Nanopatterned Electrically Conductive Films of Semiconductor Nanocrystals

• Main Authors: Mentzel, Tamar (Contributor), Wanger, Darcy Deborah (Contributor), Ray, Nirat (Contributor), Walker, Brian J. (Contributor), Strasfeld, David B. (Contributor), Bawendi, Moungi G. (Contributor), Kastner, Marc (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Chemistry (Contributor), Massachusetts Institute of Technology. Department of Physics (Contributor)
• Format: Article
• Language: English
• Published: American Chemical Society, 2013-08-05T19:45:09Z.
• Subjects: Article
• Online Access: Get fulltext

 We present the first semiconductor nanocrystal films of nanoscale dimensions that are electrically conductive and crack-free. These films make it possible to study the electrical properties intrinsic to the nanocrystals unimpeded by defects such as cracking and clustering that typically exist in larger-scale films. We find that the electrical conductivity of the nanoscale films is 180 times higher than that of drop-cast, microscopic films made of the same type of nanocrystal. Our technique for forming the nanoscale films is based on electron-beam lithography and a lift-off process. The patterns have dimensions as small as 30 nm and are positioned on a surface with 30 nm precision. The method is flexible in the choice of nanocrystal core-shell materials and ligands. We demonstrate patterns with PbS, PbSe, and CdSe cores and Zn[subscript 0.5]Cd[subscript 0.5]Se-Zn[subscript 0.5]Cd[subscript 0.5]S core-shell nanocrystals with a variety of ligands. We achieve unprecedented versatility in integrating semiconductor nanocrystal films into device structures both for studying the intrinsic electrical properties of the nanocrystals and for nanoscale optoelectronic applications.