VLSI MAGIC layout of a chemfet fluid sensor; the sensor is at the
upper right of the lower left middle (bridge) circuit with various
levels of the sensor for testing at the lower right and left;
the fluid acts as the dielectric in a PMOS transistor for
which the oxide is etched out using the holes cut in the
gate. Other components are a neural type cell (middle right) for
making a smart sensor, a differential pair (top left) for
amplification and interfacing, and a ring oscillator (top right)
for self-test.
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