Polarization Imaging Sensors in Advanced Feature CMOS Technologies

Author

Raphael Njoroge Njuguna, Washington University in St. Louis

Abstract

The scaling of CMOS technology, as predicted by Moore's law, has allowed for realization of high resolution imaging sensors and for the emergence of multi-mega-pixel imagers. Designing imaging sensors in advanced feature technologies poses many challenges especially since transistor models do not accurately portray their performance in these technologies. Furthermore, transistors fabricated in advanced feature technologies operate in a non-conventional mode known as velocity saturation. Traditionally, analog designers have been discouraged from designing circuits in this mode of operation due to the low gain properties in single transistor amplifiers. Nevertheless, velocity saturation will become even more prominent mode of operation as transistors continue to shrink and warrants careful design of circuits that can exploit this mode of operation.

In this research endeavor, I have utilized velocity saturation mode of operation in order to realize low noise imaging sensors. These imaging sensors incorporate low noise analog circuits at the focal plane in order to improve the signal to noise ratio and are fabricated in 0.18 micron technology. Furthermore, I have explored nanofabrication techniques for realizing metallic nanowires acting as polarization filters. These nanoscopic metallic wires are deposited on the surface of the CMOS imaging sensor in order to add polarization sensitivity to the CMOS imaging sensor. This hybrid sensor will serve as a test bed for exploring the next generation of low noise and highly sensitive polarization imaging sensors.

Committee Chair

Viktor Gruev

Committee Members

James Buckley, Roger Chamberlain, Patrick Crowley, Barani Raman, William Richard

Comments

Permanent URL: https://doi.org/10.7936/K7MG7MZ9

Degree

Doctor of Philosophy (PhD)

Author's Department

Computer Science & Engineering

Author's School

McKelvey School of Engineering

Document Type

Dissertation

Date of Award

Summer 8-15-2013

Language

English (en)

DOI

https://doi.org/10.7936/K7MG7MZ9

Recommended Citation

Njuguna, Raphael Njoroge, "Polarization Imaging Sensors in Advanced Feature CMOS Technologies" (2013). McKelvey School of Engineering Theses & Dissertations. 220.

The definitive version is available at https://doi.org/10.7936/K7MG7MZ9