1. The Medipix/timepix chip family
This is a test
The Medipix/timepix chip family
M. Campbell, J. Alozy, R. Ballabriga, E.H.M. Heijne, X. Llopart, T. Poikela, E. Santin, V. Sriskaran, L.Tlustos, and W.Wong
CERN, PH Department
1211 Geneva 23
Switzerland

2. The Medipix2 Collaboration
U INFN Cagliari
CEA-LIST Saclay
CERN Genève
U Erlangen
ESRF Grenoble
U Freiburg
U Glasgow
IFAE Barcelona
Mitthoegskolan
MRC-LMB Cambridge
U INFN Napoli
NIKHEF Amsterdam
U INFN Pisa
FZU CAS Prague
IEAP CTU in Prague
SSL Berkeley

3. The Medipix3 Collaboration
University of Canterbury, Christchurch, New Zealand
CEA, Paris, France
CERN, Geneva, Switzerland,
DESY-Hamburg, Germany
Albert-Ludwigs-Universität  Freiburg, Germany
University of Glasgow, Scotland, UK
Leiden University, The Netherlands
NIKHEF, Amsterdam, The Netherlands
Mid Sweden University, Sundsvall, Sweden
IEAP, Czech Technical University, Prague, Czech Republic
ESRF, Grenoble, France
Universität Erlangen-Nurnberg, Erlangen, Germany
University of California, Berkeley, USA
VTT, Information Technology, Espoo, Finland
KIT/ANKA, Forschungszentrum Karlsruhe, Germany
University of Houston, USA
Diamond Light Source, Oxfordshire, England, UK
Universidad de los Andes, Bogota, Colombia
University of Bonn, Germany
AMOLF, Amsterdan, The Netherlands
Technical University of Munich, Germany
Brazilian Light Source, Campinas, Brazil

4. Hybrid Silicon Pixel Detectors
Fill factor is 100 % (away from periphery)
Full depletion of sensor allows prompt charge collection
Extremely high SNR easy to reach
Standard CMOS can be used allowing on-pixel signal processing
Sensor material can be changed (Si, GaAs, CdTe..) or replaced (Microchannel Plate, GEM, InGrid…)
But because of low volumes bump bonding is still expensive
Mention signal generation Add X section?

5. Micro-channel plate readout
MCP can be used to detector electrons, ions or neutrons(when e.g. B doped)

6. Gas detector readout - InGrid
Semiconductor detector is replaced with charge amplification grid
Permits lower energy events to be detected
NB: GEM foils may be used in place of the InGrid foils

7. Medipix chips since 2000 Medipix2 (2002-2005)
First photon counting chip at 55mm pitch
Camera logic (shutter driven)
Window discriminator/pixel
Frame based readout (sequential read/write)
Timepix (2006)
Same IO as Medipix2
Possibility to programme pixels to count hits, record arrival time or ToT
Medipix3 ( )
First photon counting chip with charge summing and allocations scheme
Programmable sensor pixel pitch (55mm or 110mm)
Frame-based readout but possibility of continuous read/write
Timepix3 ( )
Fully data driven architecture
For each hit pixel coordinates, amplitude and arrival time are sent off chip

8. Medipix2 Specifications
Pixel matrix
256 x 256
Pixel size
55 x 55 μm2
Technology
CMOS 250 nm
Measurement modes
Single photon counting
# thresholds
2 per pixel with window discrimination
3-bit adjustment DAC per pixel
Counter depth
1 x 14-bits
Readout type
Frame based
Sequential R/W
Readout Time
Serial: <100ms at 100MHz
Parallel: 100MHz
Minimum threshold
~ 900 e-

9. High resolution X-ray imaging using a micro-focus X-ray source
Edges are enhanced
by phase contrast effect
Next, we used the detector medipix for imaging of animal tissue. In this picture we concentrated (konsentreit) on mouse kidneys. We were looking for presence of tumors in mouse kydney. The first picture presents the kidney without tumor cells. Also you can see different magnification. We clearly observe (ebzerv) the inside structure of kidney.
Needle holding the sample

10. Timepix Specifications
Pixel matrix
256 x 256
Pixel size
55 x 55 μm2
Technology
CMOS 250 nm
Measurement modes
Programmable per pixel:
Single particle counting
Timepix (arrival time wrt shutter)
Time over Threshold
# thresholds
1 per 55 μm pixel
4-bit threshold adjustment
Counter depth
1 x 14-bits
Readout type
Frame based
Sequential R/W
Readout Time
Serial: <100ms at 100MHz
Parallel: 100MHz
Minimum threshold
~ 650 e-

11. Timepix miniaturised readout
IEAP/CTU, Prague

12. Timepix chip – 60s exposures
Near sea level
feet

13. This is a test
Cross section of a Hybrid Pixel Detector system (X-ray photon energy deposition) g
Double counting or missing hits
Sensor dimensions to scale (55mm pixel pitch, 300mm thick sensor)

14. Fluorescence in high-Z materials
This is a test
Fluorescence in high-Z materials g gf
Energy resolution degradation AND missed or double counted hits
Picture to scale (55mm pixel pitch, 300mm thick sensor)

15. This is a test
The algorithm for charge reconstruction and hit allocation: Charge Summing Mode
Note
The analog charge reconstruction (no thresholding before summing).
That as long as the full charge is deposited in a cluster of 2x2 elements it will be correctly reconstructed.

16. Medipix3 Specifications
Pixel matrix
256 x 256
Pixel size
55 x 55 μm2 or 110 x 110 mm2
Technology
CMOS 130 nm
Measurement modes
Single pixel
Charge summing
Gain modes
Super low gain mode
Low gain mode
High gain mode
Super high gain mode
# thresholds
2 per 55 μm pixel
8 per 110 μm pixel
Programmable counter depths
2 x 1-bit
2 x 6-bit
2 x 12-bit
1 x 24-bit
Readout type
Frame based
Sequential R/W
Simultaneous R/W
Readout Time
Depends on counter depth used
Minimum threshold
~ 500 e-

17. Energy Response Function (CdTe 110mm/2mm)
~4.4KeV FWHM
Normalised differential counts
Energy (keV)
Slide courtesy of T. Koenig, KIT
T. Koenig et al., accepted for publication, IEEE Trans Nucl Sci 2013

18. Colour x-ray of a lighter
RGB:
9-50 keV
9-14 keV
14-23 keV
31-50 keV
S. Procz et al.

19. Timepix3 Specifications
Pixel matrix
256 x 256
Pixel size
55 x 55 μm2
Technology
CMOS 130 nm
Measurement modes
Simultaneous 10 bit TOT and bit TOA
bit TOA only
10 bit PC and 14 bit integral TOT
# thresholds
1 per 55 μm pixel
4-bit threshold adjustment
Readout type
Data driven
Frame based (both modes with zero suppression)
Dead time (pixel, data driven)
>475 ns (pulse processing + packet transfer)
Output bandwidth
80 Mhits/s – 5.12 Gbits/s
Maximum count rate
40 Mhits/cm2/s (data driven mode)
TOA Precision
1.56 ns
Front end noise
60e- RMS
Minimum threshold
~500 e-

20. Energy and time measurements with cosmic particles
Integral frame ~ 72h

21. Timepix3 Spectrum(Si 55mm/300mm)
3.76 keV FWHM
241Am
E. Frojdh

22. Energy and time measurements with cosmic particles
E. Frojdh

23. Cosmic ray in Timepix3 - Measurement
Precise arrival time information (1.6ns steps) provides depth of interaction within the sensor layer
E. Frojdh

24. Cosmic ray in Timepix3 - Reconstruction
300 mm
5 mm
5 mm
Note: Not to scale!
E. Frojdh

25. Summary Table
Medipix2
Timepix
Medipix3
Timepix3
Medipix4
Timepix4
Pixel side (mm) 55
55/110
70/140
≤ 55
Technology (nm)
250
130
65/130 65
# pixels in x and y
256
256/128
>256
Readout architecture
Frame based
Sequential RW
Continuous RW
Data driven/
frame based
Charge summing and allocation mode (CSM) No
Yes
# thresholds
2 (window discriminator) 1
2/4/8 Seq RW
1/4 Cont RW ?
ToT/ToA
ToT (14 bit) OR ToA (14 bit, 10ns precision)
ToT (10 bit) AND ToA (14 bit, 1.56ns precision)
ToT AND ToA
Front end noise
(e- rms)
110
100
80(SPM)
174(CSM) 62
≤ 80 (SPM)
≤ 174 (CSM)
≤ 62
Peaking time (ns)
150
120 30
≪120
≪30
Max count rate (Mc/mm2/s)*
826 -
826 (SPM 55mm)
164 (CSM 55mm)
376 (SPM 110mm)
28 (CSM 110mm)
0.43 (data driven)
x5 Medipix3
x10 Timepix3
Number of sides available for tiling 3 4 *
*Depends strongly on exact conditions of threshold, sensor material and energy of illumination
NB Parameters in blue are still being defined

26. Thank you for your attention!
Medipix3RX images: S. Procz et al.