simultaneous reflection and transmission measurements of scandium oxide thin films in the extreme...
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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 AstronomyBrigham Young University
Provo, Utah
My most sincere thanks…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
We measure thin films in the extreme ultraviolet
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)
β(ω) can be found from transmission data, and reflection data can be used to find δ(ω).
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)
β(ω) can be found from transmission data, and reflection data can be used to find δ(ω).
photodiode
coated photodiode
transmission measurement
reflection measurement
Energy can only go three places:
Transmitted, Reflected, Absorbed
Energy can only go three places:
Transmitted, Reflected, Absorbed
Sometimes…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
Collect transmission and reflection data simultaneously
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
A New StageA New Stage
Essentially all angles availableEssentially all angles available
The migrating peaks in the reflection data are interference
fringes.
Bragg’s Law m* =d*sin
and are known.
The migrating peaks in the reflection data are interference
fringes.
Bragg’s Law m* =d*sin
and are known.
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27
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Reflectance of Scandium Oxide Thin Film
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
2.70 2.95 3.20 3.45 3.70 3.95 4.20 4.45 4.70
Wavelength (nm)
Ref
lect
ance
(%
)
8.2 degrees10 degrees11.5 degrees14.5 degrees
29
Reflectance of Scandium Oxide Thin Film
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
2.70 2.95 3.20 3.45 3.70 3.95 4.20 4.45 4.70
Wavelength (nm)
Ref
lect
ance
(%
)
8.2 degrees10 degrees11.5 degrees14.5 degrees
30
Reflectance of Scandium Oxide Thin Film
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
2.70 2.95 3.20 3.45 3.70 3.95 4.20 4.45 4.70
Wavelength (nm)
Ref
lect
ance
(%
)
8.2 degrees10 degrees11.5 degrees14.5 degrees
31
Reflectance of Scandium Oxide Thin Film
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
2.70 2.95 3.20 3.45 3.70 3.95 4.20 4.45 4.70
Wavelength (nm)
Ref
lect
ance
(%
)
8.2 degrees10 degrees11.5 degrees14.5 degrees
32
Reflectance of Scandium Oxide Thin Film
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
2.70 2.95 3.20 3.45 3.70 3.95 4.20 4.45 4.70
Wavelength (nm)
Ref
lect
ance
(%
)
8.2 degrees10 degrees11.5 degrees14.5 degrees
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.
Calculations of Scandium Oxide predict the L edge at 397.4 eV
Calculations of Scandium Oxide predict the L edge at 397.4 eV
Measurements show the edge at 402.6 eV
In conclusion…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
