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Enabling High Performance III-V Thin-Film Photodetectors on Unconventional Surfaces

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Enabling High Performance III-V Thin-Film Photodetectors on Unconventional Surfaces Enabling High Performance III-V Thin-Film Photodetectors on Unconventional Surfaces by Dejiu Fan A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Electrical Engineering) in the University of Michigan 2020 Doctoral Committee: Professor Stephen Forrest, Chair Assistant Professor Andrej Lenert Professor Wei Lu Professor Zetian Mi Dejiu Fan [email protected] ORCID iD: 0000-0002-7374-134X © Dejiu Fan 2020 DEDICATION To a better world ii ACKNOWLEDGEMENTS The work presented in this thesis could not have been accomplished without the contributions of many others. First, I would like to express my most sincere gratitude to my advisor, Professor Stephen Forrest, for his mentorship during these years. I started as an undergraduate student in his OCM group in 2012. His passion and enthusiasm toward science and engineering inspired me to begin my Ph.D. career in September, 2013. During this six-and-half-year journey, he has shown exceptional patience to my million failures, and always guided me to the positive path with his deep insight and great relish of scientific research. His incentive mentoring of “Seek and You Shall Find” has promoted me to become a critical thinker and a qualified researcher. The most important lesson I learned is that the horizon of research is beyond publishing papers and earning a degree; the ultimate accomplishment is to make a better world. Next, I would like to thank all my mentors and collaborators. Jeramy Zimmerman was my first mentor when I joined the group and I appreciate his great help when instructing me on solution process techniques and organic deposition equipment. I would like to thank Kyusang Lee for being a supportive mentor who introduced me to the growth of III-V materials using MBE and basic inorganic fabrication techniques. I would also like to thank my mentee Byungjun Lee who has collaborated with me on almost all the projects that I have worked on and helped me a great amount on device fabrication and machine maintenance. I am also thankful for the collaboration with Caleb Coburn on hemispherical FPA and organic CCD, Tobias Burger, Sean McSherry, and Andrej Lenert on multiple TPV projects, Xiaozhou Che on multijunction OPV, Xiao Liu on Organic/2D iii heterojunction, Xiaheng Huang on ultra-thin OLED, and Xinjing Huang on solution-processed tandem OPV. I am also grateful to have overlap with many other OCM group members with whom I have spent a lot of enjoyable time, including Greg McGraw, Brian Lassiter, Nana Wang, Kyle Renshaw, Cedric Rolin, Yifan Zhang, Xiaoran Tong, Michael Slootsky, Xiaomi Zhang, Kevin Bergemann, Xin Xiao, Olga Griffith, Ardavan Oskooi, Qi Wang, Jaesang Lee, Anurag Panda, Quinn Burlingame, Yue Qu, Claire Arneson, Kan Ding, Jeffrey Horowitz, Jongchan Kim, Boning Qu, Hafiz Sheriff, Yongxi Li, and Shaocong Hou. Especially, I would like to thank Eva for being supportive and attentive on the administration and logistics. I would also like to acknowledge many of the LNF staff for being great help including Pilar, Dennis, Sandrine, Matt, Brian, Shawn, Kevin, Vishva, etc. In addition, many thanks to my friends Muzhi Wang, Yue Zheng, Tianhua Zhang, Yixing Lu, Fuxi Cai, Shaopin Song, and many others for spending joyful times with me outside the lab. Finally, I would like to thank my parents and girlfriend for their eternal love and care that encourage me to walk through tough moments during these years. I have been feeling the confidence of “You’ll Never Walk Alone” with their company and support they have given me along the way and till the end of this journey. Dejiu Fan Ann Arbor, MI March, 2020 iv TABLE OF CONTENTS DEDICATION ......................................................................................................... ii ACKNOWLEDGEMENTS .................................................................................. iii LIST OF TABLES ............................................................................................... viii LIST OF FIGURES ............................................................................................... ix ABSTRACT .......................................................................................................... xiii Chapter 1 Introduction ............................................................................................ 1 1.1. Thesis Overview .......................................................................................................... 1 1.2. Overview of III-V Compound Semiconductors ........................................................... 3 1.2.1. Crystalline Structure of Compound Semiconductors ....................................... 3 1.2.2. Epitaxial Growth ............................................................................................... 6 1.3. Optoelectronic Devices ................................................................................................ 8 1.3.1. LED and Laser .................................................................................................. 9 1.3.2. Photodetector .................................................................................................. 10 1.3.2.1. Light Detection .................................................................................... 10 1.3.2.2. Energy Harvesting ............................................................................... 12 1.4. Device Fabrication ..................................................................................................... 15 1.4.1. Lithography ..................................................................................................... 15 1.4.2. Metal Patterning .............................................................................................. 16 1.4.3. Etching ............................................................................................................ 17 Chapter 2 Thin Film Technologies and Non-Planar Architectures ..................21 2.1. Thin-Film Optoelectronics ......................................................................................... 22 2.1.1. Mechanical Spalling........................................................................................ 23 2.1.2. Epitaxial Lift-Off ............................................................................................ 24 v 2.1.3. Laser Lift-Off .................................................................................................. 26 2.1.4. 2D Material-Assisted Lift-Off ........................................................................ 27 2.2. Non-Planar Architectures ........................................................................................... 28 2.2.1. Developable vs. Non-Developable Surfaces ................................................... 29 2.2.2. Methods for Deformation ............................................................................... 31 2.2.2.1. Rolling.................................................................................................. 31 2.2.2.2. Folding ................................................................................................. 32 2.2.2.3. Curving ................................................................................................ 33 2.2.2.4. Buckling ............................................................................................... 34 2.2.3. Bio-Inspired Artificial Imaging Systems ........................................................ 35 2.2.3.1. Compound Eye Type Imaging Systems ............................................... 36 2.2.3.2. Single-Chambered Eye Type Imaging Systems .................................. 38 2.3. Summary .................................................................................................................... 40 Chapter 3 A Flexible Thin-Film InGaAs Photodiode Focal Plane Array ........47 3.1. Introduction ................................................................................................................ 47 3.2. Photodiode Focal Plane Array Fabrication ................................................................ 49 3.3. Photodiode Characterization ...................................................................................... 54 3.4. Array Yield and Reliability ........................................................................................ 57 3.5. Application 1: 2π Imager ........................................................................................... 60 3.6. Application 2: High Resolution Spectroscopy ........................................................... 63 3.7. Conclusion ................................................................................................................. 70 Chapter 4 A Retina-Like Hemispherical Focal Plane Array ............................75 4.1. Introduction ................................................................................................................ 76 4.2. Hemispherical Focal Plane Array (HFPA) Fabrication ............................................. 78 4.3. Device characterization .............................................................................................. 87 4.4. Imaging with HFPA ................................................................................................... 91 4.5. Conclusion ................................................................................................................. 96 vi Chapter 5 Thin-Film Architectures with High Spectral Selectivity for Thermophotovoltaic
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