FIG. 1.

The design of the FET-based microfluidic chip. (a) Schematic diagram of the microfluidic chip. It consisted of six open chambers, six normally closed microvalves, and a micromixer/micropump. (b) Exploded view of the microfluidic chip, which was composed of five layers, including an air control layer (thick PDMS layer), a liquid channel layer (thin PDMS layer), a double-side tape, a FET device, and a PCB layer. The double-side tape was used for bonding PDMS layers and the PCB layer. (c) A photograph of the FET-based microfluidic chip. The dimensions of the chip were measured to be 25.0 mm × 35.0 mm × 4.9 mm. The red color indicates the air control layer and the blue color indicates the liquid channel layer. (d) The top-view and a photograph of the FET and the sensing region.