1. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 o The ATLAS IBL Project The 5 th "Trento" Workshop on Advanced Silicon Radiation Detectors Manchester, 24-26 February 2010 G. Darbo - INFN / Genova Conference Site: http://www.hep.man.ac.uk/Radiation-Detectors2010/agenda.html

2. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 2 ATLAS Pixel Detector 3 Barrel + 3 Forward/Backward disks 112 staves and 48 sectors 1744 modules 80 million channels

3. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 3 The ATLAS Pixel Module ATLAS Pixel Module 16-frontend chips (FE-I3) modules with a module controller chip (MCC) 47232 pixels (46080 R/O channels), 50 x 400 µm 2 (50 x 600 µm 2 for edge pixel columns between neighbour FE-I3 chips) Planar n-on-n DOFZ silicon sensors, 250 µm thick Designed for 1 x 10 15 1MeV fluence and 50 Mrad Opto link R/O: 40÷80 Mb/link

4. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 4 Pixel Integration and Installation

5. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 5 Mission impossible… fit an additional layer in between Pixel and beam-pipe: Reduce beam-pipe by 4 mm in radius… and make it possible! Mission impossible… fit an additional layer in between Pixel and beam-pipe: Reduce beam-pipe by 4 mm in radius… and make it possible! IBL: Project History The ATLAS Pixel B-Layer initially designed for replacement September 2007 B-Layer replacement Workshop  outcome: replacement not possible in 1 year shutdown. January 2008: ATLAS Task Force (A. Clark & G. Mornacchi)  Report July 2008 (Bern): preferred (only) option Insertable B-Layer (IBL) February 2009: project approved by ATLAS  May 2009 IBL management organization in place. Now: design fast advancing, IBL Technical Design Report (TDR) draft, interim Memorandum of Understanding (i-MoU) in discussion. Existing B-Layer IBL Iourii Gusakov

6. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 6 Motivation for IBL The existing B-Layer cannot be replaced in a long LHC shutdown (8-months): This was a major finding of the B-Layer task force. Many reasons make it very difficult: Extraction, moving to surface and opening the whole Pixel Detector package. Work on an activated material. Risk of damage (many last moment operations made the process “irreversible” in the final phase of the detector integration). Reasons for an IBL to back-up existing B-Layer: Radiation damage Sensor and electronics degradation of the existing B-Layer reduce detector efficiency after 300÷400 fb -1 (last forecast of LHC integrated luminosity move it more far away) Insurance for hard failures in the Pixel B-Layer The Pixel Detector cannot be repaired in case of cooling, opto-links, module hard failure. Inefficiencies of the B-layer have high impact on many Physics channels. Improve existing B-Layer Physics performance A low mass detector (~50% of existing B-Layer) improves Physics performance.

7. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 7 IBL Layout Beam-pipe reduction: Inner R: 29  25 mm Very tight clearance: “Hermetic” to straight tracks in Φ (1.8º overlap) No overlap in Z: minimize gap between sensor active area. Layout parameters: IBL envelope: 9 mm in R 14 staves. = 33 mm. Z = 60 cm (active length). η = 2.5 coverage.

8. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 8 BP Extraction & IBL+BP Insertion Material from Raphael/Neal The present 7m long section of the beam-pipe will be cut (flange too big to pass inside the existing pixel) and extracted in situ: The new beam-pipe with the IBL will be inserted at its place: A carbon tube (IST) is inserted before the IBL: to support the new detector and to simplify the insertion procedure. IST IBL Support Tube Stave Insert To fix to support, survey reference Alignment wirers Sealing service ring PP1 Collar Ref.: Y.Gusakov, N.Hartman, R.Vuillermet

9. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 9 B-Layer Scenarios Physics performance studies ongoing for the IBL TDR (ATHENA/GEANT4). Preliminary studies (ATLSIM/GEANT3) show improved performance with the addition of IBL (see low mass Higgs b-jet tagging plot on the right). Performance improvement due to low mass and smaller radius: Aggressive reduction of material budget is a must! ATLAS b-inserted as 4-layer R=3.5 cm b-replaced SV1 ε b =70% 2-layers R=3.5 cm and 8 cm 2-old layers SV1 ε b =60% WH(120 Gev) Light jets rejection Ref.: A. Rozanov (*) Material budget used in the simulation

10. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 10 Fit made for 2 < r < 20 cm for L=550fb -1 Gives for IBL @ 3.2 cm (550 fb -1 ):  1MeV =3.3x10 15 n eq /cm 2 (1.6 MGy) Safety factors not included in the computation (σ pp event generator: 30%, damage factor for 1 MeV fluences: 50%) Requirements for Sensors/Electronics Requirements for IBL IBL design peak luminosity = 3x10 34 cm- 2 s -1  FE-I4 architecture & R/O bandwidth: must be understood after Chamonix Integrated luminosity seen by IBL = 550 fb -1  Survive to sLHC phase II Design sensor/electronics for total dose: NIEL dose = 3.3 x 10 15 ± (“safety factors”) ≥ 5 x 10 15 n eq /cm 2 Ionizing dose ≥ 250 Mrad Ref.: Ian Dawson

11. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 11 FE-I4 Architecture: Obvious Solution to Bottleneck >99% or hits will not leave the chip (not triggered) So don’t move them around inside the chip! (this will also save digital power!) This requires local storage and processing in the pixel array Possible with smaller feature size technology (130 nm) Large chip - design methodology: Custom digital layout substituted by automatic place & route of synthesized design. Chip verification is the challenge: analog/digital and mix-mode test bench simulation. Ref.: M. Barbero et al. FE-I3 @ R = 5 cm

12. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 12 FE-I3  FE-I4 FE-I4 Collaboration: Bonn: D. Arutinov, M. Barbero, T. Hemperek, A. Kruth, M. Karagounis. CPPM: D. Fougeron, M. Menouni. Genova: R. Beccherle, G. Darbo. LBNL: S. Dube, D. Elledge, M. Garcia- Sciveres, D. Gnani, A. Mekkaoui. Nikhef: V. Gromov, R. Kluit, J.D. Schipper The first version of full FE-I4 chip will be submitted by end of March 2010 ~70 million transistors, 0.13 µm CMOS technology 6 Cu and 2 Al routing layers. 7.6mm 8mmactive 2.8mm FE-I3 74% 20.2mm active 16.8mm ~2mm ~200 μ m FE-I4 ~89% Chartered reticule (24 x 32) IBM reticule ~19 mm FE-I3FE-I4 Pixel size [µm 2 ]50x40050x250 Pixel array18x16080x336 Chip size [mm 2 ]7.6x10.820.2x19.0 Active fraction74%89% Analog current [µA/pix]2610 Digital current [µA/pix]1710 Analog Voltage [V]1.61.5 Digital Voltage [V]2.01.2 Pseudo-LVDS out [Mb/s]40160

13. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 13 FE-I4-P1 LDO Regulator Charge Pump Current Reference DACs Control Block Capacitance Measurement 3mm 4mm 61x14 array SEU test IC 4-LVDS Rx/Tx ShuLDO +trist LVDS/LDO/10b-DAC CLKGEN proto : PLL core + PRBS + 8b10b coder + LVDS driv low power discriminator The Way to FE-I4: Test Chips

14. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 14 FE-I4 periphery digital 4-pixel region analog 1-pixel 4-pixel region pixel array 336×80 pixels

15. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 15 FE-I4: Sensor Related Specs SpecificationsValueUnitConditions/comments Pixel size50 x 250µm 2 Bump pad opening12µmdiameter Input-QDC coupled Maximum charge100,000e DC leakage current tolerance100nA Pixel array size80 x 320Col x Row Last bump to physical edge≤ 100µm Normal pixel input capacitance range 100÷500fF Edge pixel input capacitance150÷700fFSides for long pixels and top for ganged Radiation tolerance250MradSpecs met at this dose In-time discriminator threshold with 20 ns gate and 400 fF load ≤5000eRegion can still assign small hits below in-time threshold to correct time bin

16. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 16 FE-I4: Discriminator & R/O Specs SpecificationsValueUnitConditions/comments Hit-trigger association resolution25ns Same pixel two-hit discrimination400nsAt 5000 e in-time threshold and when both hits are 20 ke Single channel ENC sigma<300e400 fF load, nominal current Tuned threshold dispersion<100esigma Charge resolution4bits ADC methodToT Average hit rate with 1% data loss 400MHz/cm 2 3.2 µs trigger latency, 100 kHz trigger rate Max number consecutive triggers16 Trigger latency (max)6.5µs Maximum sustained trigger200kHz Serial command/clock input40Mb/s - MHz 1 + 1 input per chip Serial data output160Mb/s1 output per chip Output data encoding8b/10b I/O signals~LVDSCurrent balanced differential

17. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 17 FE-I4: The Pixel Cell 2-stage architecture optimized for low power, low noise, fast rise time. regular cascode preamp. NMOS input. folded cascode 2 nd stage PMOS input. Additional gain, C c /C f2 ~6. 2 nd stage decoupled from leakage related DC voltage shift. C f1 ~17 fF (~4 MIPs dynamic range). 150 µm 13-bit memory/pixel: 4 FDAC, 5 TDAC, 2 cap, 1 HitEN, 1 HitOR Ref.: A. Mekkaoui

18. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 18 Noise and Radiation Results a)ENC on “Collaboration Proto 1” before and after irradiation (200 Mrad) b)Measured ENC for pixels with and without C load c)Simulated ENC and time-walk @ 10 µA/pixel (preamp + amp2 + comparator) ENC @ Low Current (10µA) (loaded ~400 fF) ~ 65 e ~ 90 e (10 µA) 200Mrad, C load ~400fF a) b) c) 20 ns timewalk for 2 ke - < Qin < 52 ke - & threshold @ 1.5 ke - ENC=160e- @ C d =0.4pF & I L =100nA ENC[e - ] C d [F] Q in [C] t LE [s] 100f200f300f 60 100 150 10k 20k30k40k I L = 0 nA 20n 10n 0 I L =100 nA

19. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 19 Module Design: Sensor Technology Independent Decision on sensors after TDR Need module prototypes with FE-I4 (second half 2010) Common sensor baseline for engineering and system purposes 3D / Diamond sensors – single chip modules / Planar sensors – 2 chip modules Sensor/module prototypes for ~10% of the detector in 2010 Stave prototype tested with modules and cooling Credits: M.Garcia-Sciveres – F. Hügging Single chip module: Edge < 325 µm Double chip module: Edge < 450 µm

20. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 20 Sensors 3 sensor technologies considered for IBL Planar, 3D and Diamonds Full scale prototypes with FE-I4 – Decision on spring 2010 Some specifications agreed: Max fluence > 5 x 10 15 1MeV neutrons / cm 2 Max power after full life dose < 200 mW/cm 2 Low dead area in Z: slim or active edge Maximum bias voltage (system issue) : 1000 V Sensor R&D and prototype work for IBL are presented in many talks in the Workshop…

21. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 21 Bump Bonding Large volume bump-bonding experience from Pixel Detector (see table): PbSn and Indium bumps: PbSn  AgSn Program to qualify for the larger FE-I4 and different sensor technologies. Setting up with mechanical/electrical dummies, but finally real parts needed: thermo-mechanical process strongly dependent on actual metal layers of electronic chip and sensor. Goal to go below 190 µm of the Pixel Detector: target to 90 µm. “dummy – sensor” (monitor wafer) “dummy – sensor” (monitor wafer) ATLAS Pixel bump-bonding production – Ref: Jinst 3 P07007 (2008) Prototype test of advanced AgSn bumping with 90µm FE-I4 size dummies.

22. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 22 Thermal Figure of Merit and Thermal Run-away Thermal runaway happens in sensors if not adequately cooled Leakage current shows exponential behavior. Stave thermal figure of merit (Γ = [ΔTcm 2 /W]) main parameter for thermal performance. Power design requirements for IBL: Sensor Power200 mW/cm 2 @ -15  C FE power400 mW/cm 2 Stave prototype qualification program: Titanium / carbon fiber pipes (D = 2÷3 mm) Cooling CO 2 and C 3 F 8 Carbon foam density: 025÷0.5 g/cm 3 Radiation length: 0.36÷0.66 %X/X 0 Pipe + stave structure + coolant Evaporation T = -40 ºC  = 30.0  Ccm2/W  = 18.5  Ccm2/W  = 3.2  Ccm2/W Thermal Runaway Plot Ref.: D Giugni, H. Pernegger, M. Gilchriese IBL including safety

23. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 23 Stave Structure Stave structure made of carbon foam + cooling pipe (carbon fiber or titanium boiling channel) The stiffness is provided by a carbon fiber laminate: Fiber YS-80A; resin EX-1515; lay-up (0/60/-60) S2 Carbon foam diffuses the heat from the module to the cooling pipe Poco Foam  =0.55g/cm 3 ; K=135/45 W/mK OR Kopers KFOAM L1-250  =0.245g/cm 3 ; K=30 W/mK Module (sensor + bumps + FE-I4) Carbon foam Omega CF laminate Ti or CF pipe

24. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 24 Stave Prototype Options STAVE CARACTERISTICSSIMULATION RESULTS Pipe ID/OD [mm] Omega Thickness [µm] Foam Density [g/cm 3 ] CoolantX/X 0 [%]Thermal Figure of Merit (Γ) [ºCcm 2 /W] Bare Stave with Coolant Full layer (+ Module + Flex) CF pipe, heavy foam 2.4 / 3.01500.55C3F8C3F8 0.481.05617.25 CF pipe, light foam 2.4 / 3.01500.25CO 2 0.360.95618.56 Ti 3mm pipe, light foam 2.8 / 3.03000.25C3F8C3F8 0.661.2762.79 Ti 2mm pipe, light foam 2.0 / 2.23000.25CO 2 0.571/1663.22 Module parameters Sensor thickness = 250 µm FE-I4 thickness = 90 µm Flex Hybrid (η = 0) = 0.18 % of X 0 Additional technical requirements (prototype work) Max pressure of cooling pipe: 100 bar. Develop pipe joints and fittings. Gravitational / thermal deformation < 150 µm. Isolation of the carbon foam from sensor high voltage. Mock-up for thermal measurements. Carbon Foam 0.25g/cm 3

25. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 25 When IBL in ATLAS? IBL plans to be ready for installation by end of 2014. Cannot be much before without compromising performance A shut down of the machine of 8 month needed (4 to open/close ATLAS) LHC plans after Chamonix are not clear: how peak and integrated luminosity increase and when machine shutdown will be scheduled: Only plans up to 2012 are known. Many LHC upgrades need shutdowns: Linac4, Collimators phase II, new interaction region quadrupole triplets, etc. Probably in one year from now we will know next 5 years plans. Chamonix Agenda: http://indico.cern.ch/conferenceDisplay.py?confId=67839 Summary of the Chamonix Workshop at Cern: http://indico.cern.ch/conferenceDisplay.py?confId=83135

26. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 26 Conclusions

27. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 27 BACKUP SLIDES

28. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 28 R. Vuillermet The support carbon tube is fixed in 2 point of PP0 and on PP1 walls on side C and A. The structural pipe with a support system is moved out from the support carbon tube.. The new beam pipe (in any configuration with OD up to 82,5 mm) is inserted from A-side. It has 2 supports at PP0 area and 2 floating wall at PP1 on side A and C. Two global support / installation scenarios: IBL support tube (1) / no tube (2): An IBL support tube would have advantage on stiffness and simplicity/safety for IBL installation, but drawback are envelope needs (~1÷1.5 mm) and increase of radiation length Procedure studied on mock-up at bld.180 - procedure (1) animation: The beam pipe flange on A-side is to close to the B-layer envelope - Need to be cut on the aluminum section A structural pipe is inserted inside the Beam Pipe and supported at both sides. The support collar at PP0 A-side is disassembled and extracted with wires at PP1. Beam pipe is extracted from the C-side and it pulls the wire at PP1 New cable supports are inserted inside PST at PP0. A support carbon tube is pushed inside the PST along the structural pipe. Started to setup a 1:1 mock-up of Pixel/beampipe/PP1 in Bat 180 A-side C-side Installation Scenarios

29. The ATLAS IBL Project – 5 th Trento Workshop G. Darbo – INFN / Genova Manchester, 24-26 February 2010 29 IBL Organisation Structure Module WG (2 coordinators) FE-I4 Sensors Bump-Bonding Modules Test & QC Irradiation Module WG (2 coordinators) FE-I4 Sensors Bump-Bonding Modules Test & QC Irradiation Stave WG (1 Phys + 1 Eng.) Staves Cooling Design & Stave Thermal Management HDI Internal Services Loaded Stave Test & QC Stave WG (1 Phys + 1 Eng.) Staves Cooling Design & Stave Thermal Management HDI Internal Services Loaded Stave Test & QC IBL Integr.-Install. (2 Eng.) Stave Integration Global Sup. Beam Pipe (BP) Ext.services inst. IBL+BP Installation Cooling Plant Test & QC IBL Integr.-Install. (2 Eng.) Stave Integration Global Sup. Beam Pipe (BP) Ext.services inst. IBL+BP Installation Cooling Plant Test & QC Off-detector (1 Phys + 1 E.Eng.) Power DCS ROD Opto-link Ext.serv.design/proc. Test Beam System Test Off-detector (1 Phys + 1 E.Eng.) Power DCS ROD Opto-link Ext.serv.design/proc. Test Beam System Test IBL Management Board Membership: IBL PL + IBL TC 2 coordinators from each WG Plus “extra” members IBL Management Board Membership: IBL PL + IBL TC 2 coordinators from each WG Plus “extra” members Membership IBL Project Leader: G. Darbo IBL Technical Coordinator: H. Pernegger “Module” WG (2 Physicists): F. Hügging & M. Garcia- Sciveres “Stave” WG (1 Phy. + 1 M.E.): O. Rohne + D. Giugni “IBL Assembly & Installation” WG (2 M.E. initially, a Phy. Later): N. Hartman + R. Vuillermet “Off-detector” WG (1 Phy. + 1 E.E.): T. Flick + S. Débieux “Extra” members: Ex officio: Upgrade Coordinator (N. Hessey), PO Chair (M. Nessi), Pixel PL (B. Di Girolamo), ID PL (P. Wells), Pixel Chair (C. Gößling) Offline “liaison” Pixel Off-line coordinator: A. Andreazza TDR editor (temporary): K. Einsweiler Whole project divided into 4 working groups IBL Management Board has 10 members, plus “extra” and ex-officio members. Frequent meetings (every ~14 days) in this phase of the project.