A simple technique to measure the minority carrier mobility using a bipolar junction transistor is demonstrated. By fixing the base-emitter voltage, the carrier injection into the base is constant. The collector current is then monitored as a function of a magnetic field applied perpendicular to the current transport across the base. The magnetic field leads to an increase in base transit time and a corresponding decrease in collector current. From the resulting fractional change in collector current, the minority carrier mobility in the base can be determined. For narrow base transistors, quasiballistic transport across the base must be taken into account when determining the bulk minority carrier mobility.


Copyright (1997) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett., Vol. 70, No. 4, 27 January 1997 and may be found at http://dx.doi.org/10.1063/1.118185. The following article has been submitted to/accepted by Applied Physics Letters. Copyright (1997) S. L. D’Souza, M. R. Melloch, M. S. Lundstrom, and E. S. Harmon. This article is distributed under a Creative Commons Attribution 3.0 Unported License.

Date of this Version


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Applied Physics Letters: Volume 70, Issue 4. 10.1063/1.118185



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