Improved Adhesion of Gold Thin Films Evaporated on Polymer Resin: Applications for Sensing Surfaces and MEMS

Sensors

Behrang Moazzez¹  Stacey M. Oɻrien¹ 

[1] Department of Chemistry, Memorial University, St. John's, NL A1B3X7, Canada;

关键词: thin films;    adhesion;    elastic modulus;    roughness;    biomedical cantilever sensors;    microfluidic sensors;    SU-8;    metal;    gold;   

DOI  :  10.3390/s130607021

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.