1. ATLAS SemiConductor Tracker Detector Module Design and Performance — Towards Production of Detector Components Lars Eklund for the ATLAS/SCT Collaboration

2. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University ATLAS General LHC (Large Hadron Collider) A Toroidal LHC ApparatuS p-p collisions at 14 TeV CM Energy A General Purpose LHC experiment Design luminosity 10 34 cm -2 s -1 Data taking from 2006

3. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University ATLAS Inner Detector Pixel Detector (Silicon pixel detector) 3 layers, 8 disks r = 4.8 - 16 cm, 140 M channels SemiConductor Tracker (SCT) (Silicon strip detector) r = 27 - 52 cm, 6.3 M channels Transition Radiation Tracker (TRT) (Straw tube detector) r = 56 - 107 cm, 330 k channels Tracking and Vertex reconstruction Axial magnetic field 2T Enclosed in a thermal envelope inside the solenoid 7 m 2.3 m

4. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University SCT General Layout: 4 Barrel cylinders, 2 x 9 End-cap disks 4088 Silicon modules (2112 Barrel and 1976 Forward (four different kinds)) 61 m 2 silicon, 6.2 M channels Coverage: pseudorapidity |  | < 2.5 (|  | < 1.4 for Barrels & 1.4 < |  | < 2.5 for End-caps providing 4 space points per track Resolution Barrel:  (R  ) = 16  mForward:  (R  ) = 16  m  (z) = 580  m  (R) = 580  m (From Technical Design Report, confirmed by Test Beams 5.6 m 1.53 m 1.04 m End-cap A End-cap C Barrel

5. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University SCT Environment Radiation Environment: Maximum values for SCT Maximum values for SCT Corresponding to 10 years of running @ LHC Corresponding to 10 years of running @ LHC 10 MRad Ionising dose 10 MRad Ionising dose 2 * 10 14 n/cm 2 1 MeV NIEL equivalent 2 * 10 14 n/cm 2 1 MeV NIEL equivalent Thermal Environment: Avoid reverse annealing of silicon detectors Avoid reverse annealing of silicon detectors Limit leakage current in damaged silicon detectors Limit leakage current in damaged silicon detectors ASICs power ~ 7 W per module ASICs power ~ 7 W per module Operating at T DET  -7 ºC Operating at T DET  -7 ºC ATLAS event seen in the Inner Detector Requirements: 40 MHz Bunch-crossing frequency 40 MHz Bunch-crossing frequency 3  s trigger latency, 1 % occupancy 3  s trigger latency, 1 % occupancy 100 kHz Level 1 Trigger frequency 100 kHz Level 1 Trigger frequency Magnetic field 2T Magnetic field 2T Low material < 0.4 X 0 Low material < 0.4 X 0 No alignment needed within the detector module No alignment needed within the detector module Hit efficiency 98%, noise occupancy < 5*10 -4 Hit efficiency 98%, noise occupancy < 5*10 -4

6. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University The SCT Module 936 Outer Forward Modules 640 Middle Forward Modules (including 80 short middle modules, excluding the far detectors) 2112 Barrel Modules 400 Inner Forward Modules Difference Barrel/Forward detector modules:  Mainly geometry, some design choices give some conceptual differences. Difference between different Forward detector modules:  Geometry Details in my presentation are from Barrel modules.

7. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University SCT Module — Pictures Forward Middle detector module Barrel detector module

8. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University SCT Module — Composition Exploded picture of a Barrel Module. Design slightly modified Kapton Hybrid TPG Baseboard with BeO facings Silicon Detectors Front-end ASICs Silicon detectors: Four single-sided detectors Four single-sided detectors Mounted back to back with 40 mrad angle Mounted back to back with 40 mrad angle Base boards: TPG (Thermo Pyrolitic Graphite) TPG (Thermo Pyrolitic Graphite) Encapsulated with 20  m epoxy Encapsulated with 20  m epoxy Facings to cooling blocks of BeO Facings to cooling blocks of BeO Kapton Hybrids Kapton printed circuit flex Kapton printed circuit flex C-C bridge: C-C bridge: mechanical stability mechanical stability good thermal conductivity good thermal conductivity provides a gap between hybrid and detectors provides a gap between hybrid and detectorsASICs: BiCMOS process BiCMOS process Binary read-out Binary read-out

9. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Detectors Hamamatsu Barrel Detector Single Sided, used back-to-back p+ strips in n bulk silicon 768 strips Barrel: 80  m pitch, 60 mm strips Forward: ~50-90  m pitch, ~55-65 mm strips AC coupled Backside metal bias contact Thickness 285  m (260  m Forward Inner) Leakage current – – Pre-irrad: < 6  A @ 150 V & 20 ºC – – Post-irrad: < 250  A @ 350 V & -18 ºC Deposited charge from a m.i.p. : 3.6 fC ( 22 500 e)

10. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Front-end ASICs ATMEL DMILL BiCMOS process ATMEL DMILL BiCMOS process (Digital CMOS, Analogue Bipolar) Radiation Hard technology Radiation Hard technology Binary read-out Binary read-out Optical links for CLK/COM and data. Optical links for CLK/COM and data. ~ 20 ns shaping time ~ 20 ns shaping time 128 Channels Bipolar front-end: Preamplifier, Shaper & Discriminator 132 cells pipeline  3.3  s latency for Level 1 Trigger Read-out buffer Data compression logic Built-in calibration circuitry for charge injection Control circuitry Double set of LVDS drivers/receivers for: Clock, Commands, data & inter-chip communication Noise ~1400 ENC Noise ~1400 ENC Gain ~ 55-60 mV/fC Gain ~ 55-60 mV/fC Noise Occupancy < 5*10 -4 Noise Occupancy < 5*10 -4 (@ 1 fC Threshold)

11. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Thermal/Mechanical Performance Thermal Performance: Cooling block - 14 ºC Cooling block - 14 ºC Detectors -10 ºC Detectors -10 ºC Hottest chip 6 ºC Hottest chip 6 ºC Z-profile of a Barrel Detector Module: — Bow intrinsic to the silicon sensors. X and Y: Back to front alignment crucial. Thermal simulation of a Barrel ModuleZ profile of a prototype module built in at Oslo University

12. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Radiation Tolerance Extensive Program has been performed to assure Radiation Hardness: Silicon sensors: Irradiation program during several years. Silicon sensors: Irradiation program during several years. – Permanent set-up at CERN PS, to reach full ATLAS/SCT dose in 1-2 weeks (3*10 14 p/cm 2 ) – Annealing + measurements of depletion voltage, leakage current, S/N, strip defects … – Irradiation on batch level during production as a part of the QA procedures. – X-checks with irradiation elsewhere. Optical read out links. Separate program to assure radiation hardness. Optical read out links. Separate program to assure radiation hardness. ASICs: Driving force behind the final design work of the ASICs ASICs: Driving force behind the final design work of the ASICs – Irradiation of single chips, hybrids and complete detector modules including silicon sensors. – ATLAS/SCT equivalencies:3*10 14 p/cm 2 @ CERN, Geneva 2*10 14 n/cm 2 @ IJS, Ljubljana 2*10 14 n/cm 2 @ IJS, Ljubljana 2*10 14  /cm 2 @ PSI, Villingen 2*10 14  /cm 2 @ PSI, Villingen 10 MRad x-ray @ CERN, Geneva Low dose-rate studies @ LBL, California

13. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Radiation Tolerance (2) Irradiation of ASICs (continued): Irradiation of ASICs (continued): –Characterisation before, during and after the irradiation. – Digital functionality, parameterisation of the analogue front end (gain, noise, matching …) – Power consumption (Especially digital current consumption) – Single Event Upset Measurements (SEU) – During production: Irradiation on wafer level with x-rays (CERN, Geneva) Irradiation on batch level with neutrons (IJS, Ljubljana) Irradiated prototype modules continue elsewhere: Irradiated prototype modules continue elsewhere: – Lab measurements – Beam Tests – Systems Tests – Special studies (Fibbing and other things) Other bits and pieces:Other bits and pieces: – ‘plug n’play’ set-up – Humidity sensors, glue, cables, opto-fibres, thermal grease, bar codes...

14. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Radiation Tolerance — Examples Example: Read out noise as a function of dose for a 6 chip hybrid. (No detectors connected) Issues of concern in the ASICs design: Digital current consumption. Digital current consumption.  Re-design Inter-chip communication circuitry. Inter-chip communication circuitry.  Re-design Comparator threshold matching Comparator threshold matching  Threshold correction circuitry for each channel Other things... Other things... SEU Measurement: Looking for bit-flips in certain logical cells during accumulation of total dose. Looking for bit-flips in certain logical cells during accumulation of total dose. Only certain registers can be read back — but measurement gives the order of magnitude Only certain registers can be read back — but measurement gives the order of magnitude SEU are not considered as a serious concern, periodic reset cycles solves the problem. SEU are not considered as a serious concern, periodic reset cycles solves the problem.

15. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Efficiency and Noise Occupancy as a function of Comparator threshold, from Beam Test August 2001 Efficiency calculation only includes perfect strips (>99 %) Beam Tests — Some results Beam Tests at CERN (Geneva) and at KEK (Tsukuba) Evolving from R&D towards parameterisation of detector module performance. Evolving from R&D towards parameterisation of detector module performance. Will continue during the production as a part of the Quality Assurance (QA). Will continue during the production as a part of the Quality Assurance (QA). Irradiated and non-irradiated modules included in the program Irradiated and non-irradiated modules included in the program 5*10 -4 99 %

16. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Beam Tests — Some results (2) Irradiated modules (350 V) m B = 0 T l B = 1.56 T Non-irradiated modules (150 V) m B = 0 T l B = 1.56 T Collected charge vs. incidence angle of the beam Charge sharing: Incident Angle Incident Angle Magnetic Field (Lorenz angle) Magnetic Field (Lorenz angle)

17. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Beam Tests — Some results (3) One strip resolution vs. incidence angle Irradiated modules m B = 0 T l B = 1.56 T Non-irradiated modules m B = 0 T l B = 1.56 T Charge sharing: Increases number of two strip clusters Increases number of two strip clusters Improves the resolution slightly Improves the resolution slightly

18. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Systems Test Small scale Systems Tests @ CERN: Barrel ~ 15 modules End-cap ~ 3 - 4 modules Studies of (among many other things): Prototype Power Supplies Prototype Power Supplies Filtering Filtering Grounding / Shielding schemes Grounding / Shielding schemes Correlated noise Correlated noise Pick-up Pick-up

19. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Towards Serial Production Large scale experiment  Serial production of components: Most components in the SCT system are about to go into production. Most components in the SCT system are about to go into production. In particular, the SCT detector modules (Barrel modules now, End-cap modules to follow) In particular, the SCT detector modules (Barrel modules now, End-cap modules to follow) Silicon sensors: In series production at Hamamatsu and CiS since a few month. In series production at Hamamatsu and CiS since a few month. Quality Assurance (QA) at Universities around the world. Quality Assurance (QA) at Universities around the world. Hybrids: First batches of hybrids are delivered, QA in Japan. First batches of hybrids are delivered, QA in Japan.Baseboards: Production at CERN has just started Production at CERN has just startedASICs: Delivery of production wafers since a few month. Delivery of production wafers since a few month. Wafer screening at LBL, RAL and CERN Wafer screening at LBL, RAL and CERN Situation at present for Barrel module components:

20. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Detector Module Assembly Distributed Production — Module assembly will be done on several sites in parallel The Barrel Module Production clusters:Japan (606 modules) (# of modules to build fully in specification)Scandinavia (404 modules) UK (549 modules) US (663 modules) Four Parallel production lines. Four Parallel production lines. Responsibilities shared within each cluster Responsibilities shared within each cluster Mechanical Assembly Mechanical Assembly Electrical bonding Electrical bonding Quality Assurance Quality Assurance Status: Japan - already started production UK, US and Scandinavia - foreseen to start production in May 2002

21. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Quality Assurance Quality Assurance Procedures: To assure the quality of the final product To assure the quality of the final product Improve production yield. Improve production yield. Catch infant mortality Catch infant mortality Avoid variation in quality Avoid variation in quality The QA list includes: Visual Inspection Visual Inspection Detector I/V Detector I/V Burn-in of ASICs (on hybrid) Burn-in of ASICs (on hybrid) Electrical functionality - at several stages Electrical functionality - at several stages Metrology (x, y and z) Metrology (x, y and z) Long term stability (detector current, noise) Long term stability (detector current, noise) Thermal cycling (-25 ºC  40 ºC, 10 times) Thermal cycling (-25 ºC  40 ºC, 10 times) Full characterisation of electrical performance Full characterisation of electrical performance Everything recorded in the SCT Data Base. Everything recorded in the SCT Data Base. Site Qualification: A cluster shows to the collaboration that it is can build detector modules within specifications, including all QA procedures A cluster shows to the collaboration that it is can build detector modules within specifications, including all QA procedures  Production can start!

22. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University The Scandinavian Cluster University of Bergen: Silicon Detector Testing Silicon Detector Testing Final QA and Electrical Characterisation Final QA and Electrical Characterisation University of Oslo: Mechanical assembly of Sensor/Baseboard sandwich Mechanical assembly of Sensor/Baseboard sandwich Final QA and Electrical Characterisation Final QA and Electrical Characterisation Uppsala University: Metrology / Geometrical acceptance Metrology / Geometrical acceptance Wire - bonding* Wire - bonding* Final QA and Electrical Characterisation Final QA and Electrical Characterisation (*) Hybrids are delivered populated with ASICs from Japan And of course: Re-work, debugging, batch testing, data base handling, logistics...

23. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Summary The SCT is an essential part of the ATLAS tracking system. The SCT is an essential part of the ATLAS tracking system. It is a large scale application of silicon detectors for HEP. It is a large scale application of silicon detectors for HEP. An exhaustive program has shown that it fulfils requirements in: An exhaustive program has shown that it fulfils requirements in: Thermal/Mechanical performance Thermal/Mechanical performance Radiation Hardness. Radiation Hardness. Beam Tests and laboratory measurements Beam Tests and laboratory measurements Small scale Systems Test Small scale Systems Test Many other investigations have shown that the modules ‘do the job’ Many other investigations have shown that the modules ‘do the job’ Detector modules are possible to build in a rational manner. Detector modules are possible to build in a rational manner. Infrastructure for production is (almost) in place. Infrastructure for production is (almost) in place. Production is about to start — with a close eye on crucial parameters

24. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University S-Curves Signal from Calibration Circuitry or Detector Signal from Calibration Circuitry or Detector Add Gaussian noise Add Gaussian noise Scan threshold Scan threshold Count the Occupancy & fit a complementary Error Function. Count the Occupancy & fit a complementary Error Function.

25. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Noise and Gain Threshold scans for several injected chages Threshold scans for several injected chages Extract 50 % occupancy point Extract 50 % occupancy point Output noise from complementary error function Output noise from complementary error function Extract gain and noise Extract gain and noise

26. INSTR02 28/2 - 6/3 2002, NovosibirskLars Eklund, Uppsala University Power Consumption After annealing 3.5 Vcc (V) 55.2Power (W) 560950Icc (mA) 44.0Vdd (V) 750550Idd (mA) After IrradiationBefore Irradiation Typical (acceptable) values for module power consumption