Search results for "conductivity"
showing 10 items of 1988 documents
Correlated effects of fluorine and hydrogen in fluorinated tin oxide (FTO) transparent electrodes deposited by sputtering at room temperature
2021
The optical and electrical properties of fluorinated tin oxide (FTO) films deposited at room temperature by sputtering have been investigated varying the fluorine content and the hydrogen atmosphere. The complex behavior of the obtained films is disclosed using a wide set of characterization techniques that reveals the combined effects of these two parameters on the generated defects. These defects control the electrical transport (carrier density, mobility and conductivity), the optical properties (band gap and defects-related absorption and photoluminescence) and finally promote the amorphization of the samples. H2 in the sputtering gas does not modify the H content in the films but induc…
Hopping Conductivity in Hydrogen-Bonded Antiferroelectric Compounds
1991
Antiferroelectric betaine phosphate (BP: (CH3)3NCH2COO · H3PO4) and ferroelectric betaine phosphite (BPI: (CH3)3NCH2COO · H3PO3) are molecular crystals of the amino acid betaine and the phosphoric or phosphorous acids, respectively. In both compounds the inorganic components are linked by hydrogen bonds to one-dimensional chains. The two isostructural compounds form solid solutions BPxBPI1-x at any concentration. Here we report measurements of the dielectric permittivity for concentrations 0.85 ≤ × ≤ 1 at frequencies 10−2 ≤ v ≤ 109 Hz and temperatures 2 K ≤ T ≤ 300 K. The dielectric response in BP:BPI (x = 0.95) is dominated by contributions from pure hopping conductivity which we ascribe t…
Hydrogen-doped cubic diamond and the crystal structure of n-diamond
2011
To understand the crystal structure of n-diamond, a hydrogen-doped (H-doped) diamond model has been investigated using first principles calculations. In particular, hydrogen concentration dependent elastic constants and lattice parameters for the H-doped diamond have been analyzed. Our results indicate that when the hydrogen concentration is less than 19 at.%, the H-doped diamond is mechanically stable. When the hydrogen concentration is about 4 at.%, the optimized lattice parameter, simulated XRD pattern and electronic properties for the H-doped diamond all agree well with the corresponding experimental values of n-diamond. The results imply that the n-diamond is likely to be an H-doped di…
Electronically induced trapping of hydrogen by impurities in niobium
1984
The binding energies of hydrogen and its isotopes to substitutional impurities Ti, Cr, and V in niobium have been calculated. The hydrogen-metal interaction is based on the effective-medium theory. The wave mechanics of the hydrogenic interstitials are explicity dealt with, and the lattice distortion created by the hydrogen is incorporated through the method of lattice statics. The difference in the electronic structure between impurity and host atoms is shown to be largely responsible for the binding of hydrogen to the impurities. The results are in agreement with recent inelastic neutron scattering experiments. Peer reviewed
Plasma-Enhanced Atomic Layer Deposition of Silver Thin Films
2011
Thermal properties of various silver precursors known in the literature were evaluated in order to discover which precursor is the most suitable one for plasma-enhanced atomic layer deposition (PEALD) of silver thin films. Ag(fod)(PEt3) (fod = 2,2-dimethyl-6,6,7,7,8,8,8-heptafluorooctane-3,5-dionato) was found to be the best choice. Using Ag(fod)(PEt3) together with plasma-activated hydrogen, silver thin films were deposited at growth temperatures of 120–150 °C, and ALD-type saturative growth was achieved at 120–140 °C. At 120 °C, the growth rate was 0.03 nm per cycle. The plasma exposure time had also an effect on the growth rate: with shorter exposure times, the growth rate was lower over…
LABORATORY INSTRUMENTATION TO STUDY CHANGES OF ELECTRICAL CONDUCTIVITY OF ROCKS WITH CHANGES OF FREQUENCY, TEMPERATURE AND PRESSURE*
1983
A laboratory instrument was developed to investigate the electrical properties of rock samples with respect to changes of frequency, temperature and pressure. The instrument can be used to obtain general trends and typical values for geological media. It should be of particular interest in geothermal studies and research in the geophysical properties of rocks. The design intervals for quantities under investigation were 20–300°C, 10 5 -4 × 10 7 Pa and 5 × 10 −4 -10 3 Hz. Certain limitations exist on the simultaneous use of the highest values of temperature and pressure. The main features of the instrument are: analog electrical outputs recorded by an x-y recorder or observed on a scope with…
Permanent photodoping of plasmonic gallium-ZnO nanocrystals
2020
This work was supported by the Latvian Council of Science in the framework of FLPP (Plasmonic oxide quantum dots for energy saving smart windows, lzp-2018/1-0187). Tanel Käämbre acknowledges financial support for the XPS instrumentation maintenance from the Estonian Centre of Excellence in Research project “Advanced materials and high- technology devices for sustainable energetics, sensorics and nanoelectronics” (TK141).
Laser direct writing of gold conductors from metallorganic inks
1993
Laser deposition of gold lines from spin-on metallorganic (MO) precursors has been studied. A readily available and relatively low-cost commercial MO ink has been used to write gold interconnects on different substrates. The physical properties of the ink, its laser-firing process on oxidised silicon substrates and its electrical characterisation are presented here, together with the experimental procedure needed for obtaining low-resistivity deposits.
Preparation and conductivity of PEDOT encapsulated inside faujasites
2005
Poly[3,4-(ethylenedioxy)thiophene] (PEDOT) encapsulated inside the faujasite micropores has been prepared by polymerization of the monomer in partially Fe-exchanged faujasites. Faujasites containing PEDOT within the interior exhibit notable electrical conductivity compared to plain faujasite. This conductivity is attributed to the presence of polarons that have been detected by EPR spectroscopy.
Novel chemical reaction co-precipitation method for the synthesis of apatite-type lanthanum silicate as an electrolyte in SOFC
2017
Abstract Apatite-type lanthanum silicates have promising performance as electrolyte materials for IT-SOFC. A novel co-precipitation method, based on chemical reaction, is employed in the synthesis process. The reaction products: La(OH) 3 and SiO 2 are used as precursors of apatite synthesis process. The precursors are mixed in molecular scale which provide much conducive to formation reaction. The pure apatite phase composition is obtained with quite moderate temperature of 700 °C for 6 h which shows considerable ionic conductivity performance. The conductivity decreases when you increase the calcination temperature in according with XRD measurement. The XRD measurement shows the presence o…