A novel technique to measure interface trap density in a GaAs MOS capacitor using time-varying magnetic fields

Journal Article · Mon May 23 00:00:00 EDT 2016 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4948082· OSTI ID:22608816

Choudhury, Aditya N. Roy,; Venkataraman, V. ^[1]

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1. Dept. of Physics, Indian Institute of Science, Bangalore – 560012 (India)

Interface trap density (D{sub it}) in a GaAs metal-oxide-semiconductor (MOS) capacitor can be measured electrically by measuring its impedance, i.e. by exciting it with a small signal voltage source and measuring the resulting current through the circuit. We propose a new method of measuring D{sub it} where the MOS capacitor is subjected to a (time-varying) magnetic field instead, which produces an effect equivalent to a (time-varying) voltage drop across the sample. This happens because the electron chemical potential of GaAs changes with a change in an externally applied magnetic field (unlike that of the gate metal); this is not the voltage induced by Faraday’s law of electromagnetic induction. So, by measuring the current through the MOS, D{sub it} can be found similarly. Energy band diagrams and equivalent circuits of a MOS capacitor are drawn in the presence of a magnetic field, and analyzed. The way in which a magnetic field affects a MOS structure is shown to be fundamentally different compared to an electrical voltage source.

• OSTI ID: 22608816
• Journal Information: AIP Conference Proceedings, Vol. 1731, Issue 1; Conference: DAE solid state physics symposium 2015, Uttar Pradesh (India), 21-25 Dec 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COMPARATIVE EVALUATIONS
CRYSTAL DEFECTS
CURRENTS
ELECTRIC POTENTIAL
ELECTRONIC STRUCTURE
ELECTRONS
EQUIVALENT CIRCUITS
GALLIUM ARSENIDES
IMPEDANCE
INTERFACES
MAGNETIC FIELDS
METALS
SEMICONDUCTOR MATERIALS
SILICON OXIDES
TRAPS
VOLTAGE DROP