Visualization of electrochemical doping and light-emitting junction formation in conjugated polymer films

Gao, Jun; Dane, Justin
April 2004
Applied Physics Letters;4/12/2004, Vol. 84 Issue 15, p2778
Academic Journal
In situ electrochemical doping and light-emitting junction formation in conjugated polymer films have been visualized by direct imaging of a massive planar device structure under UV illumination. Both p- and n-doping of conjugated polymers have been observed. When the p- and n-doped regions meet, a light-emitting p–n junction forms and significant current flow begins. The reversal of applied bias creates many tiny and transient light-emitting p–n junctions in the previously n-doped region by the uneven growth of new p-doped areas. Eventually a stable emission zone is formed closer to the new cathode, from a polymer film that shows almost no photoluminescence due to doping. © 2004 American Institute of Physics.


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