2. Manufacturing principle

As shown in figure 1 , the sensors described below are based on bundles of up to 100 nanowires. These beams are prepared by decorating the steps present on the surface of HOPG graphite, as shown opposite. This is a layered material whose crystalline grains, 50 to 500 µm in diameter, are all oriented in the same direction, perpendicular to the layered plane. At grain surfaces and grain boundaries, the main defects are steps formed by incomplete graphite sheets. On the surface of a single grain, there may be several hundred of these steps, approximately linear and parallel, and spaced 0.5 to 5 µm apart. The decoration of the...