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Very Low Degree of Energetic Disorder as the Origin of High Mobility in an n ‐channel Polymer Semiconductor
Author(s) -
Caironi Mario,
Bird Matt,
Fazzi Daniele,
Chen Zhihua,
Di Pietro Riccardo,
Newman Christopher,
Facchetti Antonio,
Sirringhaus Henning
Publication year - 2011
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.201100592
Subject(s) - materials science , electron mobility , induced high electron mobility transistor , charge (physics) , semiconductor , transistor , field effect transistor , organic semiconductor , charge carrier , activation energy , electron transport chain , coupling (piping) , optoelectronics , condensed matter physics , chemical physics , electrical engineering , voltage , chemistry , physics , biochemistry , quantum mechanics , metallurgy , engineering
Charge transport is investigated in high‐mobility n ‐channel organic field‐effect transistors (OFETs) based on poly{[ N , N ′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (P(NDI2OD‐T2), Polyera ActivInk™ N2200) with variable‐temperature electrical measurements and charge‐modulation spectroscopy. Results indicate an unusually uniform energetic landscape of sites for charge‐carrier transport along the channel of the transistor as the main reason for the observed high‐electron mobility. Consistent with a lateral field‐independent transport at temperatures down to 10 K, the reorganization energy is proposed to play an important role in determining the activation energy for the mobility. Quantum chemical calculations, which show an efficient electronic coupling between adjacent units and a reorganization energy of a few hundred meV, are consistent with these findings.