Challenging Technology: Detectors Beyond the LHC

Craig Buttar Higgs Maxwell Meeting Feb ‘06

Examples – ATLAS SCT

Future of Particle Physics in a nutshell

• Luminosity upgrade of LHC (sLHC) – H self couplings  precision tracking in high multiplicity environment – Radiation hardness x10 cf LHC – Large scale production • LHCb upgrade – Velo replacement required after 3 years – LHCb data taking limited to 1/50 th of design luminosity – Make better use of LHC luminosity  new physics improve rare decay limits test • Precision physics at ILC – Higgs couplings, SUSY (Higgs) mass spectrum……..

– High resolution vertexing for flavour tagging – High resolution tracking calorimetry based on energy flow • The neutrino sector – Unravelling the neutrino mass matrix – Large scale detectors – Beam systematics

sLHC

Luminosity upgrade for ATLAS-SCT Tracking and b-tagging Design issues • layout • occupancy • radiation damage 50 m m pitch Neutron 18% Pion 74% Proton 8% Neutron 65% Pion 29% Proton 6% Neutron 66% Pion 25% Proton 7%

Pixels: r=6cm, 15cm, 24cm Ministrips: r=35cm, 48cm, 62cm Microstrips: r=84cm, 105cm

Si technologies for sLHC

• Si Traditionally use p-in-n detectors but cannot operate underdeplented • Use n-in-p as no type inversion – Production issues – HV required, careful design to avoid breakdown • Use Cz based n-type Si – Does not invert (?) – Now a common material in Si manufacture – Harder to charged particles  best for intermediate radii or pixels n-in-p

7000e -

SLHC R=40cm

P-type 1cm detector after 7.5×10 15 p cm -2 ≈ 4.5×10 15 1MeV n eq cm -2 (850V)

SLHC R=20cm Ionisation in oxide  + P current from cut edges + + Displacement damage cluster n  p; increased dark current guard region Detector region P-type Si CCE is now an issue ionisation  signal

W3D~20 m m W2D~300 m m

+ve -ve +ve

h +

p +

e -

W 3D

E

n +

3D detectors

e h +

+ve E

W 2D • 3D uses MEMS technology to engineering Si structures – Smaller detector ‘cells’  Lower depletion voltages  Faster and more efficient charge collection

BUT

small-scale suitable for LHCb upgrade For 4.5 x 10 14 24GeV/c p/cm 2 (2.7 x 10 14 1MeV n/cm 2 2 years LHCb Velo inner radius Depletion voltage = 19V Type inversion observed )

Other issues for sLHC

• Cooling – Thermal runaway: I  Power dissipation  T – To avoid thermal runaway need to have edges a -30 o C to dissipate heat and keep temp low – Current technology has a coolant temperature of ~-30 o C to give –7 o C at LHC – Low mass cooling with robust minimum mass pipes • Large scale production – SCT area 60m 2  210m 2 – Electronics 6M  60M channels – Need close links with industry for mass production of components and assembly?

-20 -25 -30 -35 -40 -45 0 2

Flux 2E15, bias 800, width 9cm

4

x (cm)

6 8 -44 degC -42 degC -40 degC -38 degC -36 degC -34 degC -32 degC -30 degC

LHCb upgrade triggering at LHC lumi

• Factor five higher lumi Cope 3-4 interactions per beam crossing • Muon trigger fine – 4 of 10 benchmark channels have m + m in final state • Hadron Trigger bandwidth saturates – Need displaced track trigger at first trigger level 8 FPGA based Triggering system – Pattern recognition / tracking – Primary Vertex Identification – Displaced Track Trigger – 4 m s latency

Vertex detectors for ILC

• Physics requirements – Identify b and c-jets and jet-charge – Momentum resolution s (1/pT) at 100GeV ~4-5TeV -1 for energy flow —see later (ATLAS 100TeV -1 ) important • Detector requirements – Very low mass – High resolution s ip ~3 m m  occupancy – Beam structure  ~20 m m pixels readout every 50 m  ~10 9 channels  reduces s ~20 times during 1ms train • Data readout – possible em interference • Data stored -- readout during ~0.2 between bunches – Radiation hardness less of an issue

ILC vertex detectors

• CCDs – Used in linear collider at SLAC -- SLD – Precision but readout speed is slow as reading out each column and then row – Readout each column – CPCCD • First prototypes CPC1 by LCFI – Readout at 25MHz – RF pickup from beam is a worry!

CPC1 RO chip (Bump bonding Packaging and interconnects)

Detectors with storage ISIS and MAPS

• ISIS – In-situ Storage Image Sensor – Store charge in 20-element CCD – Readout during 0.2s between bunches – Solves potential RF problem and is more radiation hard – But processing has to be demonstrated • Monolithic Active Pixel sensors – CMOS imaging technology – Smaller active volume – Requires development of on-chip memory

Calorimetry for the ILC

• Need to resolve W and Zs – Requires best achieved at LEP 60%

E



E E

1Gb x5000 5000 fibres – Need to measure energy flow in the event • Match charged tracks to clusters • • Measure neutral clusters in calorimeter  good spatial resolution – more important than energy resolution!

– Leads to a number of technical issues • Readout density and getting data out of the calorimeter: 0.3-3GBytes/s per ASIC, 200TByte/s total ECAL • Achieving the required spatial resolution -- MAPS • Managing the thermal load 10Gb Event Builder PC Large Network Switch/s 5Tb Event Builder PC Event Builder PC Si Wafers PCB VFE chip Tungsten x250 Cooling Target Control Event Builder PC Busy 8.5mm

Neutrino factory

• Golden channel muon appearance • Requires MINOS like detectors but x10 larger • The large volume leads to problems with reading out scintillator (~10m) • But need to understand the beam!

 m 50% 50% 

e

 m 

e

    

e

  m     m     

wrong sign muon

Large Magnetic Detector

20 m  beam

40KT

20 m B=1 T iron (4 cm) + scintillators (1cm)

Neutrino factory

• Near detector – Need to measure flux and charm background rates for measurements at far detector – Use active target – Large area coverage required (18 layers covering 50x50cm 2 – Use MAPS • 2D readout • Cheap large area coverage Si tracker in NOMAD

Not covered

• Development of technologies for PP is as active as ever • Too many to cover!

• Some topics not covered (still only a selection) – Rad-hard readout chips for sLHC – Development of ionisation cooling for nufact – MICE @ RAL – Fast feedback systems for ILC to optimise luminosity – Low background detectors for Dark Matter searches and neutrinoless double beta decay – Precision physics at LHC (FP420): Small scale tracking detectors able probe the edge of the beam – …..

Other applications

• Particle physics technology has found applications in – Radiotherapy – Imaging 2 mm Medipix 1 Imaging plate Medipix 2

Summary and conclusions

• Future Particle Physics experiments has many challenges for detectors and systems – Rad-hardness – Speed – Precision – Large scale production – Connections – System building detectors+readout  modules  subsystems – Data handling

Backup

LHCb Upgrade – Why ?

• LHCb uses only 1/50 th of LHC design luminosity – Average of one interaction per beam crossing – Limit Radiation damage • Many physics results would benefit from higher luminosity, e.g.

– Rare B decays • Clear Benefit • e.g. Bs m + m – SM BR 3.5 x 10 -9 , 3.7 s after 3 (10 7 second) years –  • Not theoretically limited after 3 (10 7 second) years • More (clean) events would help !

LHCb Upgrade -Technically Feasible?

• Radiation Hard Silicon Technology Developed •Czochralski Silicon •n-on-p •3D detectors •Hybrid Pixels Construct a Vertex Detector with •better proper time resolution •withstand 10 times more radiation damage First Velo need replacement ~ 2011 Priority only if large D m s 10 15 1 MeV neutron equiv. /cm 2 VE tex LO cator VE LO S uperior P erformance A pparatus

•New Triggering Strategy • Factor five higher lumi Cope 3-4 interactions per beam crossing • Muon trigger fine – 4 of 10 benchmark channels have m + m in final state • Hadron Trigger bandwidth saturates – Need displaced track trigger at first trigger level 8 FPGA based Triggering system – Pattern recognition / tracking – Primary Vertex Identification – Displaced Track Trigger – 4 m s latency

Plan

• Rad. Hard Sensors being produced •6” mask designed •MCz, n-on-p, pixels • Prototype VELO modules and Trigger 2009 • Upgraded VELO & displaced vertex trigger 2011

Physics case for future neutrino facilities

•

Neutrino oscillations for atmospheric, solar, reactor neutrinos provide fit to

• q

23 ,

q

12 ,

D

m 12 2 and

D

m 23 2 Need more experiments for

q

13 , mass hierarchy and CP violation phase

d

Super-beams

•

Super-beams (ie. JPARC beam for T2K) provide monochromatic off-axis neutrino beams for



e appearance

2.5

o

q

=2 o

q

=0 o

T2K

Goal T2K: down to

q

13 ~2-3 0

3 o Flux

    2 1    2 q 2    2

0 1 2 E



(GeV)

•

Proposals for super-beams with ~ Mton Water Cherenkov detectors (Memphys in Frejus, HyperKamiokande Japan, UNO in USA)

Beta-beams and neutrino factories

•

Beta-beam facility

2 6

He

   3 6

Li

   

e e

 18

Ne

10  18 9

F ν e e

 •

Neutrino factory:

Low-energy part Ion production Proton Driver Ion production ISOL target & Ion source Beam preparation ECR pulsed Ion acceleration Linac Acceleration to medium energy RCS PS High-energy part Acceleration Neutrino source 6 He: 18 Ne:   = 100 = 100 SPS Neutrino Source Decay Ring m  

e

   m  

e

m  

e

   m  

e

Oscillation signatures

•

Golden channel at a NuFact: “wrong-sign” muons

50% 50%  

e

m  m 

e

 m

detector

m     

e

     m      

Large Magnetic Detector

beam B=1 T 

e



40KT

 m 20 m 20 m iron (4 cm) + scintillators (1cm) •

wrong sign muon

Silver channel: tau appearance



e

Emulsion (4 kton) Plastic base

  

1 mm Liquid Argon (100 kton) (kinematic selection

  )   Pb

Emulsion layers

Near Detector

•

Near detector: control flux, systematics, maeasure cross sections, charm backgrounds for oscillation signals, ….

 m

CC event

•

Use silicon detectors for vertex (prototype in NOMAD)

•

10 9



interactions per year in 50 kg!!!

•

Monolithic Active Pixel (MAPS): fully active neutrino target

Physics reach neutrino factory

•

Sensitivity to

d

-

q

13 : best for neutrino factory (except at high

q

13 , in which matter effects dominate).

P. Huber et al.

High-

 b

beam not included

Performance comparable to Nufact (Burget et al.) First oscillation maximum only

Introduction to 3D detectors

• Co-axial detector – Arrayed together • Micron scale – USE Latest MEM techniques • Pixel device – Readout each p+ column • Strip device – Connect columns together

Proposed by S.Parker NIMA 395 pp. 328-343(1997).

SiO 2 +ve -ve

Operation

-ve +ve p + -ve -ve

h + h +

Bulk n

e e W 2D

E W 3D E

Carriers swept horizontally

n +

Equal detectors thickness W 2D >>W 3D Travers short distance between electrodes

+ve

Carriers drift total thickness of material • Low full depletion bias • Low collection distances  • Fast High CCE

Two methods to form pores

DRIE

• So far, maximum aspect ratio: 18:1 (depth 183 μm) • Modification to standard equipment to obtain deep narrow parallel walled pores • In conjunction with STS • • •

Electro-chemical etching

maximum aspect ratio: 30:1 (depth 440 μm,  =14 μm) 24 hours per wafer Cheap

Results - IV of devices

• Good rectifying np junction formed • • Oxide as diffusing barrier isolates individual cells RIE removal of top surface caused increase in current after -10V Glasgow 3D detector

Results - Proton irradiation

High res n-type silicon, 85 m m pitch, close-packed hexagonal pixels Irradiation with 24 GeV/c protons at CERN 7 fluences from 5 x 10 12 to 4.5 x 10 14 24GeV/c p /cm 2 For 4.5 x 10 14 (2.7 x 10 14 24GeV/c p/cm 1MeV n/cm 2 ) 2 2 years Velo inner radius Depletion voltage = 19V Type inversion observed

3D-stc detectors proposed at ITC-irst

[2]

For fab simplification

n + electrodes n + electrodes p-type substrate 50

m

m 0 V -5 V electrons are swept away by the transversal field potential distribution vertical cross-section between two electrodes

-

-8 V holes drift in the central region and diffuse towards p + contact Uniform p + layer -20 V ionizing particle Recently, Semi-3D radiation detectors with p+ columns in n-type substrates were proposed by Er änen et al. [3] [2] C. Piemonte, M. Boscardin, G.-F. Dalla Betta, S. Ronchin, N. Zorzi, Nucl. Instr. Meth. Phys. Res. A 541 (2005) 441 [3] S. Eränen, T. Virolainen, I. Luusua, J. Kalliopuska, K.Kurvinen, M. Eräluoto, J. Härkönen, K. Leinonen, M. Palviainen and M. Koski, 2004 IEEE Nuclear Science Symposium, Conference Record, paper N28-3, Rome (Italy), October 16-22, 2004

Mask Layout-Test structures

Standard (planar) test structures

3D-Diode

Pitch 80 µm 10x10 matrix Ø hole 10 µm 44 holes GR p-stop 20 µm Ø implant 44 µm

Backplane full-depletion-voltage

Preliminary

“3d-diode”/back capacitance measurements 12 10 Lateral depletion contribution to measured capacitance at low voltages Linear 1/C 2 vs V region corresponding to the same doping level of planar diodes 8 6 4 2 0 0 10 D4_4 C-V 20 30 Vrev [V] 40 50 Saturation capacitance corresponding to a depleted width of ~ 150µm)  Column depth ~ 150µm 60 2.50

2.00

1.50

1.00

1/C 2 -V 0.50

0.00

0 10 20 30

Vrev [V]

40 50 60 ~ 40V full depletion voltage (300 µm wafer)

S/N for HEPAPS2

Test beam at HERA

FAPS: RAL group

• •

FAPS could be extended to a full 20 samples per train, stored in pixel If this doesn’t fit with 0.25

m

m CMOS, will surely be OK with 0.13

m

m

• •

Idea is to relax the requirement for fast, precise, signal transmission to chip periphery during train, and so render long columns feasible, with all processing logic outside the detector active volume, as for the CCD architecture Test devices implemented using a 0.25

m

m process – TSMC(imaging)

13um hit resolution

FAPS resolution