Charge and Current in Solids: The Classical Drift–Diffusion Model

  • Supriyo Bandyopadhyay


The first chapter reviews the steady-state “drift–diffusion model” of charge transport in solids that electrical engineers typically learn in their first undergraduate solid state device course. Physics undergraduates are less exposed to this topic, but should be able to grasp the concept easily. This chapter introduces the basic drift–diffusion model, starting with two important assumptions about the nature of charge conduction in solids, and emphasizes the notion that this model is valid only as long as nonlocal transport effects are absent. It ends with an introduction to the so-called “equations of state” (also known as drift–diffusion equations) that are used to compute the carrier concentration and current density in a solid state device self-consistently. Only steady-state transport is considered.


Diffusion Model Drift Velocity Local Electric Field Drude Model Drift Mobility 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    B. K. Ridley and T. B. Watkins, “The possibility of negative resistance effect in semiconductors”, Proc. Phys. Soc. Lond., 78, 293 (1961).CrossRefGoogle Scholar
  2. 2.
    C. Hilsum, “Transferred electron amplifiers and oscillators”, Proc. IRE, 50, 185 (1962).CrossRefGoogle Scholar
  3. 3.
    J. B. Gunn, “Microwave oscillation of current in III-V semiconductors”, Solid State Commun., 1, 88 (1963).CrossRefGoogle Scholar
  4. 4.
    S. Bandyopadhyay, M. E. Klausmeier-Brown, C. M. Maziar, S. Datta and M. S. Lundstrom, “A rigorous technique to couple Monte Carlo and drift–diffusion models for computationally efficient device simulation”, IEEE Trans. Elec. Dev., 34, 392 (1987).CrossRefGoogle Scholar
  5. 5.
    S. M. Sze, Physics of Semiconductor Devices, 2nd. edition, (John Wiley & Sons, New York, 1981).Google Scholar
  6. 6.
    R. F. Pierret, Semiconductor Device Fundamentals (Addison Wesley Longman, Reading, Massachusetts, 1996).Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Supriyo Bandyopadhyay
    • 1
  1. 1.Department of Electrical and Computer EngineeringVirginia Commonwealth UniversityRichmondUSA

Personalised recommendations