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SURFACE SCIENCE APPROACH to ATOMIC LAYER DEPOSITION CHEMISTRY Amir Gharachorlou Purdue University

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SURFACE SCIENCE APPROACH to ATOMIC LAYER DEPOSITION CHEMISTRY Amir Gharachorlou Purdue University Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations January 2014 SURFACE SCIENCE APPROACH TO ATOMIC LAYER DEPOSITION CHEMISTRY Amir Gharachorlou Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Recommended Citation Gharachorlou, Amir, "SURFACE SCIENCE APPROACH TO ATOMIC LAYER DEPOSITION CHEMISTRY" (2014). Open Access Dissertations. 1077. https://docs.lib.purdue.edu/open_access_dissertations/1077 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. *UDGXDWH6FKRRO(7')RUP 5HYLVHG 01 14 PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance 7KLVLVWRFHUWLI\WKDWWKHWKHVLVGLVVHUWDWLRQSUHSDUHG %\ Amir Gharachorlou (QWLWOHG SURFACE SCIENCE APPROACH TO ATOMIC LAYER DEPOSITION CHEMISTRY Doctor of Philosophy )RUWKHGHJUHHRI ,VDSSURYHGE\WKHILQDOH[DPLQLQJFRPPLWWHH Fabio H. Ribeiro Dmitry Zemlyanov W. Nicholas Delgass Michael Harris To the best of my knowledge and as understood by the student in the Thesis/Dissertation Agreement, Publication Delay, and Certification/Disclaimer (Graduate School Form 32), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy on Integrity in Research” and the use of copyrighted material. Fabio H. Ribeiro $SSURYHGE\0DMRU3URIHVVRU V BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB $SSURYHGE\ John Morgan 08/19/2014 +HDGRIWKH Department *UDGXDWH3URJUDP 'DWH i SURFACE SCIENCE APPROACH TO ATOMIC LAYER DEPOSITION CHEMISTRY A Dissertation Submitted to the Faculty of Purdue University by Amir Gharachorlou In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2014 Purdue University West Lafayette, Indiana ii To my mom, Vaji and my family iii ACKNOWLEDGEMENTS I would like to acknowledge my advisor, Professor Fabio H. Ribeiro, and my mentor, Dr. Dmitry Zemlyanov. I am greatly indebted to the time they invested into me as a graduate student in the chemical engineering department. Looking back at my research quality, I can see a drastic improvement under Fabio’s supervision. Fabio’s expectations and standards have been always a great motivation for improving my research quality. Fabio has always helped me to understand the big picture in my research, and guided me in the right direction. Dima has always been available to answer all my questions with lots of bright ideas. I admire Dima’s attention to experimental details and his expertise in surface science characterization techniques. Dima has the unique ability to transfer his bright ideas from a simple sketch on paper to a fully functional and sophisticated experimental device. Through 4 years of working with him in the surface science lab I have been greatly inspired by his confidence and excitement for ultra-high vacuum and surface science research. I was blessed with having the best set of advisor and mentor for a Ph. D. student working on surface science characterization. I would also like to thank Professor W. Nicholas Delgass for his feedback and questions during our valuable meetings. I left every meeting with him with tons of new ideas. His graduate level courses in surface science characterization and heterogeneous catalysis are among the best courses I completed in graduate school. I would also like to thank the iv other member of my committee, Professor Mike Harris, for providing me with helpful feedback in my preliminary exam and dissertation. I acknowledge insight and help I received from Professor Ron Reifenberger on the STM portion of my work. He has been always a valuable part of our surface science research group with his expertise in UHV and STM techniques. Coming from a physics background, he brought a new perspective to our meetings that allowed us to improve our research quality and target a wider range of audiences. During my initial years in grad school I was gifted to work under the guidance of Dr. Anna Nartova from the Boreskov Institute of catalysis in Novosibirsk, Russia. Anna visited us twice as a visiting researcher, and her help in teaching me about ultra-high vacuum field and the surface science characterization field is highly appreciated. I would also like to thank Dr. David Taylor. He helped me with lots of electronic repairs and taught me the correct approach to troubleshooting. I would like to thank Dr. Xiangkui Gu and professor Jeff Greeley for their DFT calculations and collaboration with our experimental group which helped us answer complicated questions in our research. I would also like to express my gratitude to my current and past group and classmates: Harshavardhan Choudhari, Vinod Venkatakrishnan, Dr. Wen-Sheng Lee, Dhairya Mehta, Dr. Jorge H. Pazmino, Dr. Sara Yohe, Yanran Cui, John Degenstein, Mckay Easton, Anuj Verma, James Harris, Kaiwalya Sabnis, Atish Parekh, Fred Sollberger, Dr. Paul Dietrich, and Dr. Vincent Kaspersky. I would like to especially thank Dr. Bradley R. Fingland. Brad introduced me to surface science and UHV systems and taught me how to work with different surface science analysis techniques. I have learned a lot from him during v our short time together. Advice given by Dr. Andrew Smeltz has been a great help in understanding the surface science concepts and experiments during my starting period. I also want to thank Mike Detwiler, my lab mate whom has worked closely with me during the last 4 years. I was fortunate to have him by my side during our tough UHV experiments. His friendship and knowledge has been a valuable resource to me. I would also like to express my appreciation to Purdue Chemical Engineering and Birck Nanotechnology Center staff that assisted me during my grad school years. I am particularly grateful for the assistance given by Dr. Yury Zvinevich and Jeff Valley and Debra Bowman. I would also like to express great thanks to my roommate during the grad school years, Dr. Pooria Haghi, for our interesting discussions and fun times we had together. Finally, I wish to thank my parents for their support and encouragement throughout my study. Even if I was not able to see them during last 5 years I have always felt their love. I appreciate them for all I have achieved. I would also like to thank my brother Ali and my sister Afsaneh for their love and support. I also want to thank Ava Nassir who has been by my side during the last two years in grad school. She added new sets of goals to my life and her patience and support is highly appreciated. I could simply not ask for a better companion. I would also like to acknowledge the Department of Energy and the Institute for Atom- Efficient Chemical Transformations (IACT) for their financial support. vi TABLE OF CONTENTS Page LIST OF TABLES ............................................................................................................. ix LIST OF FIGURES ............................................................................................................ x ABSTRACT ............................................................................................................ xix CHAPTER 1. INTRODUCTION ................................................................................. 1 1.1 Atomic layer deposition (ALD) .................................................................1 1.1.1 ALD principles ....................................................................................3 1.2 ALD in catalysis .........................................................................................4 1.2.1 Metal nanoparticle deposition by ALD ...............................................4 1.2.2 Protecting metal nanoparticles by ALD ..............................................6 1.3 ALD characterization techniques ...............................................................9 1.3.1 Quartz crystal microbalance (QCM) ...................................................9 1.3.2 Quadrupole mass spectrometer (QMS) .............................................10 1.3.3 Fourier transform infrared spectroscopy (FTIR)...............................10 1.4 Surface science studies of ALD ...............................................................12 1.4.1 Surface science characterization of the ALD in literature ................13 1.4.1.1 X-ray photoelectron spectroscopy (XPS) ............................................ 13 1.4.1.2 Scanning tunneling microscopy (STM) ............................................... 16 1.5 Motivation ................................................................................................17 CHAPTER 2. EXPERIMENTAL............................................................................... 19 2.1 Preparation chamber and precursor dosing line .......................................19 2.1.1 Precursor safety precautions .............................................................20 2.2 Analysis chamber .....................................................................................22 2.3 STM tip preparation stage ........................................................................23 2.4 Ex-situ batch reactor .................................................................................26 vii Page 2.5 XPS coverage and thickness model derivation ........................................28 2.5.1 Derivation of non-attenuating overlayer model ................................29 2.5.2 XPS model for thickness, t, of uniform overlayer ............................30 CHAPTER 3. PALLADIUM NANOPARTICLE
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