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Title: Influence of bias stressing and irradiation on poly-three-hexylthiophene based field effect transistors

Abstract

Preliminary measurements of positive and negative bias stress and radiation effects in poly-three-hexylthiophene based field effect transistors are reported. Radiation up to 0.5 Mrad (SiO{sub 2}) is found to have little effect on channel carrier mobility though bias stressing does. A strong positive bias stress induced positive threshold voltage shift is suppressed when devices are simultaneously irradiated. There is no evidence for significant radiation effects in the organic semiconductor. Recovery effects are observed following removal of bias stress and radiation.

Authors:
 [1]
  1. AFRL-VSSE, Space Vehicles Directorate, 3550 Aberdeen Avenue, Kirtland AFB, New Mexico 87117 (United States)
Publication Date:
OSTI Identifier:
20788090
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 8; Other Information: DOI: 10.1063/1.2189936; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARRIER MOBILITY; ELECTRIC POTENTIAL; FIELD EFFECT TRANSISTORS; IRRADIATION; ORGANIC SEMICONDUCTORS; PHYSICAL RADIATION EFFECTS; SILICON OXIDES; STRESSES

Citation Formats

Devine, R. A. B. Influence of bias stressing and irradiation on poly-three-hexylthiophene based field effect transistors. United States: N. p., 2006. Web. doi:10.1063/1.2189936.
Devine, R. A. B. Influence of bias stressing and irradiation on poly-three-hexylthiophene based field effect transistors. United States. doi:10.1063/1.2189936.
Devine, R. A. B. Sat . "Influence of bias stressing and irradiation on poly-three-hexylthiophene based field effect transistors". United States. doi:10.1063/1.2189936.
@article{osti_20788090,
title = {Influence of bias stressing and irradiation on poly-three-hexylthiophene based field effect transistors},
author = {Devine, R. A. B.},
abstractNote = {Preliminary measurements of positive and negative bias stress and radiation effects in poly-three-hexylthiophene based field effect transistors are reported. Radiation up to 0.5 Mrad (SiO{sub 2}) is found to have little effect on channel carrier mobility though bias stressing does. A strong positive bias stress induced positive threshold voltage shift is suppressed when devices are simultaneously irradiated. There is no evidence for significant radiation effects in the organic semiconductor. Recovery effects are observed following removal of bias stress and radiation.},
doi = {10.1063/1.2189936},
journal = {Journal of Applied Physics},
number = 8,
volume = 99,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
  • A comparative study on electrical performance, optical properties, and surface morphology of poly(3-hexylthiophene) (P3HT) and P3HT-nanofibers based “normally on” type p-channel field effect transistors (FETs), fabricated by two different coating techniques has been reported here. Nanofibers are prepared in the laboratory with the approach of self-assembly of P3HT molecules into nanofibers in an appropriate solvent. P3HT (0.3 wt. %) and P3HT-nanofibers (∼0.25 wt. %) are used as semiconductor transport materials for deposition over FETs channel through spin coating as well as through our recently developed floating film transfer method (FTM). FETs fabricated using FTM show superior performance compared to spin coated devices;more » however, the mobility of FTM films based FETs is comparable to the mobility of spin coated one. The devices based on P3HT-nanofibers (using both the techniques) show much better performance in comparison to P3HT FETs. The best performance among all the fabricated organic field effect transistors are observed for FTM coated P3HT-nanofibers FETs. This improved performance of nanofiber-FETs is due to ordering of fibers and also due to the fact that fibers offer excellent charge transport facility because of point to point transmission. The optical properties and structural morphologies (P3HT and P3HT-nanofibers) are studied using UV-visible absorption spectrophotometer and atomic force microscopy , respectively. Coating techniques and effect of fiber formation for organic conductors give information for fabrication of organic devices with improved performance.« less
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