Wir schaffen Wissen – heute für morgen

24.10.13PSI, 24.10.13PSI,

Paul Scherrer Institut

Jungfrau, Mönch and Eiger:Detector Development at the Swiss Light Source

Aldo Mozzanica, Bernd Schmitt

Seite 2

Overview of the detector families

Single photon counting and charge integrating

The Eiger detector

The Jungfrau detector

The Mönch detector

Conclusions

Outline

Seite 3

PSI East

PSI West

Aare

SLS

PAUL SCHERRER INSTITUT

~1500 Staff employees; 30Km from Zurich, task in ETH domain: run large scale user facilities

Swissfel

720m

User facilities:uSR, SINQ, SLS

Seite 4

Swissfel start of construction

Seite 5

Swiss Mountains

Eiger Mönch Jungfrau(3970 m) (4099 m) (4158 m)

Other famous mountains: Mythen and Pilatus…

Seite 6

Swiss Detectors

Eiger Mönch Jungfrau75 µm pixel 25 µm pixel 75 µm pixel

Other swiss detectors: Mythen and Pilatus…

Single photon counting Charge integrating, gain switching Charge integrating,Dynamic gain switching

Frame rate 24k Hz few kHz 2 kHz

500k one module9M for CSAXs

Not yet defined 500k one module16M for SwissFEL

Seite 7

X-ray Detector Development at SLS

Seite 7

Integrating (FEL) SystemsIntegrating (FEL) Systems

Mythen II Eiger GotthardAGIPD:EU-XFEL

Jungfrau:SwissFEL

X-ray free-electron laser detectors

Synchrotron detectors

vthNumber of photons

Single photon counting

Total number of electron-hole pairs

Charge integrating detectors

and Synchrotrons

Mönch

Seite 8

From single photon counting detectors at PSI…

MYTHEN1k to 30k 50μm strips for

powder diffraction, small angle scattering, medical imaging…

PILATUS100k to 6M 172μm pixels

for protein crystallography, small angle scattering, imaging …

EIGER500k to 9M 75μm pixels, for small angle scattering, CDI, XPCS, protein crystallography, imaging ....

Threshold

+1

Amplifier and

shaper

Sensor Comparator CounterDigital output

Threshold

+1

Amplifier and

shaper

Sensor Comparator CounterDigital output

+1

Threshold

+1

Amplifier and

shaper

Sensor Comparator CounterDigital output

Seite 9

… to charge integrating detectors

Amplifier and reset

SensorSample

and hold External

ADC Analog output

main challenge for detector development:• dynamic range 104 12keV photons per pixel

• still with single photon resolution

Solution: dynamic gain switching

Gain switching

10 ms10 ms 10 ms10 ms

10101111 X-ray photons X-ray photons<<100 fs100 fs

Seite 10

Single photon counting hybrid pixel detector for synchrotron applications aimed towards diffraction experiments

• Applications at CSAXs:– Scanning Coherent Small Angle X-ray Scattering– Coherent Diffractive Imaging– X-ray Photon Correlation Spectroscopy

• Protein Crystallography

The Eiger Detector

Protein Crystallography

PILATUS 6M

PILATUS 2M

Coherent Small Angle X-ray Scattering

PILATUS 2M

EIGER

Seite 11

Front View

Side view

– Single photon counting pixel detector

– Sensitive area of 38 X 77 mm2

– Pixel size 75 µm

– 524k pixel module

– Dead time free mode of operation

– Maximum frame rates• 23 kHz in 4 bit mode• 12 kHz in 8 bit mode• 8 kHz in 12 bit mode

– 8 GB of memory on a module– Two 10 GbE data links per module

Half module image

Eiger, the next generation pixel detector

First full module diffraction pattern

, SRI2013 24.10.13Bernd Schmitt Seite 12

Number ofpixels

On board storage(frames/4 bits)

Data rate1

@ 12 kHzData rate2

@ 1kHData rate3

@ 100 HzData rate4

@ 10 Hz

Module 524 k (512 x 1024) ~32,740 50.3

Gb/s6.29 Gb/s*

839 Mb/s*

168 Mb/s*

9M Detector

9.44 M (3072x3072)

~32,740 906 Gb/s 113 Gb/s 15.1 Gb/s* 3.02 Gb/s*

1) 8 bit, equivalent to ~4@23 kHz and 12@8 kHz. 2) 12 bit. 3) 16 bit. 4) 32 bit. *) Foreseeable continuous storage rates (~20 Gb/s).

Eiger systems

500k single module Multi-module detectorEiger 9M

Seite 13

Noise and threshold dispersion

Operation Mode

Noise(e-) Sigma (e-)

LowNoise

121.1±0.07

10.7±0.06

Standard 160.1±0.08

13.9±0.07

Fast 185.0±0.1 18.7±0.09

@14KeV

Threshold Dispersion

Trimmed σ=67 eV

Untrimmed σ=479 eV

Seite 14

Rate Capability

E

I

Monochromatic X-rays

t (200 ns/div)

FastStandard

Low Noise

Simulated

+1 +1 ≠ 3

Threshold @ ½ Energy

High rate detection Eff. for 12 keV X-rays

Rate correction for 12 keV X-rays

Adj. Gain

Seite 15

On board Intelligence (data processing in firmware)

– On board data processing is in parallel on multi-module systems

• independent of the detector size• for modules reduces tens of Gb/s at the source• for a 9Ms, hundreds of Gb/s at the source

– Data buffering (8GB of memory)

– On the fly image summation• extends the dynamic range from 4096 to 4x109

• makes high flux continuous data taking possible• combined with rate correction

– Rate correction• performed on sub-frames @ kHz frame rate• more precise, less sensitive to rate fluctuations

– Pump and probe series averaging• high frame rate exposure series summing• alternating pumped and un-pumped

– Data reduction• 2x2 pixel rebinning• SAXS ring intensity averaging (planned)• data compression (question of HDF5 compatibility)

Rebinning

Series averaging

Rate correction

Image summation

Data buffering

Seite 16

High frame rate experiment

Eiger (30 sec )Point detector/ALV (300 sec)

50,000 diffraction patterns in 2.5 seconds,20 kHz, 45 μs exposure and 5 μs dead-time.

Dynamic

Studied the dynamics of a colloidal suspension

IntensityAutocorrelation function

Form and Structure factors

Relative motion between the scatterers

(82 nm radius silica colloids)

Structure factor S(q) with SAXS

Diffusion coefficient D(q) via XPCSNormalized field correlation function

Average of the diffraction patterns

“Capturing dynamics with Eiger, a fast framing X-ray detector”I. Johnson et al., J. Synchrotron Rad. (2012). 19, 1001

Siegert relation,

Seite 17

An Eiger self portrait (Ptychography)

Diffraction patternfrom one ½ of a module

Object: An Eiger readout chip

• The object is raster scanned with an out of focus beam• Diffraction patterns at overlapping positions on the object are recorded• The information in the overlap is used to recover the phase• Both the attenuation and phase shift in the object can be reconstructed

x (um)

y (u

m)

Phase image

OSA

Object

FZP

Coherent X-rays

Seite 18

Jungfrau: a 2D detector for Swissfel

appearance of a single module

Sensor 8x4cm2

8x ASIC

ADCs 40ch

GOTTHARD like readout

board

2x 1Gbit link

• ASIC and readout system based on GOTTHARD:

• 3 gains automatic switching

• Low noise high dynamic range (104 12keV

photons)

• Dimensions, sensor and mechanics from EIGER:

• 75 x 75 µm2 pixel size

• 4 x 8 cm2 sensor size

• Frame rate: 2kHz

adadJUJUstistiNNgg GGain detector ain detector FFooR R the the AAramis ramis UUserser stationstation

Seite 19

Preamplifier with gain switching

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000

0

100

200

300

400

500

600

Number of the input photons

ou

tpu

t vo

ltag

e (

mV

)

Logic after comparator to:

Switch a 2nd time if 1st switch not enough

Avoid a 2nd switch on spikes due to the 1st one

Switching has to be FAST (<10ns)

Simulation data

CSA in charge integrating configuration

3 feedback capacitors

Common for 1D and 2D, baseline for

AGIPD, Gotthard and Jungfrau

Seite 20

Jungfrau pixel architecture

Basically a 2D version of Gotthard

In a pixel design the following challenges are present:

• Size reduced by a factor 5

• Power consumption per channel reduced by x50

• low power preamp and CDS

• power cycled off-pixel buffer

• Space for feedback capacitor limited,

• amplifier range optimization

• precharge of feedback capacitors

prototype pixel layoutwork in progress

switch. + precharge

logic

preamp

comparator

CDS

pixel buffer

storage cells 16x

MIM feedback cap. covering the whole area

Jungfrau radout architecture

Seite 22

Dynamic gain switching response

• measured with internal current source (for this plot)

•1st gain switch at 25 ph. , 2nd at 600

• Linear up to >9500 12keV ph.

• Linearity err. <1%

Seite 23

First prototype

Prototype with 48 x 48 pixels

Bump bonded to sensor

Tested with X-rays and laser

2 problems identified

Second prototype received in October

A.Mozzanica PIXEL2010

Seite 24

First measurements

Noise for Jungfrau: 120 electrons (r.m.s.)

Noise map

noise tail coming from RTN

, SRI2013 24.10.13Bernd Schmitt Seite 25

Noise with dynamic gain switching

Dynamic range104 12 keV photons

Noise always belowPoisson limitSingle photon countingData quality

Seite 26

Gain switching measured with ps optical laser

laser spot size~3µm

Low intensitty

HIGH intensitty: switching

Seite 27

Linearity can be bad...

..if hundreds of channels are irradiated with a similar intensity

When many channels are near the switching threshold, power consumption of the comparators induces a local voltage drop on the power supply lines

Simple redesign can fix the issue.

Seite 28

The second Jungfrau prototype

● Preamplifier variations to understand the RTS noise

● Redesign in the digital part of the comparator to reduce power consumption near switching point

● Inmproved digital logic, 2bit digital latch per storage cell

● Protection diodes and tiedown.

● Improved output buffer and power distribution

● Prototype under test, not yet hybridized.

Seite 29

Swissfel beamline layout

ESA

ESB

ESA: multi purpose pump probe for systems in solution• nanocrystal diffraction using a liquid jet system• X-ray absorption (XANES, EXAFS)• X-ray emission (XES, RIXS)• Diffuse scattering (SAXS, WAXS)

•X-rays 2-12.4 keV

• 2 16M Jungfrau detectors

ESB: femtosecond X-ray pump rpobe diffraction and scattering on bulk crystals and films

•X-rays 5-12.4 keV

• 1 16M Jungfrau detectors

Seite 30

Plans and summary for Jungfrau

• Single modules 500K 4x8 cm2

• 4M 2x4 modules 16x16 cm2 (as a portable system)

• 16M 4x8 modules fixed hole in vacuum for SwissFEL

• 16M variable hole out of vacuum for SwissFEL

•Timeline:

• Full chip beginnig of 2014

• module 2014

• detector mid 2015

Eiger

Jungfrau

Seite 31

Benefits of Jungfrau

Small pixel size: 75 microns

High frame rate: >2kHz

High linear count rate capability:

• Dead time free 24MHz per pixel

• Quasi infinite for smaller integration times

• First not count rate limited hybrid pixel detector

Low noise of 120 e- (434 eV) low energies accessible:

• 3 keV with single photon resolution

• Less without single photon resolution

(sensor with thin entrance window)

High energies with scintillators

extremely good detector also for synchrotrons

The Mönch detector

•25 x 25 µm2 pixel integrating detector

• currently research project (no big system defined yet)• prototype with 160 x 160 pixels• goal: low noise and high dynamic range thanks to the dynamic gain switching

•At single photon rates • Interpolation gives 1 µm position resolution• Spectral information is available by summing cluster charges

•Applications• Tomography• Laue Diffraction • Imaging using X-ray tubes

– Low rates, 1µm position resolution + energy resolution

MMicropixel with enhanced picropixel with enhanced pOOsition rsition rEEsolution usisolution usiNNg g CHCHarge integrationarge integration

C1

C2

Discr.

Contr

ol lo

gic

Vthr

CDS.

Mönch pixel schematics

160 x 160 pixels divided into 4 groups:

• group 1+2 fixed gains• gain1: 15 12keV photons• gain2: 100 12 keV photons

• group 3+4 dynamic gain switching• gain1: 15 12 keV photons• gain2: 600 12 keV photons

• CDS gain 1 and 4

Seite 34

The Mönch detector bump bonding

Pilatus 172 um Eiger 75 um Mönch 25 um

• Bump bonding of 25 micron pixel seems doable with PSI in-house process

• Need to work on photo lithography (optimization of masks)

x5.3 x47

Seite 35

Preliminary noise Distribution

we have to measure and understand the variouscontributions but evensmaller noise seems possible

Seite 36

Cluster charge Distribution

Seite 37

50% 50%

Position dependent charge sharing

Seite 38

50% 50%

Position dependent charge sharing

Seite 39

Gotthard: position interpolation I

To measure the spatial resolution a 2µm W slit has been

scanned in 1µm steps in front of the strips

slit parallel to strips

Vertical beam size ~100µm

Strip pitch 20µm, 15keV beam

reconstructed vs motor positions

residuals distribution (PSF)2µm W slit

σ=1.8µm

X motor stage1µm steps

rotary stagefor slit alignment

X motor stage1µm steps

JJ slits

Simulation (Geant+TCAD)

Mönch position interpolation

High contrast up to 15um Peak to peak

low contrast and alias effects

Seite 41

The Mönch detector possibilities and conclusion

Will put a 1cm x 1cm = 400 x 400 pixels = 160k chip on Jungfrau submission(end 13/beginning 14)

Will probably make a 2cm x 2cm = 800 x 800 pixels = 640k readout chip and systemFor tomography with a 2 micron resolution this gives 100M pixel detector

Chip size: up to 2.3x3.1 cm2; ~880x1200 (active=2.2x3)=1.056 Mpixels/chip

2 Mpixel

??

~6.2cm

~2.3cm

MODULE

Frame rate: 2.4 kHz

Control

½ readout pads

½ readout pads

CHIP

Seite 42

The Mönch detector possibilities and conclusion

We can bump bond 25 micron pixels

Mönch is currently the hybrid pixel detector with the smallest pixels

We have made a lot of progress in our understanding andability to think

Mönch has an extremely low noise • low energy hybrid detectors (400eV) seem possible• also an energy dispersive detector (a la Maia) seems possible

We will continue to work on interpolation• RIXS• Tomography

Ideal for ct with X-ray tubes (high resolution and color imaging)

Seite 43

Conclusions

Jungfrau will be the main dector for SwissFEL and probably similarly important forsynchrotrons where count rate limitations are important

We will have to work in the coming years to make calibration and usage ofcharge integrating systems easier (ideally todays single photon counting systems)On the long run part of the data processing will be moved in the firmware.

Hybrid pixel detectors with small 25 µm pixels are possible

Low energy hybrid pixel detectors are around the corner

Wir schaffen Wissen – heute für morgenWir schaffen Wissen – heute für morgen

The SLS Detector Group:Anna Bergamaschi, Roberto Dinapoli, Dominic Greiffenberg, Ian Johnson, Julia Jungmann Dhanya Maliakal, Aldo Mozzanica, Christian Ruder, Lukas Schädler, Bernd Schmitt, Xintian Shi, Gemma Tinti