Integration of diamond microelectrodes on CMOS-based amperometric biosensor array by film transfer technology

This paper reports a complementary metal oxide semiconductor (CMOS)-based 20×20 amperometric biosensor array using boron-doped diamond (BDD) microelectrodes with excellent electrochemical properties. The BDD electrodes were once formed on a Si wafer at 800°C, and then transferred to a 0.18 μm CMOS wafer with a benzocyclobutene (BCB) bonding interlayer. As a result, the BDD microelectrodes were arrayed without damage in the CMOS LSI circuit. The fully-integrated device could detect histamine and dopamine owing to a wide potential window of the BDD electrode, and offered 2-dimensional real-time imaging of histamine diffusion in a solution.