Influence of intensive light exposure on polymer field-effect transistors

The influence of intensive light exposure on high performance polymer field-effect transistors containing highly regioregular poly(3-alkylthiophene) as a semiconductor is reported. While the transistors show high stability under ambient air and light, a distinct degradation upon exposure to intensive light could be detected by its impact on the on currents. UV-Vis spectra were used to interpret the current decrease as being caused by a decrease of the conjugation length of the semiconductor, which is supported by IR spectrometry. The role of ambient air, in particular, oxygen, in the degradation process is shown. (C) 2004 American Institute of Physics.