A simple one-speed solution to the Boltzmann equation is used to evaluate the mobility and diffusion coefficient for carriers in forward-biased semiconductor barriers. The analysis shows that although the average kinetic energy of carriers remains near thermal equilibrium, the mobility and diffusion coefficient are strongly reduced by the built-in field. Conventional macroscopic transport equations, which treat the carrier mobility and diffusion coefficient as single valued functions of the kinetic energy will improperly treat transport in forward-biased barriers. The results are important for the careful analysis of metal–semiconductor and heterojunction diodes.


Copyright (1995) 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. 66 (8), 20 February 1995 and may be found at http://dx.doi.org/10.1063/1.113611. The following article has been submitted to/accepted by Applied Physics Letters. Copyright (1995) Mark Lundstrom & Shin’ichi Tanaka. This article is distributed under a Creative Commons Attribution 3.0 Unported License.

Date of this Version


Published in:

On the carrier mobility in forward-biased semiconductor barriers Mark Lundstrom and Shin’ichi Tanaka. Appl. Phys. Lett. 66 (8), 20 February 1995



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.