Room-temperature bandlike transport and Hall effect in a high-mobility ambipolar polymer


Type
Article
Change log
Authors
Senanayak, SP 
Ashar, AZ 
Kanimozhi, C 
Patil, S 
Narayan, KS 
Abstract

The advent of new-class of high-mobility semiconducting polymers opens up a window to address fundamental issues in electrical transport mechanism such as hopping between localized states versus extended state conduction. Here, we investigate the origin of ultra-low degree of disorder (~ 16 meV) and band-like negative temperature (T) coefficient of the field effect electron mobility in a high performance diketopyrrolopyrrole (DPP)-based semiconducting polymer. Models based on the framework of mobility edge (ME) with exponential density of states are invoked to explain the trends in transport. The temperature window over which the system demonstrates de-localized transport was tuned by a systematic introduction of disorder at the transport interface. Additionally, the Hall mobility extracted from Hall-voltage measurements in these devices was found to be comparable to field effect mobility in the high T band-like regime. Comprehensive studies with different combinations of dielectrics and semiconductors demonstrate the effectiveness of rationale molecular design which emphasizes uniform-energetic landscape and low re-organization energy.

Description
Keywords
cond-mat.mtrl-sci, cond-mat.mtrl-sci
Journal Title
Physical Review B - Condensed Matter and Materials Physics
Conference Name
Journal ISSN
1098-0121
1550-235X
Volume Title
91
Publisher
American Physical Society (APS)
Sponsorship
Engineering and Physical Sciences Research Council (EP/M023532/1)