S/N Improvement of Nano-Cuboid Photodetector Using Combination of Small Device Area and Converging Lens

We report on an improvement of the signal to noise ratio (S/N) of a nano-cuboid photodetector using combination of small device area and converging lens. In order to measure infrared light efficiently with a Schottky photodetector, it is necessary to improve the S/N. For S/N increase, we proposed a combination of nano-cuboid array that can absorb wide-angle infrared light and converging lens. For noise reduction, the device area downsized to 1/100. As a result of the signal enhancement and the noise reduction together, the S/N was improved by about 20 dB. The combination of a small device area, an optical absorber and a convex lens worked effectively for measuring the near-infrared light.