Temperature and composition-dependent density of states in organic small-molecule/polymer blend transistors
File(s)S. Hunter et al. JAP_120_2025502_2016.pdf (1.89 MB)
Accepted version
Author(s)
Hunter, S
Mottram, AD
Anthopoulos, TD
Type
Journal Article
Abstract
The density of trap states (DOS) in organic p-type transistors based on the small-molecule 2,8-difluoro-5,11-bis(triethylsilylethynyl) anthradithiophene (diF-TES ADT), the polymer poly(triarylamine) and blends thereof are investigated. The DOS in these devices are measured as a function of semiconductor composition and operating temperature. We show that increasing operating temperature causes a broadening of the DOS below 250 K. Characteristic trap depths of ∼15 meV are measured at 100 K, increasing to between 20 and 50 meV at room-temperature, dependent on the semiconductor composition. Semiconductor films with high concentrations of diF-TES ADT exhibit both a greater density of trap states as well as broader DOS distributions when measured at room-temperature. These results shed light on the underlying charge transport mechanisms in organic blend semiconductors and the apparent freezing-out of hole conduction through the polymer and mixed polymer/small molecule phases at temperatures below 225 K.
Date Issued
2016-07-14
Date Acceptance
2016-06-23
Citation
Journal of Applied Physics, 2016, 120 (2)
ISSN
1089-7550
Publisher
American Institute of Physics (AIP)
Journal / Book Title
Journal of Applied Physics
Volume
120
Issue
2
Copyright Statement
Copyright © 2016 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in J. Appl. Phys. 120, 025502 (2016); and may be found at https://dx.doi.org/10.1063/1.4955282.
Subjects
Science & Technology
Physical Sciences
Physics, Applied
Physics
FIELD-EFFECT TRANSISTORS
THIN-FILM TRANSISTORS
HIGH-MOBILITY
SEMICONDUCTING POLYMERS
TRANSPORT
Publication Status
Published
Article Number
025502