Mobility spatial distribution function: Comparative method for conjugated polymers/molecules

The authors report improved method for extracting mobility spatial distribution function that accounts for the finite light-absorption depth. They employ step function light excitation and use the photocurrent temporal response to extract the electrons' mobility spatial distribution function (MDF). This directly measures the relevant electronic disorder in amorphous conjugated polymers. Comparing two different polymers shows that qualitative analysis of field effect transistor data is in good agreement with the quantitative analysis provided by the MDF concept/method. The better uniformity of the electronic properties found in green polypnenylene vinylene is a clear indication for its better performance and lifetime. (c) 2006 American Institute of Physics.