An extended floating gate gas sensor using polypyrrole as a sensing polymer

A novel charge sensitive sensor platform using a basic floating gate MOS (FGMOS) transistor has been developed. In this new design, the top metal layer of a standard CMOS process has been used as an extended sensor pad which is connected to the floating gate. A charge sensitive conducting polymer has been used to measure different gas analytes. This FGMOS sensor significantly reduces the number of post processing steps required and makes this design compatible with VLSI integration. A 2D sensor array can be fabricated using this type of design and since it is compatible with standard CMOS fabrication processing, the required array circuitry can be included.