Conjugation effects on carrier mobilities of polythiophenes probed by time-resolved terahertz spectroscopy

Esentürk, Okan
Deongchamp, Dean M.
Heilweil, Edwin J.
Optically generated carrier conductivity of thiophene-based spin-cast polymer films, as cast poly(3-hexylthiophene) (P3HT) and both as cast and above liquid crystalline temperature annealed poly(2,5-bis(3tetradecylthiophen-2yl)thieno[3,2-b]thiophene) (PBTTT), were measured by time-resolved THz spectroscopy (TRTS) and compared to reported thin-film transistor (TFT) device measurements. The relative mobilities of the samples measured by TRTS agree well with reported TFl` mobilities. Since TRTS is sensitive to shortrange carrier mobility, this study suggests that increased mobility of PBTTT relative to P3HT films arises from improved ordering of the local structure, increased effective conjugation length, and planarity of PBTTT molecules in the solid state.


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X-ray diffraction, scanning electron microscopy, compositional analysis and transmission measurements are performed on InSe thin films grown by thermal evaporation at different substrate and annealing temperatures of 150-250 degrees C and 100-200 degrees C, respectively. An analysis of structural measurements indicates that there exist three phases of In-Se system like InSe, In2Se3 and In6Se7 in the same film at low-substrate temperature, but at high-substrate temperatures, In2Se3 phase was absent. The comp...
Citation Formats
O. Esentürk, D. M. Deongchamp, and E. J. Heilweil, “Conjugation effects on carrier mobilities of polythiophenes probed by time-resolved terahertz spectroscopy,” JOURNAL OF PHYSICAL CHEMISTRY C, pp. 10587–10590, 2008, Accessed: 00, 2020. [Online]. Available: