0. Evaluation of the SOI Pixel Detectors by Synchrotron Radiation X-ray at KEK/PF
KEK IMSS
R. Hashimoto, S. Kishimoto, R. Kumai, N. Igarashi
KEK IPNS
Y. Arai, T. Miyoshi
RIKEN
T. Hatsui, T. Kudo
IHEP
Yunpeng Lu、 Yang Zhou、 Qun Ouyang
SOKENDAI
R. Nishimura

1. Outline ・ Introduction ・ XRD experiment by the SOPHIAS detector
・ Evaluation of the counting type pixel
・ Summary

2. Introduction
Development of the SOI area detector using for X-ray structural
analysis.
・ X-ray diffraction (XRD) experiment for functional materials.
・ Small angle X-ray scattering (SAXS) experiment for functional
thin films.
etc…

3. Introduction X-ray diffraction (XRD) Å order
Structural analysis at the
atomic level
Small angle X-ray scattering (SAXS)
nm order
molecular level
Area detector using SOI +P -P
Crystal, Thin film
Precise analysis of position for hydrogen atoms
Time response of the domain structure by pulsed external electric field
X rays
Complementary use of
hard and soft X-ray
Glazing-Incidence SAXS experiment

4. Introduction Requests for detectors from experiments ・high frame rate
・high sensitivity
・high spatial resolution
Realizing by counting type pixel

5. Introduction Requests for detectors from experiments ・high frame late
・high sensitivity
・high spatial resolution
Realizing by counting type pixel
Checking the importance of the fine pixelated detector by use
of the SOPHIAS detector in X-ray structural analysis.
In this talk, our current works (following 2 topics) will be shown.
・ XRD experiment by the SOPHIAS detector
・ Evaluation of the counting type pixel

6. Outline ・ Introduction ・ XRD experiment by the SOPHIAS detector
・ Evaluation of the counting type pixel
・ Summary

7. XRD experiment by the SOPHIAS detector
SOPHIAS (RIKEN, Hatsui group)
・ Charge integrating type detector
Pixel Size
30 um×30um
Pixel Number
1.9 M
Chip size
mm ×30.58 mm
Frame Rate
60 frame/sec
Noise
150 e-rms
Depletion Depth
500
Peak Signal
7 Me-/pixel
Photon Energy limitation
< 7 keV (for FEL)
Gain
High : 7.2uV/e
Low :0.15uV /e
H:L=50:1
SOPHIAS
MPCCD
COTS CCD
Takaki. Hatsui, Vol. 27, No. 4, 2014, Synchrotron Radiation News
Allowing high dynamic range

8. XRD experiment by the SOPHIAS detector
BL-8A
Camera length ～150 mm
Sample location
X-ray
Sample is in front of
the SOPHIAS
SOPHIAS on the
IP diffractometer

9. XRD experiment by the SOPHIAS detector
Sample : SmBaMn2O6
Material property
・ Changes in the ferroelectric in
the transition phase
in XRD measurement,
normal phase → 1 peak
transition phase
→ Split into very close 2 peaks
Phys. Rev. B (R) (2014)

10. XRD experiment by the SOPHIAS detector
EX-ray = 18 keV
1-D transformation
by circular integration

11. XRD experiment by the SOPHIAS detector
IP (100 μm square pixel)
SOPHIAS
Camera length ～190 mm
Camera length ～150 mm
SOPHIAS had disadvantage in camera length but made good result!

12. Outline ・ Introduction ・ XRD experiment by the SOPHIAS detector
・ Evaluation of the counting type pixel
・ Summary

13. Evaluation of the counting type pixel
Collaborative research between IHEP and KEK.
Development of the pulse-counting-type fine pixelated X-ray detector
based on Double-SOI technology.
TEGs
CPIXTEG3b (IHEP) : 50 μm square pixel, 64×64 array
Under evaluation.
CPIXPTEG1 (KEK) : 64 μm square pixel, 32×32 array
Now suspended.
Each pixels has just one contact to Middle-SOI layer.
→ does not work enough.
⇒ In this winter, CPIXPTEG2 will be rollout.
It has many contacts.

14. Evaluation of the counting type pixel
BL-14A
10 μmφ beam mode
TEG chip
CPIXTEG3b
/CPIXPTEG1
X-ray
pin-hole
X-ray filter
Ionization chamber

15. Evaluation of the counting type pixel
BL-14A
Flat field beam mode
Scattering target
(Glassy carbon)
X-ray

16. Evaluation of the counting type pixel
Recovery from the total ionization dose (TID) effect by use of
Middle-SOI.
Typical pulse shape of the Shaper amp. of CPIXPTEG1.
TID effect
require some voltage to Middle-SOI
Middle-SOI 0 V
Middle-SOI -1 V
(Before X-ray exposure)
Shaper pulse was recovered.

17. Evaluation of the counting type pixel
CPIXTEG3b
CSR calibration
The discriminator can be adjusted by 4-bit CSR on each pixels.
S-curve before/after CSR calibration using a pulse generator
Before calibration
After calibration
Counts
Input pulse height (mV)

18. Evaluation of the counting type pixel
Mean distribution of S-curves
Before
After
Numbers of pixel
σ value became better to about 5 times.
Before : 4.57 mV → After : 0.95 input pulse height

19. Evaluation of the counting type pixel
Before
After
Check by the flat field X-ray beam
In the test of threshold level scan with flat field X-ray, threshold
dispersion became half by CSR calibration.
Before : 26 nA → After : 14 level

20. Evaluation of the counting type pixel
1-dimensional pixel array scan by 10 μmφ beam
EX-ray = 16 keV, VHV = -120 V, exposure time = 2 sec 1 2 3 4
・ : Maximum counts in pixel array
・ : Total counts of all pixels
・・・・ : Counts of each pixels

21. Evaluation of the counting type pixel
Fitting by f(x) = p0 * Freq( ( x-p1 )/p3 ) * ( 1-Freq( ( x-( p1+p2 ) )/p3 ) )
p2 : size of a pixel (μm)
～ 45 μm
→ 5 μm smaller
due to shortage of the
charge collection efficiency
in peripheral area of the pixel.
p3 : degree of the charge sharing
(μm)
～ 6 μm

22. Evaluation of the counting type pixel
2-dimensional pixel array scan by 10 μmφ beam
Very low sensitivity in
corners of a pixel.
Charge was shared in
4 pixels.
Edge of the
pixel array
Row 63
Row 62
Row 61
Black line : boundary of the pixel

23. Evaluation of the counting type pixel
2-dimensional pixel array scan by 10 μmφ beam
Very low sensitivity in
corners of a pixel.
Charge was shared in
4 pixels.
CNPIX1 (Arai-san’s talk)
hexagonal shape and
prevents to charge
sharing effect.
This is expected to solve
the problems of the
square pixel.
Edge of the
pixel array
Row 63
Row 62
Row 61
Black line : boundary of the pixel

24. Summary XRD experiment by the SOPHIAS detector
SOPHIAS succeeded to separate very close 2 peaks with 150 μm
camera length. On the other hand, IP failed to separate although it had
advantage in camera length.
→ Fine size pixel is an important tool, especially in the experiment
where camera length is limited in short distance.
Evaluation of the counting type pixel
X-ray tests of the CPIXTEG3b/CPIXPTEG1 were done in KEK/PF.
It was noticed that the peripheral part of the pixel had low sensitivity
to X-ray.
→ CNPIX1 prevents this problem. The X-ray test for it will be planed
end of FY2016 (more happy case, end of this year).