Toward Fully Integrated CMOS Based Capacitive Sensor for Lab-on-Chip Applications

In this paper, we present a hybrid capacitive sensor featuring a 0.18mum CMOS integrated circuit incorporated with a microfluidic channel and a polyelectrolyte sensing layer (PSL). We describe the formation of ultrathin PSL atop a microfabricated gold electrode (MGE) and CMOS sensor, and thereafter demonstrate the viability of this new approach for Lab- on-Chip (LoC) applications. A direct-write fabrication process (DWFP) is also employed to create microchannel above CMOS chip in order to direct chitosan and alginate solutions toward the electrodes and form an on- chip PSL for detection purposes.