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Tin Sensitization for Electroless Plating Xingfei Wei University of Arkansas, Fayetteville

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Tin Sensitization for Electroless Plating Xingfei Wei University of Arkansas, Fayetteville University of Arkansas, Fayetteville ScholarWorks@UARK Theses and Dissertations 12-2013 Tin Sensitization For Electroless Plating Xingfei Wei University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/etd Part of the Organic Chemistry Commons, and the Process Control and Systems Commons Recommended Citation Wei, Xingfei, "Tin Sensitization For Electroless Plating" (2013). Theses and Dissertations. 976. http://scholarworks.uark.edu/etd/976 This Thesis is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. Tin Sensitization For Electroless Plating Tin Sensitization For Electroless Plating A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemical Engineering By Xingfei Wei Zhejiang University Bachelor of Energy & Environment Systems Engineering, 2010 December 2013 University of Arkansas This thesis is approved for recommendation to the Graduate Council. Dr. Donald Keith Roper Thesis Director Dr. Rick Ulrich Dr. Jingyi Chen Committee Member Committee Member ABSTRACT The tin sensitization process has been used in electroless plating since 1940s Brenner and Riddell developed the electroless plating for surface metallization method. It was found to be an interesting topic to study tin sensitization for chemically controlling metal deposition on different substrates, because the tin sensitization process had critical effects on the electroless plated metal thin films. Nowadays electroless plating metal deposition is still an important method for depositing metals. It has a few advantages over the vapor deposition and electrodeposition method, such as work in an ambient condition, on nonconductive substrates, and without extra power input. Applying electroless plating our lab has successfully fabricated ordered array of gold nanostructures, for example Dr. Blake fabricated gold nano rings by top-down electron- beam lithography, and Dr. Ahn fabricated hexagonal gold nano particles by bottom-up silica sphere self-assembly. Dr. Jang studied the silver catalytic particle formation and gold thin film dynamically formation in detail. However, the tin sensitization process has not be studied yet. Therefore, in this master’s thesis the tin sensitization for electroless plating was researched. In Chapter I an introduction was given for the tin sensitization process and the electroless plating method. In Chapter II the tin sensitization process for elctroless plating was reviewed. In Chapter III a rapid, straightforward, spectrophotometric method, based on the redox reaction of tin(II) with a mixture of N-bromosuccinimide (NBS) and 3,3’,5,5’-tetramethylbenzidine dihydrochloride (TMB-d) was developed for determining low concentrations of tin(II). In Chapter IV the spectrophotometric method developed in Chapter II was developed for quantitative measurement of stannous (tin(II)) concentrations on ceramic substrates. Effects of reagent concentration, exposure time, substrate physicochemistry, and post-exposure conditions on surface tin(II) content were evaluated. Aqueous immersion post-reaction doubled tin(II) surface concentration compared to drying in nitrogen before a two-minute air exposure. In Chapter V the 2D hexagonal arrays of gold nano rings were fabricated by coupling EBL and electroless plating. The future work of applying the results in this thesis was proposed in Chapter VI. Two directions were suggested, uniform metal deposition that could be comparable to vacuum deposition methods and fabricating ordered array of metal nanostructures. ACKNOWLEDGEMENTS Special thanks are due to the Department of Chemical Engineering of the University of Arkansas for all the support with the study and research. Thank Dr. Roper for advising me in experiment and writing scientific articles. Without Dr. Roper’s advising and help this work would not have been accomplished. Thank Prof. Ken Vickers for providing valuable advice. Thank Dr. Gyoung Gug Jang for his initial guide in the research. Thank Dr. Phillip Blake for his supervision on the research. Thank Dr. Milana Oleksandrivna Lisunova for her supervision in experiment and help with the thesis. Also thank all the group members for their help and discussions in the experiment. Jeremy, Greg, Drew, Vinith and Keith, thank you all for your help in the experiment setting up and results discussion. It was a great pleasure to work with you all. Finally, I thank my parents and friends for their supporting. Also, special thanks go out to the faculty and staff at the University of Arkansas and in the Department of Chemical Engineering for their commitment to the University and to the students. TABLE OF CONTENTS I. INTRODUCTION ................................................................................................................. 1 A. REFERENCES ................................................................................................................... 3 II. TIN SENSITIZATION REVIEW ........................................................................................ 5 B. INTRODUCTION.............................................................................................................. 5 C. CHARACTERISTICS OF TIN SENSITIZED SURFACES ......................................... 6 Chemical composition of the tin .............................................................................................. 6 Contact angle measurement ..................................................................................................... 7 Catalytic sites ........................................................................................................................... 9 Metal deposition island morphology ..................................................................................... 11 D. CONDITIONS TO PROCEED TIN SENSITIZATION .............................................. 12 Aging solution ....................................................................................................................... 12 Substrates ............................................................................................................................... 13 E. TRIFLUOROACETIC ACID (TFA) IN TIN SENSITIZATION SOLUTION ......... 15 F. PHOTO SELECTIVE METAL DEPOSITION (PSMD) ............................................ 16 Idea development ................................................................................................................... 16 Mechanism discuss ................................................................................................................ 17 G. SINGLE-STEP TINSENSITIZATION ......................................................................... 19 Method development and comparison with two-step system ................................................ 19 Accelerator............................................................................................................................. 21 Electrochemical method study............................................................................................... 21 H. TIN SENSITIZAITON MECHANISM DEVELOPMENT ......................................... 22 Conventional two-step system ............................................................................................... 22 Single-step catalyzing system ................................................................................................ 26 I. APPLICATION OF TIN SENSITIZATION ................................................................ 27 J. CONCLUSION ................................................................................................................ 28 K. REFERENCES ................................................................................................................. 30 III. SPECTROPHOTOMETRIC METHOD FOR ANALYZING TIN(II) BY REDOX REACTION USING 3,3’,5,5’-TETRAMETHYLBENZIDINE DIHYDROCHLORIDE AND N-BROMOSUCCINIMIDE ............................................................................................. 34 A. INTRODUCTION............................................................................................................ 34 B. EXPERIMENTAL METHOD ........................................................................................ 39 Apparatus ............................................................................................................................... 39 Reagents................................................................................................................................. 40 Procedure ............................................................................................................................... 40 C. RESULTS AND DISCUSSION ...................................................................................... 42 Mechanism............................................................................................................................. 42 Optimum detection condition ................................................................................................ 45 Evaluation of Method ............................................................................................................ 50 D. CONCLUSIONS .............................................................................................................. 52 E. REFERENCES
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