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Scanning Tunneling Optical Resonance Microscopy Applied to Indium Arsenide Quantum Dot Structures

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Scanning Tunneling Optical Resonance Microscopy Applied to Indium Arsenide Quantum Dot Structures Rochester Institute of Technology RIT Scholar Works Theses 6-1-2008 Scanning tunneling optical resonance microscopy applied to indium arsenide quantum dot structures Daniel P. Byrnes Follow this and additional works at: https://scholarworks.rit.edu/theses Recommended Citation Byrnes, Daniel P., "Scanning tunneling optical resonance microscopy applied to indium arsenide quantum dot structures" (2008). Thesis. Rochester Institute of Technology. Accessed from This Thesis is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. SCANNING TUNNELING OPTICAL RESONANCE MICROSCOPY APPLIED TO INDIUM ARSENIDE QUANTUM DOT STRUCTURES By Daniel P. Byrnes B.A. State University of New York at Geneseo (2004) A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in the Chester F. Carlson Center for Imaging Science of the College of Science June 2008 Signature of the Author_________________________________________________ Accepted by__________________________________________________________ Coordinator, M.S. Degree Program Date CHESTER F. CARLSON CENTER FOR IMAGING SCIENCE COLLEGE OF SCIENCE ROCHESTER INSTITUTE OF TECHNOLOGY ROCHESTER, NEW YORK CERTIFICATE OF APPROVAL ________________________________________________________________________ M.S. DEGREE THESIS ________________________________________________________________________ The M.S. Degree Thesis of Daniel P. Byrnes has been examined and approved by the thesis committee as satisfactory for the thesis requirement for the Master of Science degree ____________________________________ Dr. Ryne Raffaelle ____________________________________ Professor Richard Hailstone ____________________________________ Dr. Michael Kotlarchyk ____________________________________ Date ii THESIS RELEASE PERMISSION ROCHESTER INSTITUTE OF TECHNOLOGY COLLEGE OF SCIENCE CHESTER F. CARLSON CENTER FOR IMAGING SCIENCE Title of Thesis: SCANNING TUNNELING OPTICAL RESONANCE MICROSCOPY APPLIED TO INDIUM ARSENIDE QUANTUM DOT STRUCTURES I, Daniel P. Byrnes, hereby grant permission to the Wallace Memorial Library of R.I.T. to reproduce my thesis in whole or in part. Any reproduction will not be for commercial use or profit. Signature:_________________________________ Date:_____________________________________ iii SCANNING TUNNELING OPTICAL RESONANCE MICROSCOPY APPLIED TO INDIUM ARSENIDE QUANTUM DOT STRUCTURES By Daniel P. Byrnes B.A. State University of New York at Geneseo (2004) Submitted to the Chester F. Carlson Center for Imaging Science College of Science in partial fulfillment of the requirements for the Master of Science Degree at the Rochester Institute of Technology ABSTRACT The technique of Scanning Tunneling Optical Resonance Microscopy (STORM) has been investigated for use on nanostructures. It has been demonstrated as a viable technique to characterize both bulk and nanostructured materials by optically pumping the tip-sample junction with variable energy photons thereby changing the electronic signature in the scanning tunneling microscope allowing for the determination of the local absorption spectrum. STORM offers an alternative technique to characterize very small structures that lie beyond the limits of more conventional approaches. iv ACKNOWLEDGEMENTS I would like to thank NASA Glenn Research Center in Cleveland, Ohio for allowing me use of all of the equipment available. I am especially grateful for the support of Dr. Padetha Tin and Dr. Sheila Bailey during my residence at NASA Glenn. Dr. Seth Hubbard was a source of inspiration, knowledge and encouragement at NASA as well as RIT. He grew all of the samples presented in this work and played a pivotal role during the course of my research. I would like to thank my colleagues at Veeco Turbodisc for allowing me to use their time to finish the work presented in this manuscript. Thank you to my employer Dr. Dong Lee for his support and encouragement to complete the research. I would also like to thank Dr. Ryne Raffaelle for offering encouragement. Finally, I would like to thank all of my friends and family. Thank you. v TABLE OF CONTENTS ABSTRACT...................................................................................................................... iv ACKNOWLEDGEMENTS ............................................................................................. v TABLE OF CONTENTS ................................................................................................ vi TABLE OF FIGURES.................................................................................................... vii LIST OF TABLES ........................................................................................................... ix I INTRODUCTION......................................................................................................... 1 1.1 MOTIVATION........................................................................................................ 1 1.2 SCANNING TUNNELING MICROSCOPY.......................................................... 7 1.3 ATOMIC FORCE MICROSCOPY....................................................................... 10 1.4 TI:SAPPHIRE RING LASER ............................................................................... 13 1.5 METAL ORGANIC CHEMICAL VAPOR DEPOSITION (MOCVD)............... 14 II EXPERIMENT .......................................................................................................... 15 2.1 STORM SETUP..................................................................................................... 15 2.2 STM TIP PREPARATION.................................................................................... 17 III RESULTS.................................................................................................................. 20 3.1 GALLIUM ARSENIDE STUDY......................................................................... 20 3.2 QUANTUM DOT MEASURMENT..................................................................... 25 IV CONCLUSIONS & RECOMMENDATIONS ...................................................... 48 4.1 FUTURE RESEARCH AND DEVELOPMENT.................................................. 48 4.2 CONCLUSION...................................................................................................... 52 V APPENDIX A ............................................................................................................. 53 VI REFERENCES ......................................................................................................... 57 vi TABLE OF FIGURES Figure 1. Schematic of STM operation showing atomic interaction between the tip and sample. ........................................................................................................................ 9 Figure 2. (a) Schematic of first AFM setup with STM as delflection detector. (b) Modern AFM using optical lever to sense the vertical position of the cantilever. ... 11 Figure 3. Schematic representation of STORM experimental setup. .............................. 16 Figure 4. STM tip etching setup. ..................................................................................... 19 Figure 5. Spectra of GaAs samples (a) STORM (b) PL (c) STORM and PL overlay for comparison................................................................................................................ 21 Figure 6. STORM spectra of GaAs samples with different doping levels. ..................... 23 Figure 7. Low temperature PL of quanutm dot samples.................................................. 24 Figure 8. Quantum dot low temperature PL spectra........................................................ 26 Figure 9. AFM of Sample A (a) Height image (b) 3-D image. ....................................... 29 Figure 10. AFM of Sample B (a) Height image (b) 3-D image....................................... 30 Figure 11. AFM of Sample C (a) Height image (b) 3-D image....................................... 31 Figure 12. AFM of Sample D (a) Height image (b) 3-D image. ..................................... 32 Figure 13. AFM of Sample E (a) Height image (b) 3-D image....................................... 33 Figure 14. PL Spectra of quantum dot samples. .............................................................. 35 Figure 15. Overlay of PL spectra for comparison............................................................ 37 Figure 16. Sample B STORM and PL signal overlay...................................................... 38 Figure 17. Sample C STORM and PL signal overlay...................................................... 39 Figure 18. Sample D STORM and PL signal overlay. .................................................... 40 vii Figure 19. Sample E STORM and PL signal overlay...................................................... 41 Figure 20. STORM spectra ovelaid to show lamp/monochromator system efficiency effects........................................................................................................................ 44 Figure 21. STORM spectra of all samples....................................................................... 45 Figure 22. STORM spectrum of sample A. ..................................................................... 47 Figure 23. Illustration showing increased output of second harmonic using a periodic poling technique.......................................................................................................
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