I-Corps: Silicon Terahertz Electronics

Rensselaer Polytechnic Institute, Troy NY

Investigators

Abstract

This project is to test the feasibility of nanoscale FET antenna arrays with elements of new, previously unexplored configurations for THz radiation interaction with objects. This work will be based on prior NSF-supported research that demonstrated unique Si THz MOSFET and FINFET detectors. The current approach will take advantage of inexpensive readout and image processing electronics based on commercial Si VLSI technology. The project will result in the fabrication of new nanoscale FET elements forming the THz detection units with antenna. Design and simulation of antennas has been performed in HFSS to ensure maximum efficiency. A major challenge of determining device impedance to reduce reflection and maximize antenna gain has been resolved using software tools developed by the PI group. The project will include studies of the THz interaction with the device and coupling to antenna structures and analysis of sensitivity, gain, noise, temperature dependencies, and Noise Equivalent Power. The PI group will later combine individual Si THz detectors into large arrays to form Focal Plane Arrays (FPA) for THz imaging. The broader impact of terahertz systems to be developed in this program is in the areas of national security, medical imaging, manufacturing, communication, and spectroscopy. Today's terahertz detectors are hampered by high cost, low responsivity at room temperature, high noise, and limited speed. The airport security industry has grown to be over $130 billion per year. One of the most widely used and effective airport security tools are the body scanner, which are typically X-ray based, posing substantial health risks, especially to frequent travelers. These systems suffer from relatively low resolution causing many false-positive detections. In comparison, THz technology is safe and effective for airport security. THz imaging can provide high resolution images and irradiates the subject with a fraction of the energy of X-rays, thus being a much safer solution. THz radiation cannot penetrate metal and detects plastic, making it a prime candidate for detecting hidden weapons. It can also be used to detect explosives, toxins, and other potential security threats. The proposed detectors could establish a new generation of THz systems which would exploit these unique opportunities.