Silicon Detectors @ the LHC ICHEP02 Chris Parkes ALICE 0.3 + 1.3 + 2.9 m2 Pixels+Drift+Strips LHCb 0.3 + 12.2 m2 Strixels! + Strips (+pixels in RICH) ATLAS 2.2 + 61 m2 Pixels + Strips CMS 0.8 + 206 m2 TOTAL = 287 m2 = 3.6 secs/m2 LHC Si Detectors ICHEP 24th -31st July 2002
Then pick a few examples…. Contents Layouts x 4 Then pick a few examples…. Sensor Designs ALICE Si Drift Detector, LHCb VELO CMS Strip Optimisation FE Electronics / Mechanics / Cooling ATLAS Pixels Module Assembly CMS Strips Q/A ATLAS Strips LHC Si Detectors ICHEP 24th -31st July 2002
ALICE Silicon Double-sided Silicon Strips Silicon Drift Detectors 2.7M 95 m pitch stereo twist p+/n+ on n strips, analogue rad-tol 0.25 m CMOS readout, 1770 modules Silicon Drift Detectors 260 modules, 0.13M channels p+/n+ on n – see later Silicon Pixel Detectors 9.8M 50 x 425 m p+ on n pixels 240 modules Occupancy 90 cm-2 R=39-43cm R=15-24cm R=4-7cm 28 cm 102 cm 3 x 2 layers LHC Si Detectors ICHEP 24th -31st July 2002
Analogue DSM/DMILL readout Tracker 4 all Si layers + Strips close to beam, outside straw drift tubes 200m pitch p+on n , stereo twist, 16 layers, 2300 sensors, 0.5M strips Vertex Locator n+ on n, 0.2M strips 8mm from beam, weird layout!!! see later Forward geometry 1m Analogue DSM/DMILL readout LHC Si Detectors ICHEP 24th -31st July 2002
ATLAS Inner Detector ICHEP Abstract 158 Pixels n+ on n, 50x400 m2 3 layers, 8 disks, 1500 modules r = 4.8 - 16 cm, 140 M channels, SemiConductor Tracker (SCT) 19,300 single sided 80 m pitch p-on-n strip detectors 6 sensor geometries Dmill BiCMOS Binary readout r = 27 - 52 cm, 6.3 M channels Tracking and Vertex reconstruction Axial magnetic field 2T Enclosed in a thermal envelope inside the solenoid, -70C 7 m 2.3 m 4 Barrel cylinders (square), 2 x 9 End-cap disks (wedge) LHC Si Detectors ICHEP 24th -31st July 2002
Two key differences of ATLAS/CMS strips Size: 4,000 15,000 modules Strip readout: Analogue DSM chip - APV Outer Barrel –TOB- Inner Barrel –TIB- End cap –TEC- Pixel Inner Disks –TID- 5.4 m 2,4 m 2 Pixel Layers R=4cm layer to be replaced by R=11cm after low lumi. Period Due to radiation damage ATLAS 5x more pixels Layout o the Tracker and sub-detectors – dimensions – running temperature 10 barrel layers, 3 inner disks, 9 outer LHC Si Detectors ICHEP 24th -31st July 2002
Design R/Phi Sensors 40-100um pitch 2nd metal readout 4um resolution Primary/ b decay Vertex reconstruction Stand alone Tracking Second Level Trigger Fast tracking Extreme Radiation Environment 8mm from beam, 1014 1 MeV n/cm2 / year One set of half disks In vacuum Retract each fill Align each fill LHC Si Detectors ICHEP 24th -31st July 2002
Opposite polarity signal observation at 40MHz n+/p+ – on –n Comparison Test-Beam Results ICHEP Abstract 181 blah Opposite polarity signal observation at 40MHz n+/p+ – on –n Comparison 200m read-out, floating strips 16 strips , 3mm !!! Bi-polar n-on-n fully efficient when 60% depleted LHC Si Detectors ICHEP 24th -31st July 2002
Built-in voltage dividers Drift Si Drift Detector segmented 2 x 256 anodes High particle multiplicity But low event rate Trade Speed for 2D Readout Rad. Tol. DSM ASIC 10-bit ADC 40 MHz sampling 4.5s drift time Temp. sensitive Control to 0.1oC Monitor with implanted MOS charge injection Drift 35mm Built-in voltage dividers R e- n n+ p+ Collect e- Constant E field LHC Si Detectors ICHEP 24th -31st July 2002
Anodic resolution, z (mm) Drift Distortions x = XSDD-Xtelescope Residual doping inhomogeneity causes charge clusters to deviate from their ideal trajectory x>0 y>0 x<0 y<0 - NTD better than FZ Si Uncorrected Anodic resolution, z (mm) Corrected 25(z)/33(r) m LHC Si Detectors ICHEP 24th -31st July 2002
Also capacitance work: w/p ratios, <100> crystal orientation…. CMS Strip Design Width of the metal strip extending beyond implants to guarantee good HV stability and avoid high field regions at implant edges with without Also capacitance work: w/p ratios, <100> crystal orientation…. LHC Si Detectors ICHEP 24th -31st July 2002
ATLAS Pixels- Readout Rad-hard DSM chip success Electronics 8 Assemblies, bump-bonded, Irradiated 1015 1 MeV n/eq. 13m resolution 98% efficiency 350e- noise Some final tweaking (e.g. high SEU rate) Final iteration end 2002 Then production…. Electronics Bump Bonding (In/SnPb) Typical wafer map new run Yield 85 % (register tests) Sensors LHC Si Detectors ICHEP 24th -31st July 2002
ATLAS Pixel – Insertable Layout allows independent installation & removal of pixels decouples ID / pixel schedule facilitates upgrades (e.g. replace R=4cm B layer) 7m Pixel Detector Service and Beampipe Support Insertable pixel here Mechanic/Cooling integrated Position stability ~10m Remove 15KW (FE chips) Keep at –6oC Glassy carbon Tube between CC facings LHC Si Detectors ICHEP 24th -31st July 2002
The module assembly is fully automatic!!!!! 9,648,128 strips, 75,376 APV chips, 15,232 modules …. The module assembly is fully automatic!!!!! ICHEP Abstract 181 Glue dispensing syringe Sensor pick up tool Tool rack Silicon sensors Hybrid pick up tool Assembly platform Carbon fibre frames Vacuum system Hybrids Developed at CERN and exported to the 7 laboratories that assemble modules perugia
Readout tested with automatic system Gantry system locates automatically components for assembly by visual search for a marker Image found First 10 endcap modules Readout tested with automatic system s DX=3 mm DF s DF=1.5 mrad DX <20 mm LHC Si Detectors ICHEP 24th -31st July 2002
Quality Assurance - ATLAS Strips On ALL modules: Production Status 85% detectors delivered >99% yield Some delays in forward but module construction is underway . Metrology 100 pts per detector Leakage current IV to 500V I 24hr stability Electrical 99% strips efficient, low noise @ 1fC threshold Gain, discriminator offset Timewalk Thermal cycling -250C +400C x 10 24 hr with ASIC Clocked & Triggered Metal short Detector Manufacture 100% achieved schedule 0% 2001 2002 On subsamples: Irradiation Tests Beam Test Source Test Laser Test Implant break LHC Si Detectors ICHEP 24th -31st July 2002
LHC 287 m2 Pixels, Strips, Drift 200M diodes 22,000 modules Si for Tracking (not just vertexing) I would like to thank the silicon groups of all 4 experiments for their assistance in the preparation of this presentation Regulation Tennis Court Size 36x78 ft2 261 m2 LHC Si Detectors ICHEP 24th -31st July 2002