1. Simultaneous Reflection and Transmission Measurements of Scandium Oxide Thin Films in the Extreme Ultraviolet Guillermo Acosta Dr. David Allred Dr. R. Steven Turley Niki Farnsworth Jed Johnson Department of Physics and Astronomy Brigham Young University Provo, Utah

2. My most sincere thanks…  Mr. W. Lifferth, Mr. M. Erickson, Mr. W. S. Daniel, Mr. J. Ellsworth  Nan Ah You and the Physics Department Front Office Staff  WAESO and MGE@MSA  Rocky Mountain NASA Space Grant Consortium  Mr. W. Lifferth, Mr. M. Erickson, Mr. W. S. Daniel, Mr. J. Ellsworth  Nan Ah You and the Physics Department Front Office Staff  WAESO and MGE@MSA  Rocky Mountain NASA Space Grant Consortium

3. We measure thin films in the extreme ultraviolet  Measurements are made at Advanced Light Source, Lawrence Berkeley National Laboratory  Preferred technique for collecting transmission data is a thin film deposited on a photodiode (Seely, Korde, SPIE Meeting 1999; Seely, Uspenskii, J. Opt. Soc. Am 2004)   (  ) can be found from transmission data, and reflection data can be used to find  (  ).  Measurements are made at Advanced Light Source, Lawrence Berkeley National Laboratory  Preferred technique for collecting transmission data is a thin film deposited on a photodiode (Seely, Korde, SPIE Meeting 1999; Seely, Uspenskii, J. Opt. Soc. Am 2004)   (  ) can be found from transmission data, and reflection data can be used to find  (  ).

4. photodiode

5. coated photodiode

6. transmission measurement

7. reflection measurement

8. Energy can only go three places: Transmitted, Reflected, Absorbed

9. Sometimes…  Samples are not uniform  Photodiode does not have absolute uniform response  Beam intensity changes  Short on time  Samples are not uniform  Photodiode does not have absolute uniform response  Beam intensity changes  Short on time

10. Collect transmission and reflection data simultaneously  Measurements would be from exactly the same spot of the sample.  Twice as much data, strongly correlated allows for more robust model  Optimize beam time  Measurements would be from exactly the same spot of the sample.  Twice as much data, strongly correlated allows for more robust model  Optimize beam time

11. A New Stage

12. Essentially all angles available

25. The migrating peaks in the reflection data are interference fringes. Bragg’s Law m* =d*sin  and  are known.

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33. 33  The coincidence of maxima and minima from data collected at two different angles may allow for the index of refraction to cancel out of equation.  This would only leave m and d as unknown.  The coincidence of maxima and minima from data collected at two different angles may allow for the index of refraction to cancel out of equation.  This would only leave m and d as unknown.

34. Calculations of Scandium Oxide predict the L edge at 397.4 eV Measurements show the edge at 402.6 eV

35. In conclusion…  Reflection and transmission data are collected from exactly the same portion of the sample  One set of physical parameters will be appropriate for analyzing both sets of data  Measurements of scandium oxide thin films are different from accepted predictions  Reflection and transmission data are collected from exactly the same portion of the sample  One set of physical parameters will be appropriate for analyzing both sets of data  Measurements of scandium oxide thin films are different from accepted predictions

36. Thank you. acosta_g@hotmail.com