Charge carrier mobility in organic nanostructures

摘要

Based on two recent review articles [01K1,01K2] it was tried to give a broad overview on charge carrier transport in well-ordered organic crystals. It has been shown that mobilities in well-ordered, high-purity organic crystals can be rather large, approaching or even exceeding values at low temperature which are typical for silicon at room temperature, a fact which supports a conventional band-type description for the low temperature regime. The smooth continuation of a band-type μ ∝ T~n(-3 < n < -1) power law decrease 'of mobility with rising temperature up to room temperature and above is not yet fully understood. There are examples where a subsequent transition to a hopping-type transport regime has been observed and it seems that there is a universal crossover from band to hopping conduction at sufficiently elevated temperatures [01S]. The broad and much more intricate field of low mobility dispersive transport in (more or less) disordered organic solids, which in the eyes of the author will have, at best, only limited practical importance for future electronic applications, has been omitted.