COMBINATORIAL SCREENING OF THE EFFECT OF TEMPERATURE ON THE MICROSTRUCTURE AND MOBILITY OF A HIGH-PERFORMANCE POLYTHIOPHENE SEMICONDUCTOR

 

Leah A. Lucas1, Dean M. DeLongchamp2, Brandon M. Vogel2, Eric K. Lin2, Michael J. Fasolka2, Daniel A. Fischer2, Iain McCulloch3, Martin Heeney3, and Ghassan E. Jabbour1

 

1Arizona State University, Department of Chemical and Materials Engineering and Flexible Display Center, Tempe, AZ, 85284

 

2Polymers Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899

 

3Merck Chemicals, Chilworth Science Park, Southampton S016 7QD, UK

 

 

Abstract

 

We use a continuous combinatorial temperature gradient to evaluate the effect of temperature on the microstructure and mobility of a recently reported high performance polymer semiconductor, poly(2,5-bis(3-dodecylthiophen-2yl)thieno[3,2-b]thiophene (pBTTT‑C12), for application in organic field-effect transistors (OFETs).  Microstructure varies greatly due to changes in processing conditions such as casting solvent or spin speed.  The microstructure critically affects charge transport and the ultimate performance of the OFET.  Combinatorial analysis is an excellent way to cover this large parameter space.  The gradient heating revealed a detailed dependence on thermal history.  Optimal heat treatment achieved mobilities as high as 0.3 cm2V‑1s-1.  Mobility enhancement coincides with an increase in crystal domain size and orientation, all of which occur abruptly at a temperature closely corresponding to a bulk liquid crystal phase transition.

 

 

 

Author Information:

Leah Lucas

Dean DeLongchamp, Mentor

Polymers Division, MSEL

Building 224, Room B204, Mail Stop 8542

301-975-6488 (phone)

301-975-4924 (fax)

leah.lucas@nist.gov

Sigma Xi: No

Category: Materials