Antimonide-based Backward Diode Millimeter-Wave Detectors
Tech ID: 08-047
Inventor: Dr. Patrick Fay
Date added: June 19, 2020
A novel low-noise signal detector in the millimeter wave spectrum that has high sensitivity, a high curvature coefficient, low resistance, and low capacitance.
The unique propagation characteristics of millimeter waves, including the ability to penetrate obstacles like fog, dust, fabric, and light building materials make them an ideal candidate for detection, imaging, and remote sensing under adverse conditions. Technologies for millimeter-wave detection have been extensively explored in recent years for applications in navigation, avionics, security screening, and chemical sensing. Some devices currently employed to detect millimeter-wave signals include Schottky diodes as direct square-law detectors. However, to achieve a sufficiently low junction resistance for high-efficiency impedance matching at millimeter-wave frequencies, Schottky diodes are typically biased and/or implemented in conjunction with one or more amplifiers in an effort to minimize detection noise. In some instances that demand a low noise floor, multiple stages of pre-amplifiers are necessary, each currently having a cost in the thousands of dollars. Ultimately, improving the performance of passive millimeter-wave and submillimeter-wave imaging systems requires high curvature, low, capacitance, and modest junction resistance to produce low noise detectors.
Researchers at the University of Notre Dame developed a heterostructure design for low noise detectors. The diode has a specific non-uniform doping profile that leads to measurable benefits over uniform doping structures: increased zero-bias sensitivity, a low noise equivalent power (NEP), low junction capacitance, low junction resistance, high curvature coefficient, effectiveness at higher frequencies. The Antimonide-based Backward Diode Millimeter-Wave Detectors developed by the University of Notre Dame is a better alternative than Schottky diodes as direct millimeter wave detectors and is a promising design for improving performance of low-noise millimeter-wave and submillimeter-wave detectors in passive imaging applications.
• High sensitivity
• High curvature coefficient > 47 V-1
• Low junction resistance for low noise
• Low capacitance for high speed; reduced by ≥ 24%
• Low NEP ≤ 0.18 pW/Hz1/2
• Promising candidate for passive image sensors at room temperature without RF preamplification
• Potential for operation through Y band and beyond
US 8,592,859 B2
Sb-heterostructure Millimeter-Wave Detectors with Improved Noise Performance
Sub-Micron Area Heterojunction Backward Diode Millimeter-Wave Detectors With 0.18 pW/Hz1/2 Noise Equivalent Power
Technology Readiness Level
TRL 3 - Experimental Proof of Concept