We present a sophisticated method for the packaging of a micro-electro-mechanical biochip, which leaves the sensitive
surface area of the chip uncovered to allow for direct contact to aqueous environment. Together with adequate
integration in a fluidic cartridge, the packaging method allows for the realization of a lab-on-chip (LOC). A fluidic
interface to the cartridge is provided as well as electrical interfaces to the biochip electronics located in a readout
instrument. The biochip features a central membrane and electrodes, both located in the central chip area, and bond pads
distributed along the rim of the chip. The packaging method ensures a hermetic separation between the membrane
sensing area interfaced to liquids and the bond pad area. Challenging was the fact that both, the freely moving membrane
and the bond pads for electrical interconnection are positioned very close to each other on the same chip surface area.
We mounted the biochip into a recess of a rigid printed circuit board and electrically connected it to the latter with a
proprietary MicroFlex Interconnection (MFI) technology. A customized coating method using a specially shaped silicone
casting-mold ensured a very thin, hermetic encapsulation, which left the membrane safe and freely accessible.
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