Hall Effect in Semiconductors

摘要: The Hall effect, which was discovered in 1879, determines the concentration and type (negative or positive) of charge carriers metals, semiconductors, insulators. In general, method is used conjunction with a conductivity measurement to also determine mobility (ease movement) carriers. At low temperatures high magnetic fields, quantum effects are sometimes evident lower dimensional structures; however, such not be considered here. Also, this article concentrates on rather than metals insulators, although same theory generally applies. Three, strong advantages effect measurements ease instrumentation, interpretation, wide dynamic range. With respect implementation, only elements necessary, at lowest level, current source, voltmeter, modest-sized magnet. carrier can then calculated within typical accuracy 20% without any other information about material. Measurments concentrations ranging from 104 1020 cm−3 have been obtained. (n p) unambiguously determined sign voltage. Competing techniques include capacitance-voltage (C-V) concentration; thermoelectric probe (TEP) type; magnetoresistance (MR) mobility. Keywords: hall effect; principles; semiconductors; charge carriers; metals; insulators; practical aspects; van der pauw results; data analysis; initial interpretation; sample preparation; problems; depletion effects; inhomogeneity; nonohmic contracts; contact size