Oxidative and initiated chemical vapor deposition for application to organic electronics

Since the first discovery of polymeric conductors in 1977, the research area of "organic electronics" has grown dramatically. However, methods for forming thin films comprised solely of conductive polymers are limited by the rigid nature of the conjugated backbone. Neither spin casting from solution nor melt processing can be used. To answer to this challenge, a solvent-free method of oxidative chemical vapor deposition (oCVD) to synthesize conductive poly (3, 4-ethylenedioxythiophene) (PEDOT) films was demonstrated. The substrate temperature systemically controls the conjugation length, resulting in films with conductivity of 9.1 x 10-4 to 348 S/cm. The highest conductivity was about 1000 S/cm. The doping level could also be tuned with substrate temperature. Consequently, the work function was varied from 5.1 to 5.4 eV. The polymerization rate could be modulated with various oxidants, which significantly affects the surface morphology of PEDOT film. With milder oxidant, the surface morphology was highly nano-porous. Conformal coverage of PEDOT was also observed on trench structures and paper mats. Furthermore, with this one-step method, PEDOT film could be grafted on various kinds of organic substrates. Huge increase in adhesion strength was consistently observed. With this grafting technique, nanometer-scale PEDOT pattern was firstly obtained on flexible substrates down to 60 nm.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Im, Sung Gap

Advisor dc:contributor.advisor

• Karen K. Gleason.

• Chemical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/46599

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/46599