Figure 2.
(a) Pictorial representation of the sensor’s cross-section. Floating-gate electrodes were fabricated in aluminum and patterned by means of photolithography. A hybrid-dielectric made of a thermally-growth Al2O3 layer and a Parylene C film allows low voltage device operation. Control-gate, source, and drain electrodes and the sensing area are made of gold and patterned by means of photolithography; (b) Picture of the device fabricated as described in materials and methods section. The insets show a magnification of the channel area.