Detection of Infrared Radiation using Semiconductor Nanostructures

The goal of this investigation is demonstration of a new class of extremely sensitive detectors of infraRed (IR) radiation. As is well known, conventional detector materials are near the limit of sensitivity and hence spectacular improvements are not expected. In the last few years there have been tremendous advances in the fabrication of silicon nanostructures and arrays of carbon nanotubes. There has also been progress in the theory of single-electron effects, and other electrical and optical properties of nanoscale mosfets. Now over the last forty years, the majority of IR photon detectors have been based on using some type of transition across a bandgap, or transition between energy levels, in a semiconductor. In this project we depart from that tradition and propose the use of silicon nanostructures to detect IR radiation. In phase I, the mechanism for IR detection, a preliminary design and analysis of the device, as well as the method of fabrication were specified. In phase II the main goal is the fabrication of the individual detector, and arrays of detectors. A more detailed analysis of the signal-to-noise ratio and detectivity will also be presented. The detailed analysis would aid optimization of the design and clarify the limits of this new method of detection.