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A Study of Ion Implanted Silicon Using Rutherford Backscattering Spectroscopy with Ion Channeling Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 12-1987 A Study of Ion Implanted Silicon Using Rutherford Backscattering Spectroscopy with Ion Channeling Thomas J. Pollock Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Atomic, Molecular and Optical Physics Commons Recommended Citation Pollock, Thomas J., "A Study of Ion Implanted Silicon Using Rutherford Backscattering Spectroscopy with Ion Channeling" (1987). Master's Theses. 1245. https://scholarworks.wmich.edu/masters_theses/1245 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. A STUDY OF ION IMPLANTED SILICON USING RUTHERFORD BACKSCATTERING SPECTROSCOPY WITH ION CHANNELING by Thomas J. Pollock A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements for the Degree of Master of Arts Department of Physics Western Michigan University Kalamazoo, Michigan December 1987 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. A STUDY OF ION IMPLANTED SILICON USING RUTHERFORD BACKSCATTERING SPECTROSCOPY WITH ION CHANNELING Thomas J. Pollock, M.A. Western Michigan University, 1985 Rutherford Backscattering Spectroscopy with channeling is the only nondestructive method for analyzing crystals which have been ion implanted. An RBS with channeling procedure has been established at the Accelerator Laboratory of Western Michigan University. It utilizes a tandem Van de Graaff accelerator for an incident helium beam, a goniometer for crystal alignment, and a computer for experi­ mental control and data aquisition. State of the art measurements can be made with accuracies comparable to other labs. Specifically, ion implanted silicon was studied wherein crystal damage due to implanting was found to vary directly with implanting energy and fluence and was also reduced by subsequent annealing. Further research efforts will find this experimental setup very productive. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENTS Very special thanks go to my advisor, Dr. Stephen Ferguson, for his gracious patience and insight. I would like to thank Leo Parpart and Chuck Mielke for their needed assistence. I also would like to thank WMU’s Physics Department for a rewarding and learned degree. We learn to understand. Then we have a breakthrough and understand we need to learn more. Thomas J. Pollock ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1.The sign or “target” for pages apparently lacking from the document photographed is “Missing Page(s)”. If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. 2. 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These prints are available upon request from the Dissertations Customer Services Department. 5. Some pages in any document may have indistinct print. In all cases the best available copy has been filmed. University Miaorilms International 300 N. Zeeb Road Ann Arbor, Ml 48106 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Order Number 1332405 A study of ion implanted silicon using Rutherford Backscattering Spectroscopy with ion channeling Pollock, Thomas J., M.A. Western Michigan University, 1987 UMI 300 N. Zeeb Rd. Ann Arbor, MI 48106 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V . 1. Glossy photographs or pages_____ 2. Colored illustrations, paper or print_______ 3. Photographs with dark background_____ 4. Illustrations are poor copy_______ 5. Pages with black marks, not original copy 6. Print shows through asthere is text on both sides of pag________ e 7. Indistinct, broken or small print on several pagest * / 8. Print exceeds margin requirements______ 9. Tightly bound copy with print lost in spine_______ 10. Computer printout pages with indistinct print_______ 11. Page(s)____________lacking when material received, and not available from school or author. 12. Page(s)____________seem to be missing in numbering only as text follows. 13. Two pages numbered . Text follows. 14. Curling and wrinkled pages______ 15. Dissertation contains pages with print at a slant, filmed as received__________ 16. Other____________________________________________________________________________ UMI Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ACKNOWLEDGEMENTS.................................... ii LIST OF F I G U R E S ...................................... vi INTRODUCTION .................. 1 REVIEW OF THEORY .......................................... 3 Rutherford Scattering ...................................... 3 Ion C h a n n e l i n g .............................................. 5 Interpretation of Spectra... ............................... 6 EXPERIMENTAL SETUP ............................................ 14 G o n i o m e t e r ...................... 16 C o m p u t e r ....................................................20 EXPERIMENTAL PROCEDURE ...................................... 22 Sample Preparation and Mounting ............................ 22 Locating a C h a n n e l .......................... 23 Annealing Procedure ........................................ 27 RESULTS ........................................................31 CONCLUSION AND RECOMMENDATIONS ...................... ..... 40 APPENDICES............................ 43 A. CHAN Program . ..................................... 43 B. Use and Production of CP-4A Etchant...................... 49 C. Energy Calibration of Spectra............ 51 BIBLIOGRAPHY .................................................. 54 iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES 1. Critical Angle .......................... 7 2. Spectra for Single Atom Crystal.............. 9 3. Spectra of Implanted Crystal . .................... 10 4. True Interstitial I m p u r i t y .................................. 13 5. Accelerator Layout ........................................ 15 6. Scattering C h a m b e r .......................................... 17 7. Goniometer ............ 18 8. Mechanical Drawing of Goniometer .......................... 19 9. Horizontal 360 Degree S c a n ..................................24 10. Polar P l o t .................... 25 11. Gold on Silicon Spectra...................................... 29 12. Unimplanted Silicon Spectra........................ 30 13. Implanted Silicon Spectra ................................. .33 14. Implanted Silicon Spectra ................................... 34 15. Implanted Silicon Spectra ................................... 36 16. Implanted Silicon Spectra ................................. 37 17. Spectra of Annealed Silicon.................................. 39 18. Detector at Glancing A n g l e .......................... 42 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. INTRODUCTION Nondestructive analyses of the near surface of a material can be done with Rutherford Backscattering Spectroscopy (RBS). Furthermore, using
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