Fabrication of 20nm period multilayer metal-dielectric structures and initial patterning tests

The use of noble metals within nanophotonics and nanoplasmonics in general is a well established practice. However, when the thickness of the metals used, in particular gold, decreases, their quality suffers. In particular, the influence of the adhesion layers becomes significant. In this papers we present our approach towards obtaining up to 10 periods of gold/alumina layers, with 20nm period and 50% filling fraction.

Using organic adhesion layers, the Au behaves very close to the theoretical limit, demonstrating that these layers minimally influence the Au properties. Initial attempts into patterning these multi-layer structures show the possibility of obtaining simple one-dimensional designs having down to ca. 100nm linewidth.

Results and challenges in using our approach are also presented.