%0 Journal Article
%T Improved Adhesion of Gold Thin Films Evaporated on Polymer Resin: Applications for Sensing Surfaces and MEMS
%A Behrang Moazzez
%A Stacey M. O'Brien
%A Erika F. Merschrod S.
%J Sensors
%D 2013
%I MDPI AG
%R 10.3390/s130607021
%X We present and analyze a method to improve the morphology and mechanical properties of gold thin films for use in optical sensors or other settings where good adhesion of gold to a substrate is of importance and where controlled topography/roughness is key. To improve the adhesion of thermally evaporated gold thin films, we introduce a gold deposition step on SU-8 photoresist prior to UV exposure but after the pre-bake step of SU-8 processing. Shrinkage and distribution of residual stresses, which occur during cross-linking of the SU-8 polymer layer in the post-exposure baking step, are responsible for the higher adhesion of the top gold film to the post-deposition cured SU-8 sublayer. The SU-8 underlayer can also be used to tune the resulting gold film morphology. Our promoter-free protocol is easily integrated with existing sensor microfabrication processes.
%K thin films
%K adhesion
%K elastic modulus
%K roughness
%K biomedical cantilever sensors
%K microfluidic sensors
%K SU-8
%K metal
%K gold
%U http://www.mdpi.com/1424-8220/13/6/7021