Surface plasmon resonance (SPR) sensing technique which provides high
specificity and accuracy has been an important method for molecular
sensing technology. In the past, in order to affix 45 nm gold film onto
glass or silicon substrate, several nanometers of chromium (Cr) or
titanium (Ti) has been used as adhesive layer for the attachment of Au
film. However, the existence of Cr or Ti thin film deteriorates the
performance of SPR sensor due to their characteristic optical absorption.
Our experimental results have confirmed the uses of conducting metal
oxide, specifically, ITO and Zinc Oxide (ZnO) can be used to replace Cr
or Ti for better performance in terms of SPR resonant properties
(resonant angle and HMBW) and sensitivity enhancement for 3 to 15 times
than traditional ones. It would contribute significantly to the SPR
applications in both biosensors and gas sensors.