Carrier Injection Into Low Lifetime (Relaxation) Semiconductors

  • J. C. Manifacier
  • Y. Moreau
  • R. Ardebili
Part of the Institute of Amorphous Studies Series book series (IASS)


The paper deals with the consequences of a steady state minority carrier injection through a metal or a high-low junction into the bulk of a semiconductor. Depending on the nature of the semiconductor, the spatial distribution of the net recombination rate of injected minority carriers R occurs in two different ways:
  1. (i)

    When the lifetime, T o of the excess electron-hole pairs is much higher than the dielectric relaxation time T Dspace charge vanishes in a distance on the order of thescreening length Ls. Ls reduces to the Debye length LD if trapped space charge can be neglected. The injectedminority carriers and the neutralizing majority carriersdecrease then with a characteristic ambipolar diffusionlength LDa » Lsand so does the rate of recombination R.

  2. (ii)

    A second class of semiconductors (relaxationsemiconductors) are characterized by Ls » LDa. Theys Darespond to injection in an entirely different way. The recombination rate is now highly localized inside a recombination front whose extension is of the order of LDa and whose position is current dependent. Resultsobtained by numerical simulation and analytical modeling are presented.



Space Charge Recombination Rate Minority Carrier Space Charge Region Recombination Center 
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Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • J. C. Manifacier
    • 1
  • Y. Moreau
    • 1
  • R. Ardebili
    • 1
  1. 1.Centre d’Electronique de MontpellierUniversite des Sciences et Techniques du LanguedocMontpellier CedexFrance

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