Photopatterned semiconductor nanocrystals and their electroluminescence from hybrid light-emitting devices

We demonstrate the ability to use a photolithographic method to make patterned nanocrystal film for device applications. Exposing a nanocrystal film to strong UV light allowed the oleic acid ligands on the surface of the nanocrystals to form an insoluble cross-linked network while the unexposed areas were still soluble to toluene solvent. Therefore, the UV light exposure through a shadow mask followed by solvent rinsing produced a small feature size on the order of 2 mu m. We also report that the integrated nanocrystal patterns in an organic light-emitting diode show clear electroluminescence from the nanocrystals.