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Title: Organic-inorganic proximity effect in the magneto-conductance of vertical organic field effect transistors

Abstract

Vertical organic field effect transistors having a patterned source electrode and an a-SiO{sub 2} insulation layer show high performance as a switching element with high transfer characteristics. By measuring the low field magneto-conductance under ambient conditions at room temperature, we show here that the proximity of the inorganic a-SiO{sub 2} insulation to the organic conducting channel affects considerably the magnetic response. We propose that in n-type devices, electrons in the organic conducting channel and spin bearing charged defects in the inorganic a-SiO{sub 2} insulation layer (e.g., O{sub 2} = Si{sup +·}) form oppositely charged spin pairs whose singlet-triplet spin configurations are mixed through the relatively strong hyperfine field of {sup 29}Si. By increasing the contact area between the insulation layer and the conducting channel, the ∼2% magneto-conductance response may be considerably enhanced.

Authors:
; ;  [1]; ;  [2]
  1. Physics Department and Solid State Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel)
  2. Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel)
Publication Date:
OSTI Identifier:
22594483
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DEFECTS; ELECTRODES; ELECTRONS; FIELD EFFECT TRANSISTORS; LAYERS; N-TYPE CONDUCTORS; PROXIMITY EFFECT; SILICA; SILICON 29; SILICON IONS; SILICON OXIDES; SPIN; TEMPERATURE RANGE 0273-0400 K; TRIPLETS

Citation Formats

Khachatryan, B., Devir-Wolfman, A. H., Ehrenfreund, E., E-mail: eitane@technion.ac.il, Greenman, M., and Tessler, N.. Organic-inorganic proximity effect in the magneto-conductance of vertical organic field effect transistors. United States: N. p., 2016. Web. doi:10.1063/1.4959271.
Khachatryan, B., Devir-Wolfman, A. H., Ehrenfreund, E., E-mail: eitane@technion.ac.il, Greenman, M., & Tessler, N.. Organic-inorganic proximity effect in the magneto-conductance of vertical organic field effect transistors. United States. doi:10.1063/1.4959271.
Khachatryan, B., Devir-Wolfman, A. H., Ehrenfreund, E., E-mail: eitane@technion.ac.il, Greenman, M., and Tessler, N.. 2016. "Organic-inorganic proximity effect in the magneto-conductance of vertical organic field effect transistors". United States. doi:10.1063/1.4959271.
@article{osti_22594483,
title = {Organic-inorganic proximity effect in the magneto-conductance of vertical organic field effect transistors},
author = {Khachatryan, B. and Devir-Wolfman, A. H. and Ehrenfreund, E., E-mail: eitane@technion.ac.il and Greenman, M. and Tessler, N.},
abstractNote = {Vertical organic field effect transistors having a patterned source electrode and an a-SiO{sub 2} insulation layer show high performance as a switching element with high transfer characteristics. By measuring the low field magneto-conductance under ambient conditions at room temperature, we show here that the proximity of the inorganic a-SiO{sub 2} insulation to the organic conducting channel affects considerably the magnetic response. We propose that in n-type devices, electrons in the organic conducting channel and spin bearing charged defects in the inorganic a-SiO{sub 2} insulation layer (e.g., O{sub 2} = Si{sup +·}) form oppositely charged spin pairs whose singlet-triplet spin configurations are mixed through the relatively strong hyperfine field of {sup 29}Si. By increasing the contact area between the insulation layer and the conducting channel, the ∼2% magneto-conductance response may be considerably enhanced.},
doi = {10.1063/1.4959271},
journal = {Applied Physics Letters},
number = 3,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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