Nanowire Sensor

Relying on nanotechnology fabrication, UC-Berkeley professor of electrical engineering Ali Javey led his research group to hybridize a photon sensor and a transistor circuit into a highly sensitive light detector that functions as a single pixel.  They accomplished this by lithographing light sensitive nanowires of cadmium selenide onto a silicon substrate; then, on another silicon substrate, they printed germanium nanowires of the transistor, and lastly attached electrodes.  In the resulting overlay, the light sensors convert photons into electrons, and the transistor circuit amplifies the signal up to five times. The trick in this is to get the two circuits correctly aligned.  Javey imagines this approach used in making “sensor tapes” that might be used for imaging or detecting chemical concentrations in, say, pathology slides.   MORE

Image Credit: Ali Javey and Technology Review