescence output under x‐ray excitation was found to be 2.3 times larger than that of the best Bi4Ge3O12 at room temperature with small afterglow.

Scintillation study of ZnWO4 single crystals

The ionic conductivity of evaporated Li2OB2O3 thin films has been studied. These thin films were found to show a considerably high ionic conductivity of 1 × 10−7 Ω−1 cm−1 at room temperature. The conductivity increases with increasing Li content and exhibits a maximum value near 3Li2O·B2O3. The structure of these films was determined using infrared absorption and laser Raman scattering spectroscopy. Using the results, the correlation between structure and conductivity is also discussed.

Ionic conductivity of Li2OB2O3 thin films

A thin, amorphous LiAlF4 film, with lithium ion conductivity of 1×10−4 S/m at 25 °C, has been prepared by vacuum evaporation. Utilizing this thin film as a solid electrolyte, an ITO/WO3/LiAlF4/LiIn overlayer has been constructed (ITO: indium‐tin‐oxide). For it, the electrochromism of WO3 due to lithium ion injection was observed.

Electrochromism of WO3/LiAlF4/LiIn thin‐film overlayers

Amorphous thin film ionic conductors of mLiF.nAlF3

A method for laser zone melting and apparatuses therefor wherein, in a zone melting method for a thin film due to the irradiation of laser beam, the laser beam is vibrated at the frequency of more than 1 Hz in the direction substantially perpendicular to the moving direction of a melting zone and the fluctuation of laser beam output is controlled to less than 1%. The zone-melted thin films manufactured by this method have good electrical properties resulting from less crystal imperfection, less non-stoichiometric excess atoms of the constituents, and less thickness corrugation of the film due to the suppression of temperature fluctuations and its spacial inhomogeneity at the time of zone melting.

Tetsu Oi

Papers

Scintillation study of ZnWO4 single crystals

Ionic conductivity of Li2OB2O3 thin films

Electrochromism of WO3/LiAlF4/LiIn thin‐film overlayers

Amorphous thin film ionic conductors of mLiF.nAlF3

Method and apparatus for laser zone melting