Microfluidic-packaged CMOS chemiresistor detector for micro-scale gas chromatograph

The implementation of a microfluidic ‘detector cell’ is presented, which integrates a nanofabricated chemiresistor (CR) array with monolithic CMOS baseline cancellation circuitry and a microfluidic chamber for use in a micro-scale gas chromatograph (mGC). A robust packaging method was developed to facilitate a microfluidic interface between the detector cell and external mGC components while also reducing dead volume and the sorbence of sample vapours. The efficacy of the integrated detector cell was elucidated by consistent chip responses taken from a 4 × 2 CR array fabricated on the silicon dioxide surface of a custom-designed CMOS readout chip.