title: Electrical characterization of photodetectors based on poly(3-hexylthiophene-2,5-diyl) layers.
abstract: This paper presents the electrical characteristics of solution-processed organic photodetectors based on poly(3-hexylthiophene-2,5-diyl) semiconducting polymer layers deposited by spin-coating on interdigitated metal electrodes. Four different electrode shapes have been used for this study in order to appraise the optimum electrode geometry. The measurement of the resistance as a function of the temperature reveals a transition from negative to positive temperature coefficient material around 80 °C for the polymer layers. Besides, slow reversible changes in the photodetectors conductivity were observed when moved from vacuum to the air and under illumination with a xenon lamp, which can be explained by the formation of charge transfer complexes with molecular oxygen and the polymer. The photogenerated current-light power ratio was found to be approximately linear in the 200 to 550 mW/cm2 range.
authors.affiliation: Área de Electrónica, Universidad Miguel Hernández, Av. Universidad s/n, Ed. Quorum V, Elche 03202, Spain. jc.ferrer@umh.es.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Ferrer
authors.affiliation: Área de Electrónica, Universidad Miguel Hernández, Av. Universidad s/n, Ed. Quorum V, Elche 03202, Spain. j.l.alonso@umh.es.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Alonso
authors.affiliation: Área de Electrónica, Universidad Miguel Hernández, Av. Universidad s/n, Ed. Quorum V, Elche 03202, Spain. s.fdezavila@umh.es.
authors.forename: Susana Fernández
authors.initials: SF
authors.lastname: de Ávila