Keywords
infrared, millimeter-wave, detector, antenna-coupled, fabrication
Abstract
Antenna-coupled detectors provide uncooled, cost-effective solutions for infrared and millimeter-wave imaging. This work describes the design, fabrication, measurement, and optimization of several types of antenna-coupled detectors for LWIR (8 - 12 µm) and 94 GHz radiation. Two types of millimeter-wave antenna-coupled detectors were fabricated and tested: a slot antenna coupled to a bolometer, and a patch antenna coupled to a SiC Schottky diode. Electromagnetic modeling of the antennas helped guide the design of antennas with better impedance matching to the detectors. Schottky diodes are discussed as detectors for millimeter-wave and infrared radiation, with the goal of increasing the cutoff frequency to allow infrared detection. The magnitude of response of antenna-coupled bolometric detectors to infrared radiation is affected by the thermal-conduction properties of the sensor structure. Two fabrication processes were developed to improve the thermal isolation of the antenna-coupled bolometer from its substrate. The first process creates a membrane beneath the device. Measured results show a factor of 100 increase in responsivity over an identical device without a membrane. The second process thermally isolates the device from its substrate by suspending the metallic structure in air. Several factors for optimization of infrared antenna-coupled detectors are investigated. The complex dielectric function of the metal from which the antenna is constructed can affect the performance of the device. The use of a ground plane and dielectric standoff layer beneath the antenna can increase the sensor responsivity. Dielectric material properties and thicknesses are considered, and incorporated in device simulations. Finally, a potential fabrication process is presented for via connections from the antenna-coupled detector through a ground plane to bond pads to mitigate the effect of bias lines on antenna behavior.
Notes
If this is your thesis or dissertation, and want to learn how to access it or for more information about readership statistics, contact us at STARS@ucf.edu
Graduation Date
2006
Semester
Summer
Advisor
Boreman, Glenn
Degree
Doctor of Philosophy (Ph.D.)
College
College of Optics and Photonics
Degree Program
Optics
Format
application/pdf
Identifier
CFE0001242
URL
http://purl.fcla.edu/fcla/etd/CFE0001242
Language
English
Length of Campus-only Access
None
Access Status
Doctoral Dissertation (Open Access)
STARS Citation
Middleton, Charles, "Antenna-coupled Infrared And Millimeter-wave Detectors: Fabrication, Measurement And Optimization" (2006). Electronic Theses and Dissertations. 920.
https://stars.library.ucf.edu/etd/920