New Detectors for Synchrotron Radiation Research: Higher Time and Spatial Resolution

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New Detectors for Synchrotron Radiation
Research Higher Time and Spatial Resolution
P. Denes1, C. S. Fadley1,2, B. Ludewigt1 1Lawrence
Berkeley National Laboratory, 2Dept. of Physics
UC Davis

• 1 and 2-D upgrades of current high-speed detector
  for electrons and photons (previous presentation
  by Bussat et al.) for time/space resolved
  spectroscopy/microscopy
• Pixel systems for protein crystallography
• Large-scale pixel systems - position and
  energy-resolving for very high count rate
  applications, e.g. for x-ray fluorescence
  holography

Capitalizing on large investment in IC/detector
development for high-energy physics
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Current ALS High-Speed Detector
Collector 50µ pitch
CAFÉ-M Si strip IC
BMC IC
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Upgraded, Higher-Speed 1-D Detector

• Very high-speed, deadtimeless readout for
  dynamics
• Increase system readout speed by factor 100
• Combine CAFE BMC into one CMOS IC
• New mechanical platform for 1-D and 2-D versions

• 2 µs to read complete detector in 8-bit mode
• 4 µs to read complete detector in 16-bit mode
  (for compatibility)
• 80 GHz theoretical maximum rate for detector (100
  MHz max/strip)

Semi-rigid coax
Gigabit serializer
200 channel ASIC
Applications Time-resolved photoemission and
x-ray absorption, incl. nanoscale magnetic
switching
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2-D Version of ALS High-Speed Detector
e?

• Monolithic detector
• Top layer of ASIC metalization serves as
  (pixellated) collector
• 10k counters/chip
• Gigabit link ? 100 Mbytes/s? 200 µs to read out
  system

MCP
Metal Pad
Screen
Discr.
Clt 100 fF
16-bit counter
Preamp
Thresh 5 ke?
shift register
1 pixel
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2-D Version of ALS High-Speed Detector
Active area 4 x 1 cm2
Pixel 50µ x 200µ
1cm
Gap ?200µ
Applications angle-resolved photoemissionx-ray
emission spectroscopy inelastic scattering
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Inside a Pixel

• CIN 70 fF (pad)
• QTHR 5k e?
• 1300 transistor/pixel
• CMOS 0.25µ
• 50µ x 200µ pixels
• 13M transistor/chip
• CMOS 0.13µ
• 50µ x 50µ pixels
• 55M transistor/chip

Test Pulse
Preamp Discriminator
Digital part (16-bit counter, shift register ...)
Envelope 50µ x 200µ
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3DX x-ray Detector - Protein Structure

• MEMS technology sensor
• Vertical collection electrodes (speed)
• Trench-cut edges (active edge)

Molecular Biology Consortium, LBL, U. Hawaii,
Brunel, Stanford
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3DX Detector

• Direct conversion (rather than scintillatorsCCD)
• Large area - 30x30 cm2
• Edgeless detector

• Prototype readout being submitted now in 0.25µ
  CMOS
• On-chip ADC
• 144x150 µ2 pixels

Prototype (8x64 pixel) Circuit
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X-ray Fluorescence Holography
Excitation x-ray
Detector

• Current Method
• Fixed, single-element detector
• Rotate sample in ?,?

SAMPLE
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XFH with Pixellated Detector
Excitation x-ray
Large area pixel detector (? 2?, ?? small, GHz
rate)
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Ideas from the ATLAS Pixel Detector
1.3 m
10 cm ? (Inner-most layer)
Cylinders are simpler than spheres! ATLAS pixel
8x107 Pixels
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XFH Detector
5 cm
Sensor - 2x2 cm2 Pixels - 1x1 mm2 ?? ? (1?)2 ?
90 x 2? 90 sensors 36000 pixels
20 cm
2 cm ladders
Applications Holograms in seconds or single XFEL
pulse simplified detector for XRD in single FEL
pulse
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Inside a Pixel
Trigger
R
W
PED
Preamp
ADC
W
RST
Peak Detector
Readout format

• 200-300 eV FWHM
• Adjustable shaping times
• 50 kHz / pixel
• 8-bit ADC / pixel
• Pedestal measurement mode

Time
Addr
ADC

• ADC value
• Geographical address
• Time stamp

Small detector compared to ATLAS (1/2000 as many
pixels) But data rate is challenge (gt5 Gbyte/s)
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Large-Scale Pixel Detectors are Complex Systems
100 mm wafer with 3 Si sensors
0.25µ CMOS Readout IC
18x160 pixels
Readout
Solder Bumps
50µm
A module is 1 sensor with 2x8 bump-bonded chips
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Conclusions

• Use knowledge gained in building strip and pixel
  systems for HEP. Not only in detector and IC
  design, but also in assembly and system
  integration
• Designs for building updated 1- and 2-dimensional
  spectroscopy detectors
• Plans for a large-area, energy-resolving pixel
  detectors for both protein crystallography and
  x-ray fluorescence holography/XFEL diffraction