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Large Area Conformal Infrared Frequency Selective Surfaces University of Central Florida STARS Electronic Theses and Dissertations, 2004-2019 2014 Large Area Conformal Infrared Frequency Selective Surfaces Jeffrey D'Archangel University of Central Florida Part of the Electromagnetics and Photonics Commons, and the Optics Commons Find similar works at: https://stars.library.ucf.edu/etd University of Central Florida Libraries http://library.ucf.edu This Doctoral Dissertation (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Electronic Theses and Dissertations, 2004-2019 by an authorized administrator of STARS. For more information, please contact [email protected]. STARS Citation D'Archangel, Jeffrey, "Large Area Conformal Infrared Frequency Selective Surfaces" (2014). Electronic Theses and Dissertations, 2004-2019. 4777. https://stars.library.ucf.edu/etd/4777 LARGE AREA, CONFORMAL INFRARED FREQUENCY SELECTIVE SURFACES by JEFFREY ALLEN D’ ARCHANGEL B.S. Saginaw Valley State University, 2009 M.S. University of Central Florida, 2011 A dissertation submitted in partial fulfillment of the requirement for the degree of Doctor of Philosophy in the College of Optics and Photonics: CREOL & FPCE at the University of Central Florida Orlando, Florida Fall Term 2014 Major Professor: Glenn D. Boreman © 2014 Jeffrey Allen D’ Archangel ii ABSTRACT Frequency selective surfaces (FSS) were originally developed for electromagnetic filtering applications at microwave frequencies. Electron-beam lithography has enabled the extension of FSS to infrared frequencies; however, these techniques create sample sizes that are seldom appropriate for real world applications due to the size and rigidity of the substrate. A new method of fabricating large area conformal infrared FSS is introduced, which involves releasing miniature FSS arrays from a substrate for implementation in a coating. A selective etching process is proposed and executed to create FSS particles from crossed-dipole and square-loop FSS arrays. When the fill-factor of the particles in the measurement area is accounted for, the spectral properties of the FSS flakes are similar to the full array from which they were created. As a step toward scalability of the process, a square-patch design is presented and formed into FSS flakes with geometry within the capability of ultraviolet optical lithography. Square-loop infrared FSS designs are investigated both in quasi-infinite arrays and in truncated sub-arrays. First, scattering-scanning near-field optical microscopy (s-SNOM) is introduced as a characterization method for square-loop arrays, and the near-field amplitude and phase results are discussed in terms of the resonant behavior observed in far-field measurements. Since the creation of FSS particles toward a large area coating inherently truncates the arrays, array truncation effects are investigated for square-loop arrays both in the near- and far-field. As an extension of the truncation study, small geometric changes in the design of square-loop arrays are introduced as a method to tune the resonant far-field wavelength back to that of the quasi- infinite arrays. iii To my children, Heaven and Maxwell. iv ACKNOWLEDGMENTS My tenure as a doctoral student and candidate has been quite rewarding under the leadership of Dr. Glenn Boreman. I am grateful for his mentorship as well as his compassion during a few difficult personal times. I appreciate that Dr. Winston Schoenfeld agreed to chair my dissertation committee and also acknowledge that his laboratory class in clean room fabrication was a significant help in my research. I also acknowledge the rest of my dissertation committee, Dr. Patrick LiKamWa, Dr. Pieter Kik, and Dr. Brian Lail for stimulating discussions concerning my work as well as other research topics. I am thankful for the guidance and camaraderie of past and current members of our research group, the Infrared Systems Laboratory. For their efforts to bring me up to speed on various fabrication processes, simulations, and characterization methods, I thank Dr. Jeffrey Bean, Dr. Brian Slovick, Lt. Col. Louis Florence, Alex Dillard, Dr. Peter Krenz, Dr. David Shelton, Dr. James Ginn, Dr. Samuel Wadsworth, and Dr. Ed Kinzel. For their helpful discussions and critical contributions to my work, I thank Dr. Eric Tucker and Robert Brown. My background in Electromagnetics and Mathematics upon entering graduate school has been significant toward success in the academic hurdles of my doctoral program. Foremost, I acknowledge Dr. Hsuan “Frank” Chen at Saginaw Valley State University for his tutelage in Optics; his lectures and experimental training have been instrumental in my academic achievements. There are several other Professors at Saginaw Valley State University as well as Delta College whom I thank for their contributions to my understanding of the subjects relating v to Optics: these are Dr. Marian Shih and Dr. Michael Faleski in Physics, Dr. Jonathan Leonard in Electrical Engineering, Prof. David Redman in Mathematics, and Prof. Hideki Kihata in Photography. As an undergraduate student, I spent over two years working in Research and Development at the Dow Chemical Company, which left me well-prepared for the thin film fabrication and characterization that would take place in my graduate research. I am forever indebted to Dr. Mark Bernius for creating this opportunity, and also for strengthening my research skills by allowing me to take the lead on several optical sensing projects. Additionally, I thank Dr. Melissa Mushrush, Dr. Rebekah Feist, Doug Wirsing, Jeff Mitchell, Dr. Simon Yeung, Dr. Buford Lemon, Bob Haley, Dr. Beth Nichols, Dr. Jennifer Gerbi, Dr. Joseph George, Dr. Rentian Xiong, and Emily Hill for their friendship, assistance with learning fabrication and characterization techniques, and advice concerning graduate school during my time at Dow. In 2011, I was awarded the SMART Scholarship, which is funded by the United States Department of Defense and administered by the American Society for Engineering Education. I wholeheartedly thank all who were involved in choosing me for this prestigious honor. In particular, I am grateful to Dr. Jose Colon who saw my potential as a government scientist and initially acted as my mentor in the program. In 2012, I moved to the University of North Carolina at Charlotte to continue my research in the Infrared Systems Laboratory, while remaining a student in the CREOL program at the University of Central Florida. The technical and administrative staff in Charlotte has treated me like one of their own students, and I am quite grateful for this. In particular, kind assistance from Scott Williams, Erik LaRuffa, Dr. Lou Deguzman, Dr. Robert Hudgins, and Mark Clayton is vi acknowledged. Back at the University of Central Florida, I would like to thank several people who helped with my continuity as a CREOL student; these include Rachel Franzetta, Matthew Petrone, Dr. Winston Schoenfeld, and Dr. David Hagan. Additionally, I express my gratitude to the SMART Program Office for being understanding of the necessity for my relocation. Ten years ago, I was a pizza delivery guy without much prospect of ever becoming anything else. I thank God for bringing direction to my life. I express gratitude to the only two people who supported and believed in me back then, when I had the random and crazy idea to go back to college: my wife Brandi and my grandmother Ruth. Finally, with all my being, I recognize the hard work, patience, and unconditional love of my wife over the past five years. Without her efforts, none of my accomplishments would have been even remotely possible. I acknowledge the fact that she has unselfishly put many of her wants and aspirations aside such that I may focus on advancing my career. I look forward to returning the favor. vii TABLE OF CONTENTS LIST OF FIGURES ....................................................................................................................... xi LIST OF ACRONYMS ............................................................................................................... xvi CHAPTER ONE: INTRODUCTION ............................................................................................. 1 1.1 Introduction to Frequency Selective Surfaces .......................................................... 2 1.2 Frequency Selective Surfaces at Infrared ................................................................. 6 1.3 Motivation for Large Area, Conformal Infrared Frequency Selective Surfaces ...... 7 1.4 Prior Publication Disclosure ..................................................................................... 9 CHAPTER TWO: RESEARCH APPROACH ............................................................................. 10 2.1 Design and Simulation ............................................................................................ 11 2.2 Fabrication .............................................................................................................. 17 2.2.1 Lithographic Processes .................................................................................... 18 2.2.2 Thin Film Deposition ....................................................................................... 21 2.2.3 Etching ............................................................................................................. 25 2.3 Characterization ...................................................................................................... 26 2.3.1 Material Characterization by Ellipsometry
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