3-D Integrated Electronic Microplate Platform for Low-Cost Repeatable Biosensing Applications

This paper presents a 3-D integrated disposable “electronic microplate” (e-microplate) platform that allows the reuse of CMOS biosensor, thereby significantly reducing cost and increasing throughput compared to nondisposable biosensing systems. The e-microplate utilizes mechanically flexible interconnects and through-silicon-vias to electrically connect the cells cultured on the top (sensing electrode side) of the e-microplate to the electrodes on the CMOS biosensor while maintaining a physical separation between the aforementioned substrate tiers. Electrical measurements performed show that the incorporation of the e-microplate does not degrade the sensing amplifier's gain, 3-dB bandwidth, or the input referred noise; this ensures a high signal-to-noise ratio allowing accurate sensing of weak signals from living cells under test. Cell growth experiments performed show adhesion and growth of mouse embryonic stem cells on the surface of the sensing electrodes of the e-microplate. Impedance mapping for Dulbecco's phosphate buffered saline solution performed with the e-microplate, for two different e-microplate assemblies, confirms the functional accuracy of the assembled systems.