ATLAS silicon microstrip detector System (SCT)

Transcription

1 ATLAS silicon microstrip detector System (SCT) Barrel modules Y. Unno, KEK For SCT collaboration Endcap modules SCT

2 ATLAS detector Diameter Barrel toroid length Endcap end-wall chamber span Overall weight 25 m 26 m 46 m 7000 Tons

3 Installation schedule v. 6.0 The construction and installation planning, as presented to the recent LHCC Installation Review, foresees to have the initial staged detector ready at the end of 2006 Name Duration Start Finish UX 15 Hand-over 0 days 14 Apr '03 14 Apr '03 PHASE 1: Infrastructure 377 days 14 Apr '03 24 Sep '04 UX available for ATLAS 0 days 21 Nov '03 21 Nov '03 PHASE 2: Barrel Toroid & Barrel Calorimeter 466 days 21 Nov '03 16 Sep '05 Phase 2a: Bedplates & Feet 20 days 21 Nov '03 19 Dec '03 Phase 2b: Barrel Toroid 309 days 12 Dec '03 1 Mar '05 Phase 2c: Barrel Calorimeter 354 days 3 May '04 16 Sep '05 Phase 2d: Racks, Pipes & Cables 273 days 24 Nov '03 13 Dec '04 PHASE 3: End-cap Calorimeters & Muon Barrel 408 days 7 Sep '04 10 Apr '06 Phase 3a: Pipes & Cables 205 days 7 Sep '04 28 Jun '05 Phase 3b: Endcap Calorimeter C 245 days 22 Oct '04 7 Oct '05 Phase 3c: Muon Barrel 155 days 14 Dec '04 26 Jul '05 Phase 3d: Endcap Calorimeter A 237 days 12 May '05 10 Apr '06 PHASE 4: Big Wheels & Inner Detector 234 days 11 Jul '05 2 Jun '06 Phase 4a: Big Wheels 161 days 11 Jul '05 21 Feb '06 Phase 4b: Inner Detector 191 days 8 Sep '05 2 Jun '06 PHASE 5: End-Cap Toroid & Small Wheels 166 days 22 Nov '05 12 Jul '06 Phase 5a: Endcap Toroid 166 days 22 Nov '05 12 Jul '06 Phase 5b: Small Wheels 56 days 12 Apr '06 28 Jun '06 PHASE 6: Beam Vacuum, End wall Chambers, Shie 54 days 26 May '06 9 Aug '06 Phase 6a: Completion of the Beam Vacuum 25 days 26 May '06 29 Jun '06 Phase 6b: End wall Chambers (EO) 21 days 14 Jun '06 12 Jul '06 Phase 6c: Shielding & full Magnet test 26 days 5 Jul '06 9 Aug '06 Global Commissioning 60 days 10 Aug '06 1 Nov '06 Cosmic tests 40 days 2 Nov '06 29 Dec '06 ATLAS Ready For Beam 0 days 29 Dec '06 29 Dec ' Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 14 Apr '03 UX 15 Hand-over 377 days PHASE 1 21 Nov '03 UX available for ATLAS 466 days PHASE 2 20 days Phase 2a: Bedplates & Feet 309 days Phase 2b: Barrel Toroid 354 days Phase 2c: Barrel Calorimeter 273 days Phase 2d: Racks, Pipes & Cables 408 days PHASE days Phase 3a: Pipes & Cables 245 days Phase 3b: Endcap Calorimeter C 155 days Phase 3c: Muon Barrel 237 days Phase 3d: Endcap Calorimeter A 234 days PHASE days Phase 4a: Big Wheels 191 days Phase 4b: Inner Detector 166 days PHASE days Phase 5a: Endcap Toroid 56 days Phase 5b: Small Wheels 54 days PHASE 6 25 days Phase 6a: Completion of the B 21 days Phase 6b: End wall Chamber 26 days Phase 6c: Shielding & full M 60 days Global Commissioning 40 days Cosmic tests 29 Dec '06 ATLAS Ready For Beam

4 Central solenoid 2 Tesla magnetic field for the inner tracking volume Sharing vacuum cryostat of Liquid Argon EM calorimeter Contribution of the ATLAS-Japan by the superconducting -magnet experts of KEK Fabricated by Toshiba Completed and tested in Japan in Jan Transported to CERN in Oct. 2001

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7 Transportation of ATLAS Central Solenoid Yokohama Bay ( ) Completed and Tested at Toshiba ( ) the Rhine Port Rotterdam ( ) Basel ( ) CERN B180 ( ) Acceptance test ( )

8 Inner detector Solenoid coil Cryostat Liquid Argon EM calorimeter Inner detector volume Volume = φ2.3 m x 6.8 m Solenoid coil inside Liq. Argon cryostat 2 Tesla

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10 ATLAS Silicon Microstrip Semiconductor Tracker (SCT) Radiation fluence R(cm) TRT SCT PIXEL 0.7x10 13 TRT 1.0x x10 13 SCT 2.2x10 13 Z(cm) 1 MeV neutron equivalent, yearly fluence SCT: ~1.8x10 13 n/cm 2 / yr / L= % uncertainty in the fluence (cross section, etc.) 10 yrs operation: 3 yrs at yrs at Neutron damage ~ 1.5x Proton damage Fluence over 10 yrs: - Neutrons ~2x10 14 n/cm 2 (=1.8x10 13 x1.5x7.3) - Protons ~3x10 14 p/cm 2 (=2x10 14 x1.5)

11 Barrel: r [mm] #modules B B B B Total sensors 34.4 m2 SCT Barrel (and Endcap) Endcap: 9 discs x modules 7104 sensors 1040 mm 1500 mm

12 SCT barrel module Hybrid assembly BeO facings (far side) p-in-n singled-sided sensors back-to-back gluing Slotted washer 40 mrad stereo 1.2% Xo Silicon sensors Baseboard TPG Datum washer Connector BeO facings (cooling side)

13 Barrel module parameters Sensors : x mm 2, p-in-n, single-sided Strip directions : 20 mrad Operating temperature : - 7 C Total chip power : 6.0 W nom., 8.1 W max. Thermal runaway heat flux: > 240 mw/mm 2 at 0 C Mechanical precisions : back-to-back: < 5 mm (in-plane lateral), < 10 mm (in-plane longitudinal), < 50 mm (out-of-plane) Fixation point: < 30 mm (in-plane) Radiation length: < 1.2% X 0

14 ATLAS silicon microstrip sensors production Hamamatsu Photonics: Barrel: spares (~20%) ~ Japan + UK + Nordic Endcap: ~61% of ( spares(~20%) ~ 5200 UK + Spain CIS: Endcap: ~39% ~ 3300 Germany Production: Mar started, Nov near completion

15 Hybrid of the barrel ATLAS SCT ABCD3T chips (12 x 128 ch) glass pitch-adaptor (2 x 6 x 128 ch) connector carbon-carbon bridge (underneath) flexible Cu/PI circuit

16 BeO facing ABCD chip Air gap (0.4mm) Cu/polyimide flex Connetor Cooling block Carbon-carbon bridge TPG Si sensor Cross section of the module 1 mm 10 mm Cooling block Flow paths of heat

17 Barrel module baseboard Encapsulated VHCPG Baseboard with BeO facing plates VHCPG:(very high thermal Conductivity pyrolytic graphite) In-plane thermal conductivity: W/mK Thickness: m

18 Thermal Properties -14 C -17 C -20 C Simulated thermal profile with Q chip =6W bulk heat generation (mw/mm C)

19 ATLAS silicon micstrip sensors 6 different shapes from 4-inch wafer p-in-n, 80 µm pitch, 768 strips, AC-coupled, 285 µm thick Barrel - Square Endcap - Wedges Wedge detectors for forward 80 µm x 768 strip = 61.4 mm, 62.0 mm strip length 1 mm edge space

20 Operation bias voltage in ATLAS Non-irradiated ~ 150 V Near the end of experiment ~ 350~500 V 5 Median charge [fc] Non-irradiated Irradiated 3x10 14 p/cm 2 mod1 mod2 mod5 mod6 mod3 mod Bias voltage [V] Y. Unno et al, IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 49, NO. 4, AUGUST 2002

21 Pre-irradiation Pre-irradiation, room temp. 1 Leakage/Volume [ua/cm^3] Barrel sensor = 1.16 cm 3 ~200 na Very Good! Bias voltage [V]

22 Post irradiation Leakage/Volume [ua/cm^3] 3x10 14 p/cm 2, -18C, Current 3 orders of magnitude higher Bias voltage [V] Smooth up to 500 V! Average of irradiated sensors <B2-111> <W12> <W21> <W22> <W31> <W32> <B2-100> Little difference in shapes

23 What will happen in case... Microdischarges below 350 V Samples from rejected sensors Pre-irradiation, room temp. (Spec: no MD below 350 V) Leakage/Volume [ua/cm^3] Bias voltage [V]

24 Post irradiation of microdischarged sensors Post irradiation, -18C No visible effect Leakage/Volume [ua/cm^3] Smooth! Why? Type inversion P-N junction in the backside Little field till full-depletion in the strip side Bias voltage [V]

25 Leakage current [ua] Series module production Series barrel module production started in Feb As of Sep. 2002, ~100 modues I-V Curve at +15 C Two modules strip's pad damaged Bias voltage [V] Microdischarge 11 modules >350 V

26 preirrad, +15C, Post irradiation of microdischarge module Leakage [ua] preirrad Bias voltage [V] postirrad, -15C, Smooth up to 500 V Same as individual sensors Leakage [ua] postirrad Bias voltage [V]

27 Decay of microdischarge current Also, microdischarge currents decay out to normal currents in a few hundred minutes 500V, +15 C Leakage current [ua] #100 has very long time const Time [min.]

28 Visualization of hot spot Discharging location is hot (minutely) CCD camera with extended sensitivity to infrared, and cooled to reduce thermal noise Hot spot is visible in overlaying over visual image #100 - tiny hairline metal between the wire (GND) and sensor edge (HV)

29 Multi-module system test 12 modules in a row, Double row overlap,... Room temp. run, Cold run (with irradiated modules) Studies of noise pickups, grounding and shielding, etc Barrel system test

30 Input-noise (ENC) ATLAS SCT: 3-pt gain scans - Wed Jul 31 11:08: B186 Barrel System Test Run 991 Scans 5-7 Input-noise at 2fC from 3point gain scans Multimodule Elec. Stand Module

31 Endcap systemtest On-going...

32 Barrel sector test Final support structure, cooling pipes, refrigeration system Dummy heater modules Real modules

33 Barrel sector test Thermal imaging - visualize temperature distribution Coolant in - Blue cold pipes (Dummy) module heater on - green to yellow Sector carbon-fibre cylinder - room temp. red

34 Barrel support cylinder in production Carbon skin - Carbon honycomb core 1st cylinder (B3) delivered Still long way to attach brackets, cooling pipes, opto-powerharnesses

35 Summary ATLAS is targetting the completion of the detector in the end of 2006, expecting the first beam collision in Feb Central solenoid was completed and is in preparation for installation at CERN Series production of SCT silicon microstrip sensors of ~18000 are near completion Sensors show good performance in pre- and post-irradiation, and even in the case of microdischarge as low as 250V there is no visible effect after irradiation. Together with the decay of the microdischarge current, the sensors are robust for high voltage operation Series production of SCT barrel modules has started. 1st support cylinder (B3) has been delivered System tests are progressing. No show-stopper, yet Lots of details lie ahead toward the installation of SCT in early 2005