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Tunable molecular orientation and elevated thermal stability of vapor-deposited organic semiconductors

Journal Article · · Proceedings of the National Academy of Sciences of the United States of America
 [1];  [1];  [2];  [2];  [1]
  1. Department of Chemistry, University of Wisconsin–Madison, Madison, WI 53706, and
  2. Institute for Molecular Engineering, University of Chicago, Chicago, IL 60637
Significance

Glasses are solids that lack the regular order of crystals. Organic glasses, when produced by deposition from the vapor, can exhibit high levels of molecular orientation that improve performance of devices such as organic light-emitting diodes. We show here that molecular orientation in such glasses is primarily controlled by the substrate temperature during deposition, suggesting that the performance of almost any device based upon amorphous organic materials might be systematically optimized by this route. We explain molecular orientation in the glass in terms of the orientation present near the surface of the corresponding liquid. The highly oriented glasses formed here also exhibit high density and improved thermal stability. These features will likely further enhance the performance of organic electronics devices.

Research Organization:
Univ. of Wisconsin, Madison, WI (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Grant/Contract Number:
SC0002161
OSTI ID:
1235168
Alternate ID(s):
OSTI ID: 1348214
Journal Information:
Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 14 Vol. 112; ISSN 0027-8424
Publisher:
Proceedings of the National Academy of SciencesCopyright Statement
Country of Publication:
United States
Language:
English

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