Plasmonic Films Can Easily Be Better: Rules and Recipes

High-quality materials are critical
for advances in plasmonics,
especially as researchers now investigate quantum effects at the limit
of single surface plasmons or exploit ultraviolet- or CMOS-compatible
metals such as aluminum or copper. Unfortunately, due to inexperience
with deposition methods, many plasmonics researchers deposit metals
under the wrong conditions, severely limiting performance unnecessarily.
This is then compounded as others follow their published procedures.
In this perspective, we describe simple rules collected from the surface-science
literature that allow high-quality plasmonic films of aluminum, copper,
gold, and silver to be easily deposited with commonly available equipment
(a thermal evaporator). Recipes are also provided so that films with
optimal optical properties can be routinely obtained.