In this work we propose an alternative method for the fabrication of metal micro/nanostructures from metal-polymer nanocomposite resists and their subsequent electroless metallization. The process consists of three simple steps: 1. Fabrication of micro or nanopatterns by lithography or any other direct printing technologies (inkjet or microplotter printing...), 2. In-situ synthesis of metal nanoparticle during a post-bake step and 3. Non-electrochemical metallization of nanocomposite patterns. The novelty of our approach is that both Ag and Au nanoparticles are embedded into the polymer pattern and act as seeds for the reduction of Ag(I) when immersed into a solution of the corresponding precursor metal salt (AgNO₃) and an appropriate reducing agent. The key point of this procedure is the use of a weak reducing agent so that the metal reduction selectively takes place on the surface of the already formed nanoparticles, but not in the bulk of the growing solution. As a result, metal nanoparticles grow significantly into the nanocomposite structure until the micro/nanopattern is completely metallized. The growth of nanoparticles and the subsequent pattern metallization occur within a few hours. The metallization process was followed by UV-Vis spectroscopy, SEM and TEM for different reaction times. We also carried out the electrical characterization of the layers and confirmed that bulk conductivities of silver were achieved. Given that the progress of plasmonics is closely related to the advancement of material research and fabrication technology, we believe that this fabrication method may be very useful for the fabrication of devices profiting of SP and SPP optics (sensing, photovoltaics, optoelectronics…).

Date Published: 29 March 2013
PDF: 8 pages
Proc. SPIE 8682, Advances in Resist Materials and Processing Technology XXX, 86820X (29 March 2013); doi: 10.1117/12.2011555

Published in SPIE Proceedings Vol. 8682:
Advances in Resist Materials and Processing Technology XXX
Mark H. Somervell, Editor(s)