gridpix/gossip for atlas sct upgrade ilc clic …….insulators in strong e- fields………....
TRANSCRIPT
GridPix/Gossip for
ATLAS SCT UpgradeILCCLIC
…….insulators in strong E- fields……….…….the frustration of innovation………..
Harry van der GraafNikhef, Amsterdam
IEEE-NSS ConferenceMPGD-Si Detector WorkshopDresden, Oct 18, 2008
Micro Strip Gas Counters: hard to operate:
- discharges, ruining electrodes- ageing
! Very strong electric field in insulator’s volume & surface !
GEMs:
- often cascade of 3 GEMs used to limit gain per GEM to ~40- ‘rim’ (dia hole Cu/kapton) critical- shape of hole wall critical- charge up effects
Atsuhiko OCHIAtsuhiko OCHIKobe University, JAPANKobe University, JAPAN
13 Oct. 2008 2nd RD51 workshop in Paris
GEM ProductionGEM Production
x750
100um
80um
Remove copper by wet etching
Irradiate CO2 laser
Remove remaining edge from the other side
RIKEN/SciEnergy GEM(thick-foil and fine-pitch) pitch 80um hole 40um thickness 100um
Recent Status of Development
GEM test setup and parameters– Thick-foil and fine-pitch GEM
(single layer)– HV supplied through a resister
chain– Ed=2.5kV/cm, Ei=4~5kV/cm,
V⊿ GEM=300~600V
– Gas: Ar+CO2(30%) flow
– Readout by 1cm x 1cm pad
Gain measurement– Gain vs applied voltage
– X-ray from Fe-55 (5.9keV)
Gain Curve (RIKEN GEM)Gain Curve (RIKEN GEM)
Fe-55 spectrum5.9keV
gain=3x104
To keep good spatial resolution and keep discharge point at high gain.Our GEM is most suitable for Cosmic X-ray Polarimeters.
Recent Status of Development
Gain instability (RIKEN GEM)Gain instability (RIKEN GEM)
F. Simon (IEEE, 2006)T. Tamagawa(IEEE,2007)
time (s)
rela
tive
gain
3 hours
No gain increase in short measurementsThis is not for a special batch of GEMs but for all GEMs we producedPossible reasons;
Less charging-up due to cylindrical hole shapeLess polarization of Liquid Crystal Polymer
No increase and decrease just after HV on.
Recent Status of Development
GemGrid 1
GemGrid 2
Bulk high-resistivity materials
hydregenated amorphous silicon
allowed gains up to 5 105
staying proportional!
Si-rich silicon nitride (Si3N4)
Measurements on Si-rich Silicon Nitride (Si3N4)
Column resistance: ρ D/OPotential surface measurable: gain drop factor 2 at dV = 17.5 VWith known current: bulk resistivity ρ measurable: ~ 1 – 50 1013 Ohm cm
Surface time constant: Column resistance x (virtual colum capacitance) =
(ρ D/O)*(ε O/D) = ρ ε (independant of layer thickness D!)
Resistive Plate Chambers (RPCs)
-essential: high-resistivity material- quenches sparks- sufficient charge compensation current
Traditional: insulator + dope (Sardinian oils…?)New: high-resistivity bulk (ceramic) material: higher counting ratesCompare graphite covered mylar foil
Micromegas on pillars
Edge discharge protection foil
discharges + vibrations
conductivity of kapton
Charge-up effects
After (rapid) ramping of HV:
- polarisation: reduction of E-field in insulator (bulk) volumeIn homogeneous field with insulator // to field: nothing
With E component perp. on insulating surface: modificationof potential by hitting e- and/or ions until E // surface
GEM hole
region ofworse insulation
equalizing with water
Stronger effects forgood insulator
Very preliminary:
Use as little as possible insulating surfaces // strong E fieldsApply high-resistivity materials instead of insulators
Even more preliminary:
As for gain: GEMs perform les than (corresponding) Micromegas
April 2004 Micromegas + MediPix 2 NIKHEF/Saclay/Univ. Twente:
MediPix2 pixel sensorBrass spacer blockPrinted circuit boardAluminum base plate
Micromegas
Cathode (drift) plane
55Fe
Baseplate
Drift space: 15 mm
MIPs
No source, 1sNo source, 1s5555Fe, 1sFe, 1s
He/Isobutane80/20Modified MediPix
δ-ray!14 mm
Integrate Micromegas and pixel sensor:
InGrid
‘wafer post processing’by
Univ. of Twente, MESA+’
Full post-processing of a TimePixFull post-processing of a TimePix• Timepix chip + SiProt + Ingrid:
“Uniform”
MESA+
IMT Neuchatel
Charge mode
14 mm
A “long” cosmic track
Timepix +
20 μm thick Siprot
+
Ingrid
Drifttime (bin = 10 ns)
Stable operation in He iC4H10
10 mm
cathode @ - 1500 V 14 mm
Si (vertex) track detector GOSSIP
CMOS chip
Si depletion layer
Vbias
• Si strip detectors• Si pixel detectors• MAPs
Gas: 1 mm as detection medium99 % chance to have at least 1 e-
Gas amplification ~ 1000:
Single electron sensitive
All signals arrive within 16 ns
Cluster3
Cathode (drift) plane
Integrated Grid (InGrid)
Cluster2
Cluster1
Slimmed Silicon Readout chipInput pixel
1mm,100V
50um, 400V
50um
Gossip: replacement of Si tracker
Essential: thin gas layer (1.2 mm)
1.2 mm
GOSSIP-Brico: PSI-46 (CMS Pixel FE chip)First prototype of GOSSIP on a PSI46 is working:
• 1.2 mm drift gap• Grid signal used as trigger• 30 µm layer of SiProt
Tracking sensor material: gas versus Si- it is light
- primary electrons can simply be multiplied: gas amplification: low power
- no bias current: low power & simple FE circuits
- gas can be exchanged: no radiation damage of sensor
- gas has a low εr: with small voxels the source capacity can be small (10 fF) allowing fast, low-noise, and low-power preamps
- gas is usually cheap
- low sensitive for neutron and X-ray background
- δ-rays can be recognized
- [high ion & electron mobility: fast signals, high count rates are possible]
- discharges/sparks: readout system should be spark proof- ageing: must be solved and must be understood / under control- diffusion: limits max. drift length
CMOS Chip protection against - discharges- sparks- HV breakdowns- too large signals
Emperical method:Try RPC technology
Amorph Si (segmented)
Silicon Protection: SiProt
Qmax ~ 1 – 2 fC
Chip may die if Qmax > 10 fC
Ageing
Radiation damage of CMOS pixel chip is relevant- common for all tracking detectors- believed to widthstand ATLAS Upgrade Dose in 90 nm technology
Radiation damage of sensor: not relevant for Gossip sensor since this is gas being exchanged
Typical for gaseous detectors: the deposit of an (insulating) polymeron the electrodes of a detector. Decrease of signal amplitude
Little ageing expected:- little primary ionisation (~ 10 e-/track)- low gas gain (500 – 1000)- large anode surface (compare pixel anode plane with surface of thin wire)- E-field at flat anode ~3 lower than E-field at anode wire
Linear fitI = I0 + a.ta = -0.5932=> a/I2 = 0.0183
av current = 5.9 A=> total charge deposited = 5.9*3600*24*4 = 2.55 Csurface 0.49 cm2
=> 5.2 C/cm2
assume: drift distance 1 mm Ar/CH4 having 9e-/mm=> 1 mip = 9*1000*1.6*10-19
= 1.44 10-15Cdeposited charge corresponds to3.6 1015 mips/cm2
X ray irradiation at PANalytical (detail)
Time
14-M
ay-0
5
16-M
ay-0
5
18-M
ay-0
5
I cath
(A
)
0
2
4
6
8
Icath
1/x fit
3.6x1015 mips/cm2@ gain = 1000
gas: standard Ar/Methane 90/10. Deposit containing C found on anode
Irradiation with 8 keV X-rays:Irradiation with 8 keV X-rays:
No No rate effectsrate effects up to anode up to anode current density of 0.2 current density of 0.2 μA / mm / mm22
very fast track counting very fast track counting possible!possible!
After 0.3 Coulomb/mm2:
(eq. 3.7 x 1016 MIPs/cm2 !!)
deposit of carbon polymer on anode is clearly visible. Micromegas is clean (!?)Little deposit on cathode, and……Chamber still worked!
Ageing
Construction of many test chambersprototypesNext-1,2,3,4,5Next QuadNext-64 (ReNexed, ReLaXd)DICEAgeing Chambers
Next-64 / ReLaXd / ReNexd
CO2 cooling!
DICE
DICE
Nuclear ReactorWater Bassin10 x 10 x 10 m3
ReactorInstituteDelftRID
Upgraded SCT: Gossip could replace:
- Pixel vertex detector: Gossip- Si Strip detectors: replace by Gossip Strixel detectors- TRT: use Gossip as tracker/TR X-ray detector
Essentials:
- power dissipation: 60 mW/cm2
- intrinsic mass: 0.1 % radiation length- low cost: 10 $ / cm2
Barrel SCT unit
EndCap SCT unit
Semiconductor (pixel, strip) Semiconductor (pixel, strip) detectorsdetectors
Depleted Si, 300 μm
(pixel) chip withpreamps, shapers,discriminators
Vbias = 150 V
electron-holepairs
ATLAS pixel: basic elementATLAS pixel: basic element
C-C support
sensor
Flex Hybrid
bumps
MCC Side view
not to scale
Wire-bonding FE’sWire-bonding MCC
FE chipFE chip
Flex module 2.xFlex module 2.x
- Ladder strings fixed to end cones- Integration of beam pipe, end cones & pixel vertex detector- 5 double layers seems feasible
Gossip in ATLAS (Goat-1) Stave TimePix-2 chipSiNProt layerInGrid (Si3N4)Gas Cover
‘G’(round)String
‘P’(ositive)Stringcarrying 1.3 V
‘Road’: C-fibre reinforced databus + aux services
Stiff, light Stave formed by G-stringP-stringRoad triangle
StainlessSteel tubefor CO2 cooling
casted aluminiumpower line
gasmanifold
Ø60mm Beampipe
Inner Layer: 7 double Goat strings
CO2 cooling channels
P-string conductor (+voltage)
G-string conductor (+voltage)
Gossip detector unit
Gossip readout
GOAT: GOssip in ATlas
Upgraded SCT: Gossip/GridPix could replace:
- Pixel vertex detector: Gossip- Si Strip detectors: replace by Gossip Strixel detectors- TRT: use GridPix as tracker/TR X-ray detector
strixels/strips
preamp channels
Essentials:
- power dissipation: 1/16 x 60 mW/cm2 = 4 mW/cm2
now:25 mW/cm2
- intrinsic mass: 0.1 % radiation length- low cost: 10 $ / cm2
~ 20 mm
Upgraded Tracker: Gossip could replace:
- Pixel vertex detector: Gossip- Si Strip detectors: replace by Gossip Strixel detectors- TRT: use Gossip with 17 mm Xe layer
as tracker/TR X-ray detector
Essential:- high position-resolution tracker throughout tracker- low mass, low cost detector- Efficient TRD possible
L=30 mm
0.05 mm
V0 V1
Anatoli Romaniouk, Serguei Morozov, Serguei KonovalovMartin Fransen, Fred Hartjes, Max Chefdeville, Victor Blanco Carballo
Transition Radiator
Testbeam Nov 5 – 12, 2007PS/T9: electrons and pions, 1 – 15 GeV/c
Samples pions (left) and electrons (right)
Particle Identification Particle Identification
6 GeV/c
5 (double) layer Gossip Pixel
4 layer Gossip Strixel
3 layers Gossip TRT
radiator
Gas instead of SiPro:- no radiation damage in sensor: gas is exchanged- modest pixel (analog) input circuitry: low power, little space- no bias current: simple input circuit- CMOS pixel chip main task: data storage & communication (rad hard)- low detector material budget: 0.06 % radiation length/layer
typical: Si foil. New mechanical concepts- low power dissipation : little FE power (2 μW/pixel); no bias dissipation- operates at room temperature (but other temperatures are OK)- less sensitive for neutron and X-ray background- 3D track info per layer if drift time is measured
Con:- Gaseous chamber: discharges (sparks): destroy CMOS chip- gas-filled proportional chamber: ‘chamber ageing’- Needs gas flow- Parallax error: 1 ns drift time measurement may be required
New mechanics + cooling concepts for Gossip
- As little as possible material- detector consists of foil!- less power required ( less cooling) w.r.t. Si
string: power, chip support, cooling
in 2030….
‘balloon’
‘laundry line’
Minimum Material Budget(% rad length)
Z = 0 mm Z = +/-600 mm
Gossip detector (50 μm Si) 0.06 0.06
Cooling (stainless steel tube) 0.001 0.001
Power (max 0.28 mm aluminium) 0.0 0.3
Data transfer (max 1.7 mm kapton)0.0 0.6
total 0.06 1
angle correction x √2 0.09 x 2 x √2 3
- Ladder strings fixed to end cones- Integration of beam pipe, end cones & pixel vertex detector- 5 double layers seems feasible
Virtual goal: ATLAS pixel vertex
Gossip in ATLAS (Goat-1) Stave TimePix-2 chipSiNProt layerInGrid (Si3N4)Gas Cover
‘G’(round)String
‘P’(ositive)Stringcarrying 1.3 V
‘Road’: C-fibre reinforced databus + aux services
Stiff, light Stave formed by G-stringP-stringRoad triangle
StainlessSteel tubefor CO2 cooling
casted aluminiumpower line
gasmanifold
Ø60mm Beampipe
Inner Layer: 7 double Goat strings
CO2 cooling channels
P-string conductor (+voltage)
G-string conductor (+voltage)
Gossip detector unit
Gossip readout
GOAT: GOssip in ATlas
The future:
Electron Emission Foil
MEMS made MicroChannelPlates: 200 ps time resolution: CLIC
electron emission foil
CMOS pixel chip
electron avalanche in gasEE-Foil replaces InGridParallel Plate Chamber
electron emission foil
CMOS pixel chip
replace gas by vacuumMicro Channel Platesub-ns time resolutionNote CLIC experiments
July 2005: ATLAS Upgrade Worlshop GenuaContribution Gossip was refused:
……………..pixel B-layer replacement too soon for new R&D projects…..
Sept 2006: ATLAS Upgrade Workshop Liverpool:Contribution Gossip was granted (after repeated requests)
Dec 2007: ATLAS Upgrade Workshop Valencia:Invited to present Gossip R&D project
Sept 2008: PSD8, Glasgow:keynote: Norbert Wermes: Pixel detectors for charges particlesmentions 3D, Diamond, MAPs, but NOT Gossip
Si tracking detectors
- the ultimate detector in HEP- associated with Moore’s Law, chip technology
Proposal:
(imaginary) separation of
Interaction Matter and
readout electronics
Integration (MAPs) maybe profitable later
Si (vertex) track detector GOSSIP
CMOS chip
Si depletion layer
Vbias
• Si strip detectors• Si pixel detectors• MAPs
Gas: 1 mm as detection medium99 % chance to have at least 1 e-
Gas amplification ~ 1000:
Single electron sensitive
All signals arrive within 16 ns
Cluster3
Cathode (drift) plane
Integrated Grid (InGrid)
Cluster2
Cluster1
Slimmed Silicon Readout chipInput pixel
1mm,100V
50um, 400V
50um
NIKHEFNIKHEFHarry van der Graaf, Max Chefdeville, Fred Hartjes, Jan Timmermans, Harry van der Graaf, Max Chefdeville, Fred Hartjes, Jan Timmermans, Jan Visschers, Marten Bosma, Martin Fransen, Yevgen Bilevych,Jan Visschers, Marten Bosma, Martin Fransen, Yevgen Bilevych,Wim Gotink, Joop RovekampWim Gotink, Joop Rovekamp
University of TwenteUniversity of TwenteCora Salm, Joost Melai, Jurriaan Schmitz, Sander Smits,Cora Salm, Joost Melai, Jurriaan Schmitz, Sander Smits,Victor Blanco CarballoVictor Blanco Carballo
University of NijmegenUniversity of Nijmegen Michael Rogers, Thei Wijnen, Adriaan Konig, Jan Dijkema,Michael Rogers, Thei Wijnen, Adriaan Konig, Jan Dijkema,
Nicolo de GrootNicolo de Groot
CEA/DAPNIA SaclayCEA/DAPNIA SaclayD. Attié, P. Colas, I. GiomatarisD. Attié, P. Colas, I. Giomataris
CERNCERNM. Campbell, X. LlopartM. Campbell, X. Llopart
University of Neuchatel/MTIUniversity of Neuchatel/MTINicolas WyrschNicolas Wyrsch
Czech Tech. Univ. Prague, PrahaCzech Tech. Univ. Prague, PrahaPixelman: T. Holy et al.Pixelman: T. Holy et al.