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

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 http://medipix.web.cern.ch/MEDIPIX/

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

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?

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

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

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 (2009-2014) 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 (2014-2015) Fully data driven architecture For each hit pixel coordinates, amplitude and arrival time are sent off chip

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: <300ms @ 100MHz Minimum threshold ~ 900 e-

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

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: <300ms @ 100MHz Minimum threshold ~ 650 e-

Timepix miniaturised readout IEAP/CTU, Prague

Timepix chip – 60s exposures Near sea level 34 000 feet

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)

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)

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.

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-

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

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

Timepix3 Specifications Pixel matrix 256 x 256 Pixel size 55 x 55 μm2 Technology CMOS 130 nm Measurement modes Simultaneous 10 bit TOT and 14 + 4 bit TOA 14 + 4 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-

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

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

Energy and time measurements with cosmic particles E. Frojdh

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

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

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

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