Photoconductivity of organic semiconductor polymers studied by time-resolved THz-TDS

Date

2007-12-01

Author

Esentürk, Okan
Heilweil, Edwin J.

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This study employs optical-pump terahertzprobe time-domain spectroscopy to measure relative carrier mobilities of semiconductor organic polymer films of poly-3-hexylthiophene (P3HT) and poly(2,5-bis(3-tetradecylthiophen-2-yi) thieno[3,2-b]thiophene) (PBTTT) polymers and these results directly correlate to recently reported electrical device mobility measurements.. An approximately four-fold increase in mobility of P3HT is observed with molecular weight increase from c.a. 18 kD to 150 kD where the intrinsic film mobility saturates for molecular weight > 70 kD. The decay dynamics studies of these polymers showed almost no dependence on the molecular weight of the polymer. The studies also showed an order of magnitude increase in mobility between as cast P3HT films and annealed PBTTT films supporting a strong conjugation length effect. We also measured the mobility dependence on the film quality that is affected by regularity of the polymer, dispersing solvent, electron acceptor traps, and other film growth related parameters relevant to device manufacturing.

Subject Keywords

Conductivity, Dynamics, Organic semiconductors, Relative mobility, THz or terahertz

URI

https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=77951153113&origin=inward
https://hdl.handle.net/11511/77524

DOI

https://doi.org/10.1109/icimw.2007.4516675

Conference Name

Joint International Conference on Infrared and Millimetre Waves, and 15th International Conference on Terahertz Electronics, IRMMW-THz2007, (03 - 07 Eylül 2007)

Collections

Department of Chemistry, Conference / Seminar

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Citation Formats

O. Esentürk and E. J. Heilweil, “Photoconductivity of organic semiconductor polymers studied by time-resolved THz-TDS,” Cardiff, İngiltere, 2007, p. 670, Accessed: 00, 2021. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=77951153113&origin=inward.