Electronic transport in disordered organic and inorganic semiconductors

It is shown that theoretical methods developed for a description of hopping transport in disordered inorganic solids can be also successfully applied to a description of hopping transport in organic disordered materials, such as conjugated polymers, molecularly doped polymers and organic glasses. While the density of localized states (DOS) in inorganic materials is believed to be exponential. a Gaussian DOS has been suggested for organic disordered materials. The most powerful and rigorous theoretical method for the description of variable-range hopping (VRH) in the exponential DOS is based on percolation theory. We show that this percolation approach is also valid for systems with a Gaussian DOS. thus being universal for inorganic and organic disordered materials. (C) 2002 Elsevier Science B.V. All rights reserved.