Electrochemical overoxidation patterning

Figure 4.13 illustrates several techniques for patterning PEDOT PSS via electrochemical overoxidation. Conversion of a simple plotter pen or a screen-printing station are relatively straightforward, the latter allowing print resolution of a few hundred micrometers. To demonstrate that the technique is limited only by the resolution of the printing method, 2 p,m lines (the smallest mask available) were patterned in a 200 nm thick film with the aid of a photoresist mask [29]. 

FIGURE 4.13 Electrochemical overoxidation techniques for use with polythiophenes, (a) A plotter pen modified to be used in an electrochemical cell, (b) Screen-printing electrochemical cell, (c) Photoresist patterned on a PEDOT PSS film protects areas of the film from overoxidation whereas the rest is patterned when wet by the liquid electrolyte. (Images from Tehrani, P., Remonen, T., Hennerdal, L.-O., Hall, J., Malmstrom, A., Leenders, L., Kugler, T., Robinson, N.D., Crispin, X., Fahlman, M., and Berggren, M., Smart Mater Struct 14, N21-N25. Copyright 2005, Institute of Physics Publishing. With permission.)... 

Tehrani, R, N.D. Robinson, T. Kugler, T. Remonen, L.-O. Hennerdal, J. Hall, A. Malmstrom, L. Leenders, and M. Berggren. 2005. Patterning polythiophene films using electrochemical overoxidation. Smart Mater Struct 14 N21-N25. 

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