astronomical institute, academy of sciences of the czech republic, ondřejov, czech republic czech...
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Astronomical Institute, Academy of Sciences of the Czech Republic, Ondřejov, Czech Republic
Czech Technical University, Prague, Czech Republic
Centre for Advanced X-ray Technologies, Reflex sro, Czech Republic
Institute of Chemical Technology, Prague, Czech Republic
ON Semiconductor, Rožnov pod Radhoštěm, Czech Republic
Novel X-ray Optics
with Si Wafers and Formed
Glass
Novel X-ray Optics
with Si Wafers and Formed
GlassIBWS Vlasim 2006
R. Hudec, L. Pína, A. Inneman, V. Semencová, M. Skulinová, L. Švéda, V. Brožek, J. Šik, M. Míka, R. Kačerovský, J.
Prokop
R. Hudec, L. Pína, A. Inneman, V. Semencová, M. Skulinová, L. Švéda, V. Brožek, J. Šik, M. Míka, R. Kačerovský, J.
Prokop
Long Term ISS Utilisation
ESA XEUS
XEUS will have a very large collecting area and fine angular resolution of 2..5" so very light-weight novel X-ray optics is to be developed
Czech participation
• ESA PECS project accepted for funding from Dec 2006, PI L. Pina Reflex, CI ASU, VSCHT, FJFI CVUT. Duration 4 years.
• Preliminary results described in this talk were obtaained WITHOUT any funding thanks to the enthuniasmus of participants.
1. the Si wafers parameters are optimized already at the production stage
2. the Si wafers are shaped to precise optical surfaces/shapes
3. the internal stress is minimized. Important. The standard Si wafers are not stress-free.
4. the shaped/bent Si wafers are stacked to form the Multi Foil Optics (MFO)
1. the Si wafers parameters are optimized already at the production stage
2. the Si wafers are shaped to precise optical surfaces/shapes
3. the internal stress is minimized. Important. The standard Si wafers are not stress-free.
4. the shaped/bent Si wafers are stacked to form the Multi Foil Optics (MFO)
Our approach to X-ray optics based on Si wafers
Our approach to X-ray optics based on Si wafers
the production of Si wafers is a complex process. The recent Si wafers are optimized for semiconductor industry but not for X-ray optics applications
we use Si wafers already at production optimized for X-ray optics application
precise measurements and optimization already at production stage are important for X-ray optics based on Si wafers
the production of Si wafers is a complex process. The recent Si wafers are optimized for semiconductor industry but not for X-ray optics applications
we use Si wafers already at production optimized for X-ray optics application
precise measurements and optimization already at production stage are important for X-ray optics based on Si wafers
Measuring the quality of flat
Si wafers
Measuring the quality of flat
Si wafers
Comparison of properties of Si wafers produced by different
manufacturers
Comparison of properties of Si wafers produced by different
manufacturers
CZ2 – ON Semiconductor Czech Republic
MEMC – MEMC Electronic Materials
SHE – Shin Etsu SEH
WW – Wafers Works
standard Si wafersstandard Si wafers
Thickness homogeneity of standard Si wafer
Thickness homogeneity of standard Si wafer
Flatness and thickness uniformity of a standard Si wafer (diameter 150 mm). Expected to
further improve due to technological innovations planned.
Flatness and thickness uniformity of a standard Si wafer (diameter 150 mm). Expected to
further improve due to technological innovations planned.
min. thickness 686.07 m
max.thickness 687.75 m
ave. thickness 687.18 m
cen. thickness 686.92 m
TTV Total Thickness Variation
1.68 m
TIR Total Indicated Reading
1.81 m
produced by ON Semiconductor Czech Republicproduced by ON Semiconductor Czech Republic
6“ Silicon Wafer Manufacturing Process Flow Chart
CHEMICAL CLEANING
SINGLE CRYSTAL GROWING
INGOT SHAPING EVALUATION
SLICING EDGE GRINDING
LASER MARKING*
LAPING AND CLEANING
ACID ETCH ANNEALING*
BACKSIDE TREATMENT*
BACKSEAL OXIDE, POLYSILICON*
New step: GRINDING
POLISHING
MECHANICAL CLEANING
FLATTING
* Optional INSPECTION
Ground Si wafer
TTV 0.37 m
Diamond Grinding Technology for Ideal Flatness
6“ Silicon Polished Wafer: Flatness Evolution (TTV)
TTV = 0.76 m TTV = 1.68 m
TTV < 2 m (2005)process optimization
TTV < 1 m (2006)grinding technology
TTV < 0.5 m (2007)new polisher (ordered)
measured Total Thickness Variation
flat Si wafer (dopant As), D = 150 mm, t = 0.625 mmSpecial very flat Si wafers have been developed
in the collaborating industry for use in X-ray optics
flat Si wafer (dopant As), D = 150 mm, t = 0.625 mmSpecial very flat Si wafers have been developed
in the collaborating industry for use in X-ray optics
Measuring of shape Measuring of shape Still optical profilometer – 3D chartStill optical profilometer – 3D chart
Flat Si wafer, D = 150 mm, t = 0.625 mm ON Semiconductor Czech Republic,
Taylor-Hobson profilometer, 2 perpendicular axes
Flat Si wafer, D = 150 mm, t = 0.625 mm ON Semiconductor Czech Republic,
Taylor-Hobson profilometer, 2 perpendicular axes
Flatness better than 1 m
Flat Si wafer D=150 mmt=0.625 mm)ON SEMICONDUCTOR
Measuring of microroughness
Measuring of microroughness
AFM microscope, Ra ~ 0.1 nm in 10 x 10 mAFM microscope, Ra ~ 0.1 nm in 10 x 10 m
Measuring of roughnessMeasuring of roughness
Interferometer Zygo, Ra ~ 0.2 nm in 1.4 x 1.1 mmInterferometer Zygo, Ra ~ 0.2 nm in 1.4 x 1.1 mm
dopant B, D = 150 mm, t = 0.625 mm
ON Semiconductor, Czech Republic
dopant B, D = 150 mm, t = 0.625 mm
ON Semiconductor, Czech Republic
Measuring of roughnessMeasuring of roughness
Interferometer ZygoInterferometer Zygo
effect of various dopants on roughness
effect of various dopants on roughness(boron-B and phosphorus-P)(boron-B and phosphorus-P)
SHAPING OF SI WAFERSSHAPING OF SI WAFERS
the goal is to precisely shape Si wafers to desired optical shape and to remove the internal stress
3 different technologies tested (I, II, III)
so far, Si wafers have been shaped to test cylindrical and parabolic surfaces both in 1 and in 2 dimensions
the goal is to precisely shape Si wafers to desired optical shape and to remove the internal stress
3 different technologies tested (I, II, III)
so far, Si wafers have been shaped to test cylindrical and parabolic surfaces both in 1 and in 2 dimensions
Si wafers shaping Si wafers shaping test cylindrical samples
gold-coated, D=100-150 mm, t=0.8-1.3 mm, R=1.5 mtest cylindrical samples
gold-coated, D=100-150 mm, t=0.8-1.3 mm, R=1.5 m
Bent (cylinder) Si wafer R = 1650 mm, D=150 mm, t = 1.3 mm
Bent (cylinder) Si wafer R = 1650 mm, D=150 mm, t = 1.3 mm
Measuring of roughness after shaping
Measuring of roughness after shaping
Interferometer ZygoInterferometer Zygoconcave sideconcave side convex sideconvex side
flat Si wafer (dopant P)D = 150 mmt = 0.625 mm
flat Si wafer (dopant P)D = 150 mmt = 0.625 mm
Measuring of shape Measuring of shape Still optical profilometer – 3D chartStill optical profilometer – 3D chart
bent Si wafer (dopant P)D = 150 mmt = 1.3 mmR = 1650 mm
bent Si wafer (dopant P)D = 150 mmt = 1.3 mmR = 1650 mm
Deviation bent Si wafersDeviation bent Si wafers
before processing(deviation from plane)± 2 µm
after processing(deviationfrom cylinder)± 2.5 µm
Parabolically shaped Si wafer, D = 150 mm, t = 0.625 mmprofile measurement in 2 perpendicular axes
Parabolically shaped Si wafer, D = 150 mm, t = 0.625 mmprofile measurement in 2 perpendicular axes
Measuring of shape Measuring of shape Taylor-Hobson profilometer – deviation from ideal shape
D = 150 mm, t = 0.625 mm, parabolic shapeTaylor-Hobson profilometer – deviation from ideal shape
D = 150 mm, t = 0.625 mm, parabolic shape
Except edge effects PV < 0.5 m
thermally formed Si wafer to test cylinder
(R = 150 mm, 72 x 23 x 0.325 mm)
thermally formed Si wafer to test cylinder
(R = 150 mm, 72 x 23 x 0.325 mm)
Thermally formed Si wafersThermally formed Si wafers
thermally formed Si wafers to test cylinder
(R = 150 mm, 50 x 7 x 0.625 mm)
thermally formed Si wafers to test cylinder
(R = 150 mm, 50 x 7 x 0.625 mm)
Optimizing parameters of thermal forming of Si wafers
The effect of elastic tension on deviation from ideal surface (thermal forming of Si wafers)
1. Interdisciplinary co-operation (team with 11 members from 5 Institutions) created within the Czech Republic with experienced teams including researchers at the large company producing Si wafers.
2. Si wafers successfully bent to desired geometry by 3 different techniques with PV ~ 1 m in the best case.
3. The bending before stacking is advantageous eg. to avoid increase of internal stress and to allow very long-term stability of the mirror array.
4. The production of Si wafers very complex, need to modify and optimize the parameters at the production stage.
1. Interdisciplinary co-operation (team with 11 members from 5 Institutions) created within the Czech Republic with experienced teams including researchers at the large company producing Si wafers.
2. Si wafers successfully bent to desired geometry by 3 different techniques with PV ~ 1 m in the best case.
3. The bending before stacking is advantageous eg. to avoid increase of internal stress and to allow very long-term stability of the mirror array.
4. The production of Si wafers very complex, need to modify and optimize the parameters at the production stage.
SUMMARY Si wafersSUMMARY Si wafers
X-RAY OPTICS BASED
ON GLASS THERMAL
FORMING (GTF)
X-RAY OPTICS BASED
ON GLASS THERMAL
FORMING (GTF)
alternative glass technologies represent glass forming avoiding heat
alternative glass technologies represent glass forming avoiding heat
optimization of the glass material (limited)
optimization of the mandrel material/design
optimization of the GTF process
optimization of the GTF temperature and duration
The parameters of the GTF may be improved by:The parameters of the GTF may be improved by:
microroughness of float - glass not degraded
~ 0.5 nm RMS
deviation PV < 0.02 m
Expectations (goals)Expectations (goals)
Various approaches in Glass Thermal FormingVarious approaches in Glass Thermal Forming
low-cost design needed (the goal is to produce very large number of shells at a low cost)
expensive production/material are to be avoided
the mandrel material/design is important
recent design: proprietary technology (composite)
Glass Thermal Forming – one of studied approaches Glass Thermal Forming –
one of studied approaches
parabolic profileparabolic profile
parabolic profile100 x 150 x 0.7 mm
parabolic profile100 x 150 x 0.7 mm
Glass thermal forming (GTF)
Glass thermal forming (GTF)
cylinder profile
75 x 25 x 0.7 mm cylinder profile
75 x 25 x 0.7 mm
the largest samples so far 300 x 300 mm
Measuring float glass
(flat glass substrates)
used for GTF
Measuring float glass
(flat glass substrates)
used for GTF
flat thin glass , 100 x 70 x 0.75 mmflat thin glass , 100 x 70 x 0.75 mm
Measuring of roughness before slumping
Measuring of roughness before slumping
Interferometer ZygoInterferometer Zygo
bent glass , R = 150 mm, 75 x 25 x 0.75 mmbent glass , R = 150 mm, 75 x 25 x 0.75 mm
Measuring of roughness after sluming
Measuring of roughness after sluming
Interferometer ZygoInterferometer Zygo
Measuring of the roughness after slumping
Measuring of the roughness after slumping
Ra [nm]Ra
[nm]RMS[nm]RMS[nm]
Interferometer Zygo, bent glass, 75 x 25 x 0.75 mm, optimization using > 100 samples formed at different
conditions
Interferometer Zygo, bent glass, 75 x 25 x 0.75 mm, optimization using > 100 samples formed at different
conditions
minimal
value
minimal
value
Optimizing the
parameters of GTF
based on TH profilometer measurements of numerous samples
(75 x 25 x 0.75 mm, R = 150 mm) - optimization
based on TH profilometer measurements of numerous samples
(75 x 25 x 0.75 mm, R = 150 mm) - optimization
Waviness of the surface as function of time and temperature of GTF
Waviness of the surface as function of time and temperature of GTF
Measuring of shape Measuring of shape Still optical profilometer – 3D chartStill optical profilometer – 3D chart
thermally formed glass, parabolic profile R = 150 mm, 100 x 150 x 0.75 mm, PV from
ideal shape ~ 0.7 m in the best case recently
thermally formed glass, parabolic profile R = 150 mm, 100 x 150 x 0.75 mm, PV from
ideal shape ~ 0.7 m in the best case recently
surface microroughness not degraded down to measuring accuracy ~ few 0.1 nm
profile deviations 0.7 µm (peak-valley) in the best case recently, expectations < 0.02 µm
sensitive to T and other parameters of the TGF process = need for optimization
sensitive to mandrel design / material / process => need for optimization
surface microroughness not degraded down to measuring accuracy ~ few 0.1 nm
profile deviations 0.7 µm (peak-valley) in the best case recently, expectations < 0.02 µm
sensitive to T and other parameters of the TGF process = need for optimization
sensitive to mandrel design / material / process => need for optimization
SUMMARY GTFSUMMARY GTF
SUMMARYSUMMARY
Samples of test X-ray mirrors have been produced using novel technologies.
Shaped thin glass mirrors and Si mirrors have been successfully produced.
Both approaches show promising results justifying further efforts in these directions.
Samples of test X-ray mirrors have been produced using novel technologies.
Shaped thin glass mirrors and Si mirrors have been successfully produced.
Both approaches show promising results justifying further efforts in these directions.
Contact: [email protected]: [email protected]
We acknowledge collaboration with ON Semiconductor CR, Rožnov pod Radhoštěm, Optical Development Workshop of the AS CR Turnov, and TTS sro
Prague
We acknowledge collaboration with ON Semiconductor CR, Rožnov pod Radhoštěm, Optical Development Workshop of the AS CR Turnov, and TTS sro
Prague
The End
The End