46 research outputs found

    Transport characteristics of Pd Schottky barrier diodes on epitaxial n-GaSb as determined from temperature dependent current-voltage measurements

    Get PDF
    Please read abstract in the article.SA Research Chairs Initiative of the Department of Science and Technology, National Research Foundation and the NMMU.http://www.elsevier.com/locate/tsfhb201

    dc-Hydrogen plasma induced defects in bulk n-Ge

    Get PDF
    Bulk antimony doped germanium (n-Ge) has been exposed to a dc-hydrogen plasma. Capacitance-voltage depth profiles revealed extensive near surface passivation of the shallow donors as evidenced by ˜ a 1.5 orders of magnitude reduction in the free carrier concentration up to depth of ˜ 3.2 µm. DLTS and Laplace-DLTS revealed a prominent electron trap 0.30 eV below the conduction (Ec-0.30 eV). The concentration of this trap increased with plasma exposure time. The depth profile for this defect suggested a uniform distribution up to 1.2 µm. Annealing studies show that this trap, attributed to a hydrogen-related complex, is stable up to 200 °C. Hole traps, or vacancy-antimony centers, common in this material after high energy particle irradiation, were not observed after plasma exposure, an indication that this process does not create Frenkel (V-I) pairs.The South African Research Chair’s Initiative of the Department of Science and Technology, National Research Foundation, as well as by the Nelson Mandela Metropolitan University (NMMU).http://www.elsevier.com/locate/phys

    Field dependence of the E1' and M3' electron traps in inductively coupled Ar plasma treated n-Gallium Arsenide

    Get PDF
    Inductively coupled Ar plasma etching of n-type (Si doped) Gallium Arsenide (GaAs) introduces several electron traps, Ec – 0.04 eV (labelled E10), Ec – 0.19 eV, Ec – 0.31 eV, Ec – 0.53 eV, and Ec – 0.61 eV (behaving like the well documented M3 and labelled M30 in this study), of which the metastable defects Ec – 0.04eV (E10 ), and Ec – 0.07 eV are novel. Furthermore, E10 and M30 exhibit strong field enhanced carrier emission. Double-correlation deep level transient spectroscopy was used to investigate the field dependent emission behaviour of these two defects. It is shown that for both traps, the observed enhanced emission is due to phonon assisted tunnelling. The latter observation is contrary to the literature reports suggesting that enhanced carrier emission for M3 occurs via the Poole-Frenkel mechanism.http://jap.aip.org/nf201

    Ar plasma induced deep levels in epitaxial n-GaAs

    Get PDF
    Ar plasma etching of n-type (Si doped) GaAs introduces several electron traps (Ec - 0.04 eV, Ec - 0.07 eV, Ec - 0.19 eV, Ec - 0.31 eV, Ec - 0.53 eV, and Ec - 0.61 eV). The trap, Ec - 0.04 eV, labelled E10 and having a trap signature similar to irradiation induced defect E1, appears to be metastable. Ec - 0.31 eV and Ec - 0.61 eV are metastable too and they are similar to the M3/M4 defect configuration present in hydrogen plasma exposed n-GaAs.South African National Research Foundationhttp://jap.aip.org/nf201

    Inductively coupled plasma induced deep levels in epitaxial n-GaAs

    Get PDF
    The electronic properties of defects introduced by low energy inductively coupled Ar plasma etching of n-type (Sidoped)GaAs were investigated by deep level transient spectroscopy (DLTS) and Laplace DLTS. Several prominent electron traps (Ec—0.046 eV, Ec—0.186 eV, Ec—0.314 eV. Ec—0.528 eV and Ec—0.605 eV) were detected.The metastable defect Ec—0.046eV having a trap signature similar to E1 is observed for the first time. Ec—0.314eV and Ec—0.605 eV are metastable and appear to be similar to the M3 and M4 defects present in dc H-plasma exposed GaAs.South African National Research Foundationhttp://www.elsevier.com/locate/physbnf201

    Being (im)polite: A forensic linguistic approach to interpreting a hate speech case

    Get PDF
    In a hate speech case a court might have to determine whether a person’s words were hurtful or harmful. Would it be possible to determine whether words are hurtful or harmful by using linguistics? This article offers a linguistic perspective on a court’s interpretation of the Equality Act in a hate speech case and focuses on speech acts and politeness. If the speech acts of a verbal exchange are studied and the levels of politeness are gauged, a court would be able to affi rm the hurtfulness or harmfulness of the speaker’s words. The article begins with a brief discussion on the potential role of the linguist in a courtroom; this is followed by a summary of the facts of the case. Then the court case is analysed and discussed in terms of speech acts and politeness. By employing principles in pragmatics the author reaches the same conclusion as the court.Afrikaans and Theory of Literatur

    The MeerKAT Galaxy Cluster Legacy Survey: I. Survey overview and highlights

    Get PDF
    Please abstract in the article.The South African Radio Astronomy Observatory (SARAO), the National Research Foundation (NRF), the National Radio Astronomy Observatory, US National Science Foundation, the South African Research Chairs Initiative of the DSI/NRF, the SARAO HCD programme, the South African Research Chairs Initiative of the Department of Science and Innovation.http://www.aanda.orghj2022Physic

    The SARAO MeerKAT 1.3 GHz Galactic Plane Survey

    Get PDF
    We present the SARAO MeerKAT Galactic Plane Survey (SMGPS), a 1.3 GHz continuum survey of almost half of the Galactic Plane (251○ ≤l ≤ 358○ and 2○ ≤l ≤ 61○ at |b| ≤ 1 5). SMGPS is the largest, most sensitive and highest angular resolution 1 GHz survey of the Plane yet carried out, with an angular resolution of 8″ and a broadband RMS sensitivity of ∼10–20 μJy beam−1. Here we describe the first publicly available data release from SMGPS which comprises data cubes of frequency-resolved images over 908–1656 MHz, power law fits to the images, and broadband zeroth moment integrated intensity images. A thorough assessment of the data quality and guidance for future usage of the data products are given. Finally, we discuss the tremendous potential of SMGPS by showcasing highlights of the Galactic and extragalactic science that it permits. These highlights include the discovery of a new population of non-thermal radio filaments; identification of new candidate supernova remnants, pulsar wind nebulae and planetary nebulae; improved radio/mid-IR classification of rare Luminous Blue Variables and discovery of associated extended radio nebulae; new radio stars identified by Bayesian cross-matching techniques; the realisation that many of the largest radio-quiet WISE H II region candidates are not true H II regions; and a large sample of previously undiscovered background H I galaxies in the Zone of Avoidance

    Magnetohydrodynamic Oscillations in the Solar Corona and Earth’s Magnetosphere: Towards Consolidated Understanding

    Full text link
    corecore