Lithographic Patterning and Selective Functionalization of Metal Nanoparticle Composite Films
Due to their tunneling-based charge transport mechanism, gold nanoparticle (GNP) composites attract significant interest for applications as resistive sensors for strain and volatile organic compounds. Here, we present a facile method for patterning and re-functionalization of alkanedithiol cross-linked GNP thin films based on deep ultraviolet photolithography. A lift-off process using a sacrificial layer of polymethyl methacrylate (PMMA) was used in combination with a rapid, spin-coating-based GNP film deposition procedure to fabricate patterned GNP films. Furthermore, PMMA mask layers were utilized for selective molecular doping of individual GNP film chemiresistors in a chemiresistor array with different ligand molecules, leading to altered chemical selectivities. The methods presented in this work are suitable for patterning organically cross-linked GNP films for various sensing applications as well as the fabrication of electronic noses based on GNP film chemiresistor arrays. Due to the photolithographic approach, the deposition and re-functionalization methods outlined in this paper are easily scalable, in contrast to serial techniques such as ink-jet printing or microdispensing.
Fraunhofer Center for Applied Nanotechnology CAN, Grindelallee 117, 20146 Hamburg, Germany
Bittinger, Sophia Caroline
Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany