Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1999 Plasma Enhanced Chemical Vapor Deposition of Silicon Nitride and Oxynitride Films Using Disilane as Silicon Source. Giridhar Nallapati Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Nallapati, Giridhar, "Plasma Enhanced Chemical Vapor Deposition of Silicon Nitride and Oxynitride Films Using Disilane as Silicon Source." (1999). LSU Historical Dissertations and Theses. 6899. https://digitalcommons.lsu.edu/gradschool_disstheses/6899 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. 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PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION OF SILICON NITRIDE AND OXYNITRIDE FILMS USING DISILANE AS SILICON SOURCE A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Electrical and Computer Engineering by Giridhar Nallapati B.S., Mangalore University, India, 1990 M.S., Louisiana State University, 1992 May 1999 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 9925540 UMI Microform 9925540 Copyright 1999, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Dedicated to my parents ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENTS I would like, first, to express my deepest appreciation for the technical guidance and support given by my research advisor, Professor Pratul K. Ajmera. His thorough understanding of the m any issues fundamental to semiconductor device physics and device operation, his attention to detail and basics that most often govern the behavior of even the most complex of problems will always be remembered. Needless to say, his belief in me made this work posible. I would like to thank Drs. Kerry Dooley, Richard Kurtz, Gil Lee, Alexander Skavantzos and Ashok Srivastava for being a part of my dissertation committee. Special thanks to Dr. Rich Kurtz for being my minor professor. I want to dedicate this work to my parents who, for inexplicable and sometimes unjustified reasons, always believed in me. These are two people I could always take for granted as though it is expected of me. The two most special people I had a chance to associate myself with while at LSU are Dr. Juho Song, my fellow Ph. D. candidate and mentor (if that’s possible), and Golden Hwaung, a person without whose help I would still be toiling trying to make my experimental setup work. Golden’s practical knowledge of a broad range of things is a constant source of awe and inspiration. He is troubleshooter personified. I am thankful to Juho for giving me a direction both during and after my academic life. There are countless other people whose names and faces pass through my mind as I ruminate about this period at LSU. People that I am lucky enough to know and get to know. Listing all those names would definitely make me miss this dissertation deadline. So, I would have to include all of them in saying that it was really a pleasure til Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. knowing them and that aspect, as much as anything else, made this whole thing worthwhile. Last, but not the least, I gratefully acknowledge the equipment grant, from the Louisiana Education Quality Support Fund granted by the Louisiana Board of Regents, that was used in acquiring the plasma CVD equipment used in this work. iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS D ED ICA TIO N ..................................................................................................................ii ACKNOWLEDGEMENTS.......................................................................................... iii LIST O F T A B LES.........................................................................................................vii LIST OF FIGURES..................................................................................................... viii ABSTRACT................................................................................................................... xii CHAPTER 1. INTRODUCTION.................................................................................. 1 1.1 History of Silicon Nitride and Oxynitride Layer Usage in Semiconductor Industry ................................................................................. 1 1.2 Impetus for Alternate Dielectrics and Dielectric Formation Processes 3 1.3 Plasma Enhanced Chemical Vapor Deposition(PECVD) and Plasma Chem istry ....................................................................................................... 8 1.3.1 The SiH 4 -NH3 System......................................................................10 1.3.2 The SiH 4-N2 System.......................................................................... 14 1.4 Film Properties : A Brief Review ..............................................................16 1.4.1 Silicon Nitride Films .........................................................................16 1.4.2 Silicon Oxynitride Films .................................................................. 20 1.5 Research Objectives ................................................................................... 20 1.6 O rganization ............................................................................................... 21 1.7 Deposition System and Characterization Equipment ...............................22 1.7.1 Plasma Deposition System ...............................................................22 1.7.2 Characterization Equipment ............................................................ 24 CHAPTER 2. SILICON NITRIDE FILM DEPOSITION .................................... 25 2.1 Introduction ................................................................................................ 25 2.2 Experiment ................................................................................................. 27 2.3 Results and Discussion .............................................................................. 29 2.4 Summary and Conclusions .........................................................................41 CHAPTER 3. ELECTRICAL PROPERTIES OF SILICON NITRIDE FILMS ...................................................................................................44 3.1 Introduction ................................................................................................ 44 3.2 Experiment ................................................................................................. 44 3.3 Rekilts and Discussion ..............................................................................45 3.4 Summary and Conclusions .........................................................................55 CHAPTER 4. EFFECTS OF PRE- AND POST-DEPOSITION PROCESSING ON ELECTRICAL PROPERTIES......................58 4.1 Introduction ................................................................................................ 58 4.2 Experiment ................................................................................................