0/25 National Institute for Materials Science,Tsukuba, Japan 2D XRD Imaging by Projection-Type X-Ray Microscope 1. Introduction - What s projection-type X-ray microscope? 2. Examples for inhomogeneous/patterned specimens 3. Application to stress imaging 4. Application to combinatorial imaging 5. Summary and future outlook Kenji SAKURAI
2θ Why 2D Imaging for X-Ray Diffraction? Because inhomogeneous system is usual for many sciences identification of materials - mixed crystal - polymorphism poly-crystalline materials - ceramics - metals - organic crystals 1/25 Microstructure - phase transition -diffusion Inhomogeneous mixture Grain boundaries Textures Macrostructure - grain growth - preferred orientation - dendrite I Average information? physical property - residual stress - heat transfer
How to Obtain 2D Real Space Images? - Scanning vs. Projection (Reflection) Types - 2/25 Scanning type Projection type XY scan Synchrotron µ beam Sample T Wroblewski XRD (1995) K.Sakurai XRF movie (2003) X-Ray CCD camera with a collimator PC Fluorescent X-rays Diffracted X-rays Synchrotron wide beam detector High-resolution(~100nm) Sample Extremely quick(~100msec)
How Projection-type Microscope Works? Monochromator scan like EXAFS experiments 3/25 XRD imaging 2d n sinθ Bn = λ n Intensity E 0 E 1 E 2 E 3 X-Ray Energy E n =12.3981/λ n Normal XRD CCD Collimator SR Energy scan d 2 d 1 d 3 Monochromator Inhomogeneous sample
How Projection-type Microscope Works? 4/25 The experiment is just simple exposures without XY scan X-ray image Resolution: Δ= r/t d CCD BL-16A1 Photon Factory Collimator Primary X-rays r t d Sample
Cr K absorption edge 100 80 1 1 0 Examples of 2D XRD Imaging Patterned metallic Cr thin films Energy [kev] 6 7 8 9 10 11 12 13 1415 6100 ev (XRF) 1 sec x 30 5/23 Intensity 60 40 20 0 2θ 64 deg Camera- Sample 13 mm 5765 ev (XRD) 1 sec x 5 2 0 0 2 1 1 2 2 0 2.0 1.5 1.0 d [A] 8mm 8mm 3 1 1 2 2 2
1.21.31.41.51.61.70500010000150002000025000(220)(109)(1010)(300)(214)(018)(122)(116)(024)a-Al2O3Intensity[cps]1.21.31.41.51.61.70100020003000(420)(131)(401)(232)(331)(114)(140)(123)(232)(231)(222)(230)(113)(312)(311)(203)(031)(222)(311)(310)(202)HfO2Intensity[cps]1.21.31.41.51.61.705000100001500020000(833)(840)(662)(831)(660)(653)(822)(811)(800)(651)(642)(721)(640)(543)(444)(631)(622)(541)(620)(611)OCT0411Intensity[cps][ナ]HfO2 Y 2 O 3 Al 2 O 3 monoclinic HfO 2 (-401) Energy:6630eV (bragg angle: 45.31deg.) Cubic Y 2 O 3 (662) Energy:7160eV (bragg angle: 45.45deg.) alpha-al 2 O 3 (300) Energy:6345eV (bragg angle: 45.39deg.) Viewing Area 13mm 13mm Viewing Area 13mm 13mm 2d (Å) Examples of 2D XRD Imaging Different materials in the same view area 6/25
Monoclinic ZrO 2 (140) 6889eV(d=0.1266nm) Examples of 2D XRD Imaging Mapping of different phases of ZrO 2 7/25 Cubic ZrO 2 (400) 6787eV(d=0.1285nm) 13mm Intensity [Cps] Exposure Time 10 sec 10000 5000 (0 3 3) Monoclinic Cubic Energy [kev] 7 6.5 6 (1 4 0) (1 1 4) 13mm (4 0 0) (4 0 0) (4 0 1) (2 2 3) (2 3 1) (0 2 3) (2 3 0) (3 2 0) (3 1 2) (2 2 2) (1 1 3) XRD images Normal XRD 5000 0 0 1.2 1.3 1.4 1.5 d [A]
Examples of 2D XRD Imaging Mapping of different phases of TiO 2 8/23 100 2θ=76deg 2θ=84deg Viewing area 8 8mm A Intensity 50 anatase (200) rutile (210) R R Rutile Anatase 0 Incident beam:4900ev 50 100 150 θ/2θ [deg]
Examples of 2D XRD Imaging Quantitative imaging for peak overlapping cases 9/23 Intensity B 1 A 1 B 2 A 2 I 1 (x,y)= A 1 C A (x,y) +B 1 C B (x,y) I 2 (x,y)= A 2 C A (x,y) +B 2 C B (x,y) I C A (x,y) = 1 B 2 I 2 B 1 A1 B 2 A 2 B 1 E 1 E X-ray Energy 2 I C B (x,y) = 2 A 1 I 1 A 2 A1 B 2 A 2 B 1
Examples of 2D XRD Imaging 10/23 Orientation dependence of aluminum sheet (0.1mm t) (220) (311) RD RD Optical Photo Intensity [ 10 3 cps] 100 50 0 X-ray d=2.338å 3751eV (111) (200) R.D. Normal XRD 6125eV (220) d=1.431å 6130eV 40 60 80 2θ[deg.] (311) (222) 7175 ev 1.7mm Line-pattern parallel to R.D. The strongest reflection is (311). d=1.221å 7140eV d=1.1690å 7504eV Viewing Area 8mm 8mm Exposure Time 1 sec
Application to Stress Imaging 11/25 Stress analysis has been done by conventional XRD Diffraction Angle, 2θ (deg.) Stress σ x X-ray ψ 1 ψ 2 ψ 3 2θ 2θ d+ ε 1 d d+ ε 2 d d+ ε 3 d larger ψ larger ε E Young s modulus ν Possion s ratio θ Bragg angle Ψ Orientation 2θ 1 + ν 2 v ε φψ = σ x sin ψ + ( σ 1 + σ 2 ) E E σ x Stress σ x σ x 2d sin θ=λ Δd ε = = cotθ Δθ d Strain Peak shift E (2θ φψ ) π = cotθ0 2 2(1 + ν ) sin ψ 180 = K M ( ε = E 1+ ν (sin ) φψ 2 ψ ) sin 2 Ψ Changing incidence angle
Application to Stress Imaging How to extend the method to 2D imaging? 1 + ν 2 v ε φψ = σ x sin ψ + ( σ 1 + σ 2 ) E E CCD 12/25 X-rays σ x E ( ε = 1+ ν (sin E = 1+ ν = K M φψ ψ ) 1 λ 2 λ sin ψ 0 2 ) λ/λ 0 Sample 2 sin Ψ λ λ 0 plot sin 2 ψ CCD Sample is always fixed Energy scan instead of 2θ scan Changing 2θ instead of incidence angle for ψ Sin 2 ψ λ/λo plot instead of sin 2 ψ 2θ plot Monochromator X-Rays ψ 2θ
Application to Stress Imaging Imaging of welded steel 13/25 Conventional XRD pattern (Cu Kα) Welded parts Blocks (low carbon steel)
Application to Stress Imaging 2D images for Fe(200) reflections at 90 deg 14/25 6070eV 6128eV 6184eV Exposure time:5sec/image CCD steel block X-ray 90 Sample Welded part
Application to Stress Imaging 2D images for Fe(200) reflections for different ψ 15/25 X-ray CCD Sample X-ray CCD Sample X-ray CCD Sample ψ=39.0 ψ=45.0 ψ=52.5
Application to Stress Imaging 16/25 2D images of peak shift amount (X-ray wavelength) ψ=39.0 ψ=52.5 steel block ψ=45.0 Welded part
Application to Stress Imaging Finally obtained stress image from sin 2 ψ λ/λo plots Strain images for different ψ 17/25 Intensity λ/λ 0 ψ=39.0 Wavelength sin 2 ψ ψ=45.0 Intensity Wavelength Stress image Slope values for each pixel compressive Intensity tensile ψ=52.5 Wavelength
Application to Combinatorial Imaging 18/25 Efficient analysis of arrayed samples on a single substrate E 1 E 2 E 3 E 4 Single-rod fishing Net- fishing Parameters Sample-1, Sample-2,. XRD intensity Absorption XAFS XRD composition, temperature, etc. E A E B E C E D
Application to Combinatorial Imaging Y 2 O 3 Screening of high-k oxide candidates HfO 2 Cubic Y 2 O 3 (662) Energy: 7160 ev α-al 2 O 3 (300) Energy: 6345 ev 19/25 13mm Al 2 O 3 13mm Combinatorial library Graded ternary oxides sample prepared by pulsed laser deposition. A. Ahmet, Y.-Z. Yoo, K. Hasegawa, H. Koinuma, T. Chikyow Appl. Phys. A 79, 837 839 (2004). - monoclinic HfO 2 (401) Energy: 6630 ev
Application to Combinatorial Imaging 20/25 XRF/XAFS imaging of CO 2 absorbing LiFeO 2 Synthesis temperature 100 o C 200 o C 300 o C 400 o C SQ substrate CO 2 Not exposed 8mm 100 o C 30 min 200 o C 30 min CO 2 exposure 350 o C 30 min 8mm Fe-K XRF image KeK-PF BL-16A1 Incident X-ray energy : 7130 ev (above the Fe-absorption edge) Imaging time : 3 sec Pixels : 1000 x 1000 Bulk Nano particles Chemical absorption of CO 2 2 LiFeO 2 + CO 2 Li 2 CO 3 + γ-fe 2 O 3
XRF Intensity (norm) Application to Combinatorial Imaging 21/25 XRF/XAFS imaging of CO 2 absorbing LiFeO 2 Synthesis temperature 100 o C 200 o C 300 o C 400 o C 0.5eV-step x 60 points Measuring time = 9 min!! CO 2 exposure Quick change at lower temperature absorption edge shift CO 2 exposure Not exposed 100 o C x 30 min 200 o C x 30 min 350 o C x 30 min 7110 7120 7130 X-Ray Energy (ev) 200 o C 400 o C
Summary 1M pixel imaging for ~ cm 2 area 2D XRD imaging by projection-type X-ray microscope Different phases 22/25 Energy-dispersive experiments with fixed geometry Glancing angle to the sample surface 1~3 deg Diffraction angle (CCD camera position) 60~120 deg Close distance between the sample and CCD device 0.5~15 mm Collimator plate inside the CCD camera 6 mrad Imaging of inhomogeneous/patterned polycrystalline specimens difference in materials, phases, orientations Application to stress imaging Application to combinatorial imaging Combining with XRF/XAFS imaging Different orientations
Summary 23/25 Both scanning and projection-types are necessary Geometry for the sample Scanning microscope Vertical arrangement (for most cases) Projection microscope (Non-Scanning) Horizontal arrangement Typical primary beam size 0.1 2.0µm x 0.1 2.0µm 8~12mm (H) x0.4mm(v) Necessity of focusing the primary beam Absolutely necessary Desirable for vertical direction Typical spatial resolution 0.05 2µm 15 100µm Typical observation area 30 300µm x 30 300µm 8-12mm x 8-12mm Ideal polarization in terms of S/B ratio Horizontally linear Vertically linear Typical pixel numbers ca. 100 x 100 More than 1000 x 1000 Typical measuring time for one image 3 24 h 0.03 3 sec
Towards Future Projection-type microscope can be widely used Diffusion 24/25 Realtime Movie Deposition? composite materials 3D/4D Imaging Phase transition Chemical reaction Rapid Diagnostics Functionally graded materials Combinatorial screening American Chemical Society, Mitsubishi Electric Engineering Stress analysis We use a synchrotron but combination with X-ray tube is also promising..
Acknowledgement Thank you! Mari MIZUSAWA NIMS Stress imaging Hiromi EBA NIMS Masahiko Shoji NIMS Image processing Hiroshi SAWA Photon Factory, KEK Yusuke WAKABAYASHI Photon Factory, KEK Yoshinori UCHIDA Photon Factory, KEK Atsuo IIDA Photon Factory, KEK Combinatorial imaging BL-16A BL-16A BL-16A BL-4A 25/25 Active-Nano supported by MEXT, Japan government Photon Factory S-type Program References K.Sakurai, Spectrochimica Acta B54, 1497 (1999). K.Sakurai, Photon Factory Activity Report 2001 Part A, 33. K.Sakurai and H.Eba, Anal. Chem. 75, 355 (2003). M.Mizusawa and K.Sakurai, J. Synchrotron Rad. 11, 209 (2004). K.Sakurai and M.Mizusawa, AIP Conf. Proceedings (SRI-2003). (2004). K.Sakurai and M.Mizusawa, Nanotechnology, 15, S428 (2004). H.Eba and K.Sakurai, Materials Trans., 46, 665 (2005). H.Eba and K.Sakurai, Chemistry Letters, 34, 872 (2005). H.Eba and K.Sakurai, Appl. Surf. Sci., (in press). Japanese Patents 1998-229180, 2002-138834, 2002-235592, 2002-235594, 2003-318922, 2005-066097, 2005-066120, 2005-114013
Measuring Point (No.1~5) Point Analysis 2 1 3 5 4 Stress 2D image analysis region 2θ-sin 2 ψ plot σ=k M M is the slope in 2θ-sin 2 ψ plot K=-32.44kg/mm 2 /deg
Quick X-Ray Fluorescence Imaging Metallic Cr thin film on glass substrate X-ray image Incident X-ray Energy 10.0 kev X-ray Fluorescence Exposure Time 1 sec. K L M 8 mm Optical microscope image 8 mm