Spectral Response Behavior in Single-Layer Organic Semiconductor Devices in Relation to its Absorption Spectrum

Abstract

Improved understanding of spectral response in organic semiconductor devices can be useful for building better performing devices as well as using them for newer optoelectronic applications. The nature of the spectral response for single-layer organic semiconductor devices depends on the dominant charge carrier (either electron or holes) in the absorbing layer. The exponential dependence of charge carrier mobility on electric field means that the applied bias and absorption layer thickness can affect and possibly help tune the spectral response of the device. In this paper, the spectral response for such devices has been modeled and the parameters and conditions determining either antibatic or symbatic response with respect to the absorption spectrum of the active layer have been presented. The spectral responses in a donor-type poly (3-hexylthiophene-2, 5-diyl) as well as an acceptor-type fullerene- C 60 single-layer devices have been analyzed with the help of the model. Besides giving insight into the optoelectronic phenomenon, the results point to the ability to tune organic semiconductor device spectral response that can be useful for optical demultiplexing applications.