Steady-state photoconduction was studied in typically 100-nm-thick films of a polyphenylenevinylene derivative with ether linkages in the backbone. Samples were prepared in sandwich configuration between indium tin oxide ͑ITO͒ and Al electrodes. Forward photocurrents measured upon irradiating through the positively biased ITO electrode decreased by typically three orders of magnitude when a 8-10-nm-thick silicon monoxide ͑SiO͒ layer had been deposited on top of the ITO to prevent photoinjection of positive charge carriers. Insertion of a SiO layer can thus be used as a tool to separate extrinsic from intrinsic sources of optical charge-carrier generation. Analysis of the dependences of extrinsic and intrinsic photocurrents on temperature, electric field, and photon energy indicate that they can be described in terms of Onsager's theory of geminate pair dissociation in either one or three dimensions.
Detailed investigations on shelf life and operation lifetime of polymer field-effect transistors (PFETs) and circuits are reported. All examined devices consisted entirely of polymer materials except the electrodes. Regioregular poly(3-alkylthiophene) was used as a semiconductor. Unencapsulated devices were produced, stored, and measured under ambient conditions. The performance of PFETs was maintained for more than 12 months after production. Even under extreme conditions of 85 °C and 85% relative humidity, a stable shelf life of more than 1400 h was measured. Transistors exceeded a continuous operation time of 1000 h. Operation lifetimes showed that the degradation did not follow the Arrhenius lifetime-temperature relationship. Similar results were found for ring oscillators.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.