Key points are not available for this paper at this time.
A flaw with s electronic units of negative charge makes transitions to charge s+1 by hole emission at rate e (p, s) or by electron capture at rate nc (n, s) and returns to charge s at rates e (n, s+1) and pc (p, s+1). Here n is the electron density in the conduction band and p is the hole density in the valence band. The steady-state ratio of populations Nₒ+₁ to Nₒ is given by c (n, s) n+n^{* (s+12) }c (p, s+1) p+{p^* (s+12) }, where n^* (s+12) =e (p, s) c (n, s) and p^* (s12) =e (n, s+1) c (p, s+1). This distribution corresponds to an effective Fermi level for the flaws only for the condition of thermal equilibrium. Expressions for the recombination rate based on the steady-state distribution are derived. For a given transition s+1 the following special cases are defined: (1) denuded: nn^*, pp^*; (4) flooded: n>n^*, p>p^*. Diagrams which aid in visualizing the relative importance of the various transitions are presented. Some speculations on the nature of trapping centers are given.
Sah et al. (1958) studied this question.