pH Micro-sensors Associated With Micro-fluidics For Chemical Analysis

For water monitoring or many chemical or biological applications, pH measurements are very important, and especially the detection of a small pH changes. Such applications require the development of microsystems that present high sensitivity to pH, have a simple use, a low cost and a small size. This present pH sensor is a highly sensitive Suspended Gate Field Effect Transistors (SGFET) interfaced with PDMS microfluidic channels. This microsystem allows the transport and the testing of the liquid. The compatibility of the two technologies is checked by controlling and optimizing the sticking between PDMS and the surface of the sensor, the good electrical insulation, the control of the sensor electrical behavior after sticking. Preliminary tests have validated the possibility of detecting the presence of liquids flowing through microchannels. These micro-chambers can be used for specific biological phenomena inducing these changes in pH (enzymes, cells)