Inversion of the impurity conductivity sign in As2Se3:Bi films deposited by two different methods (original) (raw)
Related papers
Electrical properties of Bi-implanted amorphous chalcogenide films
Thin Solid Films, 2015
The impact of Bi implantation on the conductivity and the thermopower of amorphous chalcogenide films is investigated. Incorporation of Bi in Ge-Sb-Te and GeTe results in enhanced conductivity. The negative Seebeck coefficient confirms onset of the electron conductivity in GeTe implanted with Bi at a dose of 2x10 16 cm -2 . The enhanced conductivity is accompanied by defect accumulation in the films upon implantation as is inferred by using analysis of the space-charge limited current. The results indicate that native coordination defects in lone-pair semiconductors can be deactivated by means of ion implantation, and higher conductivity of the films stems from additional electrically active defects created by implantation of bismuth.
Space charge limited conduction in a-Bi 0.5 Se 99.5− x Zn x films
Journal of Materials Science Letters, 2003
Chalcogenide glasses have attracted much attention because of their potential application in solid state devices. Impurity effects in chalcogenide glasses may have importance in fabricating glassy semiconductors. Moreover they are interesting as core materials for ...
IV measurements of chalcogenide glass thin films
Indian Journal of Pure …, 2006
Measurements of I-V characteristics of Se 85-x Te 15 Sb x (where x = 2, 4, 6, 8 and 10) glassy thin films have been carried out at ambient conditions. These measurements have been taken using Keithley Electrometer/High Resistance Meter 6517A in its force voltage measure current (FVMI) mode. Measurements show that the film containing 4 at. wt. % of Sb allows the maximum current to pass through itself as compared to other counterparts of this series. The composition dependence of resistance has been explained on the basis of bond formation between Se and Sb at different compositions and hence Se 81 Te 15 Sb 4 composition could be termed as "critical composition" in the series under test as it is also strongly supported by dc electrical conductivity, thermal conductivity and thermal diffusivity measurements of these materials in bulk. Besides, the linear relationship between ln (I) and V 1/2 confirm the conduction mechanism as to be Poole-Frenkel type.
Optical and electrical studies of as-prepared and annealed Se-Te-Bi thin films
Applied Physics A-materials Science & Processing, 2008
The effect of thermal annealing on the electrical and optical properties of a thin film of Se-Te-Bi alloy has been studied. It has been found that the mechanism of optical absorption follows a non-direct transition. The optical band-gap decreases with an increase in the Bismuth concentration. The electrical conductivity of the as-deposited and annealed films has been found to be of Arrhenius type. The results are discussed on the basis of rearrangements of defects and disorders in the chalcogenide systems.
Journal of Ovonic Research, 2019
Glassy alloy of In 3 Te 7 Bi x Se 90-x (x = 0,5,10,15) are prepared by melt-quenching technique.Thin filmsare deposited by the thermal evaporation technique on glass substrates under a pressure of 10-6 torr. The structural analyses of these films were carried out by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Scattering (EDS).X-ray diffraction (XRD) of thin films was carried out to analyze the amorphous or polycrystalline behavior of the thin films. EDS analysis shows the presence of the compositional elements in the thin films.SEM shows the surface morphology of the thin films and development of grains. Optical studies were carried out by the Ultra violet visible (UV-Vis)Sperctoscopy in the range of 190-1100 nm.The analysis of optical absorption spectra shows indirect optical band gap. The optical band gap decreases with increasing Bismuth concentration from 1.38 eV to 1.02 eV. The DC conductivity was carried out in specially designed metallic sample holder with vacuum 10-4 Torr.The DC conductivity of thin films of In 3 Te 7 Bi x Se 90-x increases and the corresponding activation energy decreases with increasing of bismuth content which may be due to shift in Fermi level.
Chemical deposition and characterization of glassy bismuth(III) selenide thin films
Thin Solid Films, 2002
Glassy thin films of bismuth(III) selenide were deposited onto glass and polyester substrates using a chemical bath deposition technique. X-Ray diffraction analysis was used for identification of the material obtained. Optical and electrical properties of the films were investigated. According to the resistance-temperature measurements, Bi Se thin films are typical semi-conducting 2 3 materials with calculated activation energies of 0.2 and 1.1 eV for lower and higher temperatures, respectively, and the majority charge carriers are electrons. As-deposited films are characterized with band gap energy of 2.3 eV, which does not exhibit significant changes upon annealing.
Electrical and photoelectrical properties of glassy As2Se3 doped with Mn, Dy and Sm
1996
The chalcogenide glassy semiconductor As2Se3 doped with Mn, Dy and Sm presents practical interest for optoelectronic devices. Doping by metals influences electrical conductivity and photoelectric characteristics. The conductivity is significantly increased by addition of Mn and Dy impurities. All the dopants hamper the photoconductivity with exception of 0.5 at.% Dy, which generates a broad impurity band in the photoconductivity spectrum near 1.05 eV, ascribed to the presence of a small amount of finely dispersed crystalline phase
6. Conductivity effects in amorphous chalcogenide films
Vacuum, 1978
Thin amorphous films of chalcogenide Te 48-A~,8-Ge6-Si28 were prepared and their current-voltage (l-V) characteristics were examined. Memory switching effects were observed which were stable and reproducible, but the switching voltage was found to depend on the restoring voltage in a regular way for cyclic switching. Furthermore, the time delay for an applied voltage pulse to cause switching may be related to the I-V curve prior the switching. This dependence seems to support an electronic mechanism of switching.
Journal of information and communication convergence engineering, 2011
The absence of deep traps for electrons in the spectrum of As 40 Se 30 S 30 localized states films obtained by ion sputtering was determined. Bipolar drift of charge carriers was found in amorphous As 40 Se 30 S 30 films of chalcogenide glassy semiconductors, obtained by ion-plasma sputtering of high-frequency, unlike the films of these materials obtained by thermal evaporation.