Comparison of Micro- and Nano-Pore Platinum Working Electrodes for CMOS Integrated Nondisposable Biosensor Applications

In this paper, micro-pore and nano-pore platinum (Pt) electrodes are fabricated, characterized, and compared in order to check the effects of the pore sizes of the working electrode in the electrochemical analysis. These electrodes are also fabricated on silicon substrate for developing nondisposable and continuous monitoring biosensors fully integrated with a CMOS read out circuit. The micro-pore Pt electrode was fabricated by using micromachining technique. The nano-pore Pt electrode was fabricated by using a nonionic surfactant C ₁₆EO₈ (octaethylene glycol monohexadecyl ether) and an electrodeposition technique. The micro-pore array Pt electrode has approximately 10 mum in pore diameter and 80 mum in height, while the nano-pore array Pt electrode has approximately 2.5 nm in diameter. The measured current responses of the fabricated nano-pore, micro-pore, and plane Pt electrodes are approximately 4600 nA/mm² , 92.4 nA/mm², and 9.9 nA/mm² in 0.1 M phosphate buffered saline solution mixed with 10 mM glucose solution, respectively