medipix3 test set up

PREPARING THE NEXT GENERATION OF HYBRID

PIXEL DETECTOR READOUT CHIPS

M. Campbell, J. Alozy, R. Ballabriga, E. Frojdh, E.H.M. Heijne,

X. Llopart, T. Poikela, E. Santin, L.Tlustos, P. Valerio and

W.Wong

CERN, EP Department

1211 Geneva 23

Switzerland

Disclaimer

• This talk will NOT cover:

– Developments for ATLAS and CMS hybrid pixel detector

readout in 65nm (RD53)

– Work on monolithic pixel detectors (HV/HR CMOS etc)

-3- 3

Outline

• Hybrid pixel detectors

• Some chips from the Medipix family

• Timepix

• Timepix3

• A few examples of non-HEP applications

• CLICpix

• Progress with TSVs

• Conclusions

-4- 4

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/

• 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

The Medipix3 Collaboration

-6- 6

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

p+

n-

ASICn-well

p-substrate

Semiconductor

detector

Bump-bond

contact

Charged particle

gm

Iin Vout

-7- 7

Micro-channel plate readout

MCP can be used to detect electrons, ions or neutrons (when e.g. B doped)

-8- 8

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

H. van der Graaf et al

-9- 9

Hybrid pixel detectors

• Developed initially for LHC

• 3 large scale vertex detector systems operating smoothly

• One large RICH detector system (based on hybrid pixels

in a photodetector tube) contributing to LHCb physics

• In the Medipix2 and Medipix3 Collaborations we have

taken the technology into many new fields

• This talk reviews the status of the Medipix developments,

synergetic developments with CLICdp and briefly

outlines some future plans

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

* Chip designed at CERN, Nikhef and Bonn

-11- 11

Pixel matrix 256 x 256

Pixel size 55 x 55 μm2

Technology CMOS 250 nm

Charge collection polarity +ve or –ve (programmable)

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 Specifications

-12- 12

Pixel matrix 256 x 256

Pixel size 55 x 55 μm2

Technology CMOS 130 nm

Charge collection polarity +ve or –ve (programmable

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 40 Mbits/s – 5.12 Gbits/s

Maximum count rate 0.4 Mhits/mm2/s (data driven mode)

TOA Precision 1.56 ns

Front end noise 60e- RMS

Minimum threshold ~500 e-

Timepix3 Specifications

-13- 13

Timepix miniaturised readout

IEAP/CTU, Prague

-14- 14

CERN@school

Simon Langton School, Canterbury, England

-15- 15

CERN@school status August 2015

http://cernatschool.web.cern.ch/participating-institutions

-16- 16

Annual CERN@school Symposium

Langton student Katherine Evans

presenting at the CERN@school

Symposium in September 2014

-17- 17

Image of the astronaut Chris Cassidy working near the Timepix USB on the

International Space Station (Courtesy of NASA, photo ref. no. iss036e006175)

-18- 18

Timepix - 4s exposures

South China Sea South Atlantic Anomaly

University of Houston, IEAP Prague, NASA

-19- 19

0.3 mGy/d

3 mGy/d

5.5 mGy/d

REM Dose Rate Data (mG/min)

University of Houston, IEAP Prague, NASA

-20- 20

2 TIMEPIX chips inside the BIRD (Battery-operated

Independent Radiation Detector)

Timepix chip

ORION test flight

-21- 21

EFT-1 Dose-Rate (mG/min) Along the Trajectory

Courtesy of Ryan Rios, NASA, JSC

Space Radiation Analysis Group

-22- 22

A few examples of Other applications

-23- 23

Time of Flight Mass Spectrometry

“Enhanced Detection of High-Mass Proteins by Using an Active Pixel Detector”,

Shane R Ellis et al, Angewandte Chemie DOI: 10.1002/anie.201305501

-24- 24

Time of Flight Mass Spectrometry

“Enhanced Detection of High-Mass Proteins by Using an Active Pixel Detector”,

Shane R Ellis et al, Angewandte Chemie DOI: 10.1002/anie.201305501

-25- 25

Low Energy Electron Microscopy

I. Sikharulidze, J-P Abrahams and co-workers

‘Medipix2 applied to low energy electron microscopy’, Ultramicroscopy 110

(2009) 33 - 35

MCP + CCD

imagesMedipix2 Images Graphene flakes

-26- 26

InGrid Applications

Slide courtesy of K. Desch, Univ Bonn

-27- 27

CAST Calibration

Slide courtesy of K. Desch, Univ Bonn

-28- 28

Applications not covered

• ATLAS radiation monitoring

• Beam profile monitoring at SPS

• Beta radiography

• Characterisation of novel sensor materials/structures

• Dosepix

• Electron cryo-microscopy

• Electron emission channelling at ISOLDE

• Gamma camera

• Hadron therapy beam and dose monitoring

• LHCb VELOpix – based on Timepix3

• Neutron imaging

• Nuclear waste monitoring @ CERN (55Fe)

• UA9 beam profile monitoring

-29- 29

Energy and time measurements with

cosmic particles

-30- 30

Cosmic ray in Timepix3 - Measurement

Precise arrival time information (1.6ns steps) provides depth

of interaction within the sensor layer

Bias 100V, Ikrum 5, with time walk correction

-31- 31

Note: Not to scale!

Bias 100V, Ikrum 5, with time walk correction

5 mm5 mm

300 mm

Cosmic ray in Timepix3 - Reconstruction

-32- 32

Tracks with low bias voltage

Bias 20V, Ikrum 5, with time walk correction

-33- 33

Aegis Experiment

Slide courtesy of H. Holmestad, Univ Oslo

ToT information

-34- 34

Aegis Experiment

Slide courtesy of N. Pacifico, Univ Oslo

ToA information

-35- 35

Use of Timepix and Timepix3 by CLICdp

• Timepix and Timepix3 are available in wafer form and with (in the case of

Timepix) very well characterised readout systems

• Both devices have been used to study the behaviour of different sensor

types:

– p+ on n

– n+ on p

– Different suppliers

– varying thickness (300um, 200um, 100um, 50um)

– Different edgeless topologies

• See talk tomorrow by Nilou ALIPOUR

-36- 36

Timepix telescopes at CERN

2 particle telescopes have been installed at the CERN

SPS:

LHCb telescope used for evaluating irradiated sensors

in the context of the VELOpix R and D

CLIC telescope used to evaluate novel tracking

sensor hybrids for CLIC

Both telescopes use every particle which traverses

the telescope – 1TB/day…

Pointing resolution << 5mm (consistent with 55 mm

pixel pitch, tilted planes and analog readout

-37- 37

Timepix telescopes at CERN

-38- 38

Timepix telescopes at CERN

2 particle telescopes have been installed at the CERN

SPS:

LHCb telescope used for evaluating irradiated sensors

in the context of the VELOpix R and D

CLIC telescope used to evaluate novel tracking

sensor hybrids for CLIC

Both telescopes use every particle which traverses

the telescope – 1TB/day…

Pointing resolution << 5mm (consistent with 55 mm

pixel pitch, tilted planes and analog readout

-39- 39

CLICpix

• CLICpix is a hybrid pixel detector to be used as the CLIC vertex detector

• Main features:– small pixel pitch (25 μm),

– Simultaneous TOA and TOT measurements

– Power pulsing

– Data compression

• A demonstrator of the CLICpix architecture with an array of 64x64 pixels has been submitted using a commercial 65 nm technology and tested

• The technology used for the prototype has been previously characterized and validated for HEP use and radiation hard design*

*S. Bonacini, P. Valerio et al, Characterization of a commercial 65 nm CMOS technology for SLHC applications, Journal of Instrumentation, 7(01):P01015–P01015, January 2012

1.85 mm

3 m

m

-40- 40

“Moore’s law” for pixel detectors

0.01

0.1

1

10

00.10.20.30.40.50.60.7

CMOS process [µm]

Tran

sist

or

den

sity

per

pix

el a

rea

[tra

nsi

sto

rs/µ

m2]

Medipix1 (1998)

Medipix2 (2002)Timepix (2006)

Medipix3RX

(2012)

Timepix3 (2013)

CLICpix (2013) – 65 nm

-41- 41

A simple block diagram

Data INData

OUT

Analog part of adjacent pixels share biasing lines. Digital part is shared between each two adjacent pixels

64x64 pixel matrix

Chip periphery

-42- 42

Pixel architecture

• The analog front-end shapes photocurrent pulses and compares them to a fixed (configurable) threshold

• Digital circuits simultaneously measure Time-over-Threshold and Time-of-Arrival of events and allow zero-compressed readout

Inpu

t

CS

A

4-bit Th.Adj

DAC

Feedback

network

Polarity

TOA ASM

TOT ASM Clk divider

4-b

it T

OT

co

un

ter

4-b

it T

OA

co

un

ter

HF

Bottom pixel

Top pixel

Configuration data:

Th.Adj, TpulseEnable,

CountingMode, Mask

Threhsold

Vtest_pulse

Clock

-43- 43

TOT measurements

TOT gain variation is 4.2% r.m.s.

Tested for nominal feedback current

Corners have lower TOT gain

TOT integral non-linearity for different

feedback currents was tested

TOT dynamic range matches

simulations

-44- 44

Threshold equalization

• Routines for equalizing the threshold using the pixel calibration DACs were implemented, finding the noise floor for all pixels

• Calibrated spread is 0.89 mV (about 22 e-

assuming a 10 fFtest capacitance) across the whole matrix

-45- 45

Noise characterization

• Threshold scans

through the baseline

voltage were used to

calculate the noise floor

• There is a small pattern

effect due to the

different routing of pixels

in the double column

• Average noise is 1.96

mV r.m.s. (about 51 e-

assuming a 10 fF test

capacitance)

-46- 46

Measurement summary

Simulations Measurement

Rise time 50ns

TOA Accuracy < 10 ns < 10 ns

Gain 44 mV/ke- 40 mV/ke-

Dynamic Range up to 40 ke-

(configurable)

up to 40 ke-

(configurable)

Non-Linearity (TOT) < 8% at 40 ke- < 4% at 40 ke-

Equivalent Noise ~60 e- (without

sensor capacitance)

~51 e- (with a 6%

variation r.m.s.)

DC Spread

(uncalibrated)

σ = 160 e- σ = 128 e-

DC Spread

(calibrated)

σ = 24 e- σ = 22 e-

Power

consumption

6.5 μW 7 μW

Measurements

expressed in

electrons depend

on the test

capacitance. A

nominal value of

10 fF was

assumed here

-47- 47

Tests with detectors

• Calibration with radioactive sources, test pulses

and beams have been carried out using CCPDv3

sensors glued to CLICpix

• Systematic studies of gluing uniformity and

alignment

• Chip could be well characterized (See: Steven

Green et al. LCWS 15)

• For results using planar sensors. Please see

Magdalena MUNKER’s talk tomorrow

-48- 48

Tests with detectors

• Calibration with radioactive sources, test

pulses and beams have been carried out using

CCPDv3 sensors glued to CLICpix

• Systematic studies of gluing uniformity and

alignment

• Chip could be well characterized (See: Steven

Green et al. LCWS 15)

• For results using planar sensors. Please see

Magdalena MUNKER’s talk tomorrow

-49- 49

Tests with detectors

• Calibration with radioactive sources, test pulses

and beams have been carried out using CCPDv3

sensors glued to CLICpix

• Systematic studies of gluing uniformity and

alignment

• Chip could be well characterized (See: Steven

Green et al. LCWS 15)

• For results using planar sensors. Please see

Magdalena MUNKER’s talk tomorrow

-50- 50

CLICpix2

• Chip 4 times larger (128 x 128 pixels)

• A few bug fixes

• Maintain 2x8 superpixel structure

• Increased number of TOT bits 4->5 bit

• Increased number of TOA bits 4-> 8

• For status please see talk of Pierpaolo VALERIO

tomorrow

-51- 51

Tiling larger areas

Single chip assembly

Sensor

ASIC

-52- 52

Tiling larger areas – present day solution

ASIC

SensorLadder – n x 1

-53- 53

Tiling larger areas– present day solution

ASIC

ASIC

Ladder – n x 2

-54- 54

Tiling larger areas– present day solution

-55- 55

Tiling larger areas - TSVs at periphery

TSVs for IO eliminate wire bonding reducing dead area

-56- 56

Tiling larger areas - TSVs within pixel matrix

If IO are distributed within the pixel matric TSVs permit seamless tiling

-57- 57

Tiling larger areas - TSVs within pixel matrix

Permits use of single 4-side buttable tiles

-58- 58

Through Silicon Via processing of

Medipix3/Timepix3

Through Silicon Vias offer the possibility of creating 4-side buttable tiles

3 projects for been undertaken with LETI

- Funding mainly from Medipix3 Collaboration, AIDA and LCD group

1) 2011 - Feasibility of TSV processing on Medipix3 (low yield wafers)

2) 2013 - Proof of yield using Medipix3RX wafers (6 wafers)

3) 2014 - TSV processing of ultra-thin Medipix3/Timepix3 wafers

(50mm)

-59- 59

TSV processing on the Medipix3

MEDIPIX3 pixel side native thickness TSV processed chip“BGA” bottom

distribution

-60- 60

First image of Medipix3

TSV processed chip bump bonded to 300mm thick Si sensor

-61- 61

Sensor 500mm

(edgeless)

Chip thinned to

120mmWire bond for sensor HV bias

Sensor 200mm

Chip 750mm

Wirebonds for sensor HV biasASIC wire bonds

TSVs on Medipix3RX

TSV: CEA-Leti, FR

Flip chip: Advacam, FI

-62- 62

Dimensional Limitations of Present TSV Process

Process

does not

cover full

wafer

-63- 63

Yield verification of TSV Processed Wafers

-64- 64

Yield from 2nd TSV Project with LETI

Lot no. uSA999P Lot no. uSB254P

P04 P05 P06 P01 P02 P03

% KGD before TSV (on wafer) 57 51 50 50 60 53

% KGD after TSV (chips) 45 41 rework 20 41 38

-65- 65

Photo comparing 50mm and 120mm thick

Medipix3RX Chips with TSV Processing

50mm 120mm

-66- 66

What’s next for the Medipix family?

• A new Collaboration called Medipix4 is in formation

• Chips to be fully 4-side tile-able

• 2 chips development are foreseen:-

• Medipix4 Photon counting spectrometric chip– Will use charge summing and allocation scheme

– Multiple thresholds

– Pixel pitch varied to match sensor material

– Better high count rate performance (aimed at human CT)

• Timepix4– Smaller pixel pitch

– Better timing resolution (sub-ns)

– Better high count rate performance (TSV)

-67- 67

What’s next for CLICdp

• CLICpix2 to be submitted shortly

• We have developed a chip (called C3PD) in AMS

180nm HV process which is CLICpix2 compatible

(see talk by Iraklis Kremastiotis of this morning)

• Evaluate CLICpix2 with C3PD and planar sensors

• Construct a low mass module based on CLICpix2

for power pulsing tests

• Construct a low mass multi detector module based

on thin (50mm) and TSV processed Timepix3

combined with thin (50mm) planar edgeless

sensors

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Summary

• Hybrid pixel detectors were developed to respond to a need at

the LHC – particle tracking in high rate environments

• In spite of their relatively high cost (driven by low volume bump

bonding) they remain the detector of choice in high rate

environments

• Timepix/Timepix3 proved the versatility of the technology for

multiple other applications

• Timepix3 demonstrates particle tracking in a single

semiconductor layer and has been used to construct an

extremely high rate beam telescope

• Both chips serve as technology platforms for novel sensor

configurations and this feature has been well exploited by CLICdp

(and others)

-69- 69

Summary (contd)

• CLICpix and CLICpix2 (65nm CMOS) are designed for combined

high spatial resolution and precision timestamping @ CLIC

• C3PD (180nm HV CMOS) will serve to evaluate CLICpix2

• Progress with TSV technology demonstrated using

Medipix3/Timepix3 indicates that 4-side tile-able chips are

feasible

• The Medipix4 Collaboration (which is in formation) will fully

explore the design of 4-side tile-able readout chips for the first

time

• The Medipix3 and the future Medipix4 Collaborations will

continue to work in synergy with the CLIC vertex community

-70- 70

Thank you for your attention!

Medipix3RX images: S. Procz et al.