1. Development of the silicon microstrip super- module prototype for the HL-LHC University of Geneva: G. Barbier, F. Cadoux, A. Clark, Y. Favre, D. Ferrère, S. Gonzalez- Sevilla, G. Iacoubucci, D. la Marra, M. Pohl, M. Weber KEK: Y. Ikegami, Y. Takubo. S. Terada, Y. Unno University of Tsukuba: K. Hara Osaka University: M. Endo, K. Hanagaki Outline: 1.Background: HL-LHC and resulting tracking detector upgrades 2.A proposed silicon microstrip implementation for HL-LHC: module and super-module design features 3. Where are we? 4. Comparison with HL-LHC requirements 5. Future design evolution 6. Feasibility for a construction and production success 8 th "Hiroshima" Symposium on Development and Application of Semiconductor Tracking Detectors (HSTD-8), Taipei, Taiwan, December 3-8, 2011

2. 2 2 A Clark, HSTD8 Symposium, Dec 2011 Machine and Detectors at HL-LHC 2011 √s=7 TeV L peak ~ 3.65 x 10 33 cm -2 s -1 L int ~ 5 fb -1 2012 √s=8 TeV L peak ~ 5 x 10 33 cm -2 s -1 2014 - 16 √s=14 TeV L peak > 5 x 10 33 cm -2 s -1 2018 - 20 L peak ~ 2-3 x 10 34 cm -2 s -1 L int ~ 300 - 400 fb -1 > 2022 L peak ~ 5 x 10 34 cm -2 s -1 L int ~ 3000 fb -1 (luminosity levelling) – 25 nsec bunch spacing – Tracking performance should be maintained with up to ~200 collisions per bunch crossing

3. 3 3 A Clark, HSTD8 Symposium, Dec 2011 Benchmark layout and performance requirements (1)

4. 4 4 A Clark, HSTD8 Symposium, Dec 2011 Benchmark layout and performance requirements (2)

5. Features: Detectors are mounted back-to-back, true stereo reconstruction  Space point integrated by the module assembly with the precision of the jigs (~1 µm)  Sensor 96 x 96 mm 2, (short) strips 24 x 0.08 mm 2 Precise module location on the local structure  Thanks to centering bushes: origin + alignment Bridge hybrid allows FE thermal path different from Si (stabilty consequences) NB: Direct mounting save material and no show stopper in term of thermal performance Low CTE material and Good thermal conductivity: Si, TPG, CC, AlN  Max Z deformation 1.4  m @ -35°C Hybrid pigtails + connector for electrical connections (option)  Modularity and flexibility Module assembly known and simplified in term of procedure and QA: Inherited from SCT barrel Prototype Module Design 5 5 A Clark, HSTD8 Symposium, Dec 2011

6. Module Assembly Parts – low material budget TPG and Ceramic facings Sensor to baseboard assembly Populated hybrid with CC bridge 6 6 A Clark, HSTD8 Symposium, Dec 2011

7. Module thermal FEA with and without CC bridge Recent FEA calculations investigated by Franck Hybrid glued on the Si-sensor CO 2 based -35°C as coolant temp. 2mm ID pipe Chip: 0,3W Sensor temperature [-19, -22 °C] No wire bonds connected here… Bridge hybrids Sensor temperature [-22, -24 °C] Some gap in here… Temperature offset and distribution is slightly larger but acceptable as compared with the bridged FEA Recall: Thermal run-away was found to be around a factor 4 to the LHC Si power density for bridged design 7 7 A Clark, HSTD8 Symposium, Dec 2011

8. Module Electrical Performance Modules constructed 8 8 A Clark, HSTD8 Symposium, Dec 2011 Module made at KEK Additional modules are under industrialization process with local Japanese companies Essential to survey for future production evaluation

9. Col 0 Col 1 Col 0 Col 1 Typical noise results from the 4 module test box 564 to 590e- Identical noise inside a single module test box or when combined in the 4 module test box 9 9 Hybrid 0Hybrid 1 Module Electrical Performance Module Performance A Clark, HSTD8 Symposium, Dec 2011

10. Module Electrical Performance Module Irradiation 10 A Clark, HSTD8 Symposium, Dec 2011

11. Super-module Design Features Super-Module Made of 12 double-sided modules assembled on a local support Coolant tube structure Hybrids & FE ABCN Local Support 1.2 m long with 960 ABCN readout chips Modular concept. All parts decoupled from module design and are modular: cooling, local support, service bus, powering units, SMC during prototyping, flexibility of evolutions: electronics, service bus, cooling, mechanics versions parallel assembly at all stages: components prototyping & procurement, fabrication & QA Full module coverage in Z Space points: distance to the stereo side of 400 microns: space point resolution equivalent to SCT Rework : ability to easilyrework up to the commissioning after integration End-insertion: >1m20 stiff Local Support allows simple support structure and service modularity Low thermo-mechanical stresses:.service bus almost free, cooling pipe uses sliding joins. Super-Module Controller Bus cable 11 A Clark, HSTD8 Symposium, Dec 2011

12. CAD view of the SM2.0 (Modules have been removed for clarity) Cross beam (or « wings ») Cooling Plates x6 (prototyped in aluminum… CC2D at the end) Central pipe in T300 (key part!) Every sub part assembled with DP490 glue (with jig and centering pieces) Cooling pipe Cover (T300) Cross beam x7 (in T300 prepreg) Guiding pipe (T300) Joint pieces in plastic (polycarbonate for proto) When assembled… Modules (TPG, Si, Hybrid,…) Super-module Mechanical Structure Design 12 A Clark, HSTD8 Symposium, Dec 2011

13. End Insertion also developed for “stave” concept Guide rail The SM slides w/o stress into the structure (locking in 3 positions) End Insertion using a Removable inner guide rail Safe handling Cable bus envelope Super-module Mechanical Structure Design 13 A Clark, HSTD8 Symposium, Dec 2011 End Insertion as a reminder

14. Super-module Mechanical Prototype Light CFRP local support structure (UniGe – Composite Design) (UniGe – Composite Design) Total support 0.18 X 0 Easy handling… Module + Cooling plate and loop independent from LS loop independent from LS Concept validated with end- insertion interfacing dummy barrel locking system 14 A Clark, HSTD8 Symposium, Dec 2011

15. FEA ’ s outcome on a 1200mm SM Load caseDeflection (micron) Max Stress (Mpa) 16°7711 Vertical8012 Horizontal1110 Eigenvaluef1: 57 hz- 1G Carbon fiber Layup (M55J) Module material assembly Modal shape Super-module Load Tests and FEA 15 A Clark, HSTD8 Symposium, Dec 2011 Major load and distortion measurements underway to compare/input in FEA, and aid next design iteration Results very positive Results very positive

16. Grease SampleTh. Cond. [W/mK]Comments DC3400.7Used on SCT DC340 irradiated0.8Polymerized @ 1.10 15 1Mev n eq /cm 2 WLPG1.2Colza oil with graphite. Leaking oil… WLPG irradiated1.05Pasty but ok after irradiation WLPF0.5Non-silicone + metal oxyde Electrolube HTCP1.5Non-silicone + Zinc oxyde Measurements of thermal conductivity cross-checked with FEA (K. Streit) 16 Focus – IBL baseline Cooling and Mechanical Performance F F 2.3mm OD Ti-pipe with ~50-70 micron Grease area ~70mm 2 per pipe Irradiated Irradiated at 1x10 15 1MeV n eq /cm 2 Thermal conductivity satisfactory Young Modulus increases from ~40 Mpa to 160 Mpa Very positive result, being input into FEA calculations Samples of HTCP irradiated up to 1.2x10 16 1MeV n eq /cm 2 for IBL Samples drying and dryer but OK with SCT fluences A Clark, HSTD8 Symposium, Dec 2011

17. Super-module Electrical Prototype Module support jig Double sided support structure Module removed from 4 Module Box 1st module mounted on the structure 4 mounted modules Modules with wiggly service buses, BCC boards and DC-DC 17 A Clark, HSTD8 Symposium, Dec 2011

18. 18 Aim: study of 8-module readout Status: 4 modules so far read out successfully successfully Hybrid noise versus col Hybrid noise versus chip id Noise is uniform ENC/hybrid < ~ 600e- See talk of Sergio Gonzalez Sevilla at this conference Super-module Electrical Prototype Performance S. Gonzalez Sevilla, Y. Takubo) + collaboration for r/o between “supermodule” and “stave” R&D projects A Clark, HSTD8 Symposium, Dec 2011

19. 19 Comparison with HL-LHC Requirements A Clark, HSTD8 Symposium, Dec 2011

20. 20 Next Steps A Clark, HSTD8 Symposium, Dec 2011 Status: Close to demonstrating feasibility and practicability of super module solution for ATLAS Phase II tracking detector for ATLAS Phase II tracking detector Will allow technical comparison with competing technologies Will allow technical comparison with competing technologies Evolution: Evolution of sensor design Development of front-end electronics (ABCN 130 nm design) Development of front-end electronics (ABCN 130 nm design) Evolution and implementation of read-out architecture Evolution and implementation of read-out architecture Members of Super Module R&D strongly involved in all these developments Members of Super Module R&D strongly involved in all these developments Next steps: 2012: Thermal and electrical measurements on 2 nd iteration LS with modules and dummy thermal modules (CO 2 cooling) and dummy thermal modules (CO 2 cooling) : 2 nd iteration module design studies : 2 nd iteration module design studies : 2013: Development of pre-production LS and module prototypes optimized for : 2013: Development of pre-production LS and module prototypes optimized for material, electrical (ABCN 130) and thermo-mechanical performance after material, electrical (ABCN 130) and thermo-mechanical performance after irradiation, and construction simplicity irradiation, and construction simplicity : issues: adapt to layout criteria : issues: adapt to layout criteria : optimization of the service bus : optimization of the service bus : LV services (DC-DC or SP powering) : LV services (DC-DC or SP powering) : HV services (4 module per HV line?, 1 HV line per LS?) : HV services (4 module per HV line?, 1 HV line per LS?) : tradeoff between performance (material, noise pickup) and robustness : tradeoff between performance (material, noise pickup) and robustness (next slides)

21. Module Design Evolution Power Card Comments: - Symmetry between the two rows is quite important - Power card (DC-DC or SP) implantation is quite challenging and needs study - Pigtail flexibility is essential to pass over the cooling plate - EMI investigation is essential when considering DC-DC Cooling plates and tubes Flexible pigtail with connector and stiffener HCC CC + hybrid flex “U” bridge Stiffener linking the 2 sides possibly free from the local support HCC 1 st draft layout with ABCN130, HCC under investigation Input Filtering GND AC coupling with HVret 21 D. Ferrere S. Gonzalez Sevilla A Clark, HSTD8 Symposium, Dec 2011

22. Cooling In Super-Module Design Evolution Service bus TTC, Data & DCS PS cable SMB Module #1Module #2Module #8 HV cable DCDC Extrapolated version with ABCN130 & HCC DCDC BCC board Cooling In Service bus TTC, Data & DCS fibers PS cable DCS, Interlock Cooling In Opto SMC SMC Hybrid Cooling Out HV cable Module #1Module #2Module #12 GBT SCA PSPS HCC PSPS PSPS 22 A Clark, HSTD8 Symposium, Dec 2011 F. Cadoux, Y. Favre, D. Ferrere

23. Design Evolution – 3D Models Will serve as input for thermal and thermo-mechanical FEA 23 1 st version of new module design using 3D Integration of modules on the cooling plates and optimized LS Integration of supermodule with Local Support A Clark, HSTD8 Symposium, Dec 2011

24. Material Budget Estimation ItemRad. length [% X0] Module with CC bridge (12mm width)-1.59 Module without CC bridge1.49- Local support0.18 Cooling plates0.25 Bracket, inserts (interface to cylinder)0.08 Cooling pipe (Ti 2mm)0.04 Cable bus Al/Cu0.19- Cable bus Cu only-0.31 Total2.232.45 From Y. Unno (evolving) NB: The sensor thickness is considered 320  m. If 250  m one gains 0.15%! The list above does not include the power cards: serial power interface or DC-DC card Module without CC bridge means that the hybrid flex is directly glued on top of the Si-sensor. This must be investigated. Al/Cu bus is a multilayer flex which is the IBL baseline. 24 A Clark, HSTD8 Symposium, Dec 2011

25. Module Production and Organization 25 Assm Sites Collaborating Institutes CERN SM shipment Individual component QA and checks Module assembly Module metrology Wire bonding Thermal cycling Module metrology Electrical QA and inspection Storage Operations Module assembly LS inspections and basics checks Pipe checks Service checks SMC hybrid functionality checks Module assembly on LS with pipe Service assembly SMC hybrid assembly SM metrology SM QA Storage until shipment Next SM assembly SM reception tests Barrel structure assembly Structure alignment survey SM end insertion Commissioning the full barrel Operations Integration Flexible Parallel prototyping, procurement, assembly possible for all parts of the supermodules SCT Yield ~ 96 to 98% Modules/supermodules replaceable at all stages, even when assembled on barrel Simplification and flexibility of prototyping (e.g. prototype changes to SMC-GBT, service bus, LS, pipe) Flexibility to layout and production changes From D. Ferrere A Clark, HSTD8 Symposium, Dec 2011

26. Conclusions 26 1.The double sided-module program is close to demonstrating feasibility for HL-LHC The noise performance on single module test box, combined module test box or on the super-module prototypes using DC-DC is as expected and below ~600e- Expected good mechanical stability for modules, and supermodules on LS (design is optimised for thermal stability) Flexibility in design (true stereo space-points, possibility of z-overlaps etc) Some key questions remain, independent of super module (services, layout, trigger …) 2. New layout considering a realistic “pre-production” design has started ABCN130, HCC and a dedicated service competitive material budget (service material is one of the keys material to be worked- out) 1. Assembly parallelism and flexibility Possible at all stages of prototyping, assembly and integration Maximizes quality, minimizes risks 2. Much still to be done …… A Clark, HSTD8 Symposium, Dec 2011

27. 27 A Clark, HSTD8 Symposium, Dec 2011 BACKUP

28. Max stress in the TPG ~16 MPa  much lower than the TPG tensile strength (40 MPa) Module Thermo-mechanical FEA Checks Von Mises stresses in TPG plane Deflection in the module A module elongation of ~10 microns is probed at the opposite side of the module origin Z deformation top side Z deformation bottom side Max deformation / bow is less than 1.5micron in the sensor baseboard 28 A Clark, HSTD8 Symposium, Dec 2011

29. Load testing applied to the Prototype (several weight, locations,…) SM onto the granite table @ Unige (+ its assembly jig) Super-module Load Tests and FEA 29 A Clark, HSTD8 Symposium, Dec 2011 F. Cadoux, G. Barbier

30. F1 How does it compare with tests??  Only check / one F1 location  C1: OK while… C2: NOK so far!  Fine tune the wing stiffness  wing rotation (F applied on bridge end) under evaluation… How does it compare with tests??  Only check / one F1 location  C1: OK while… C2: NOK so far!  Fine tune the wing stiffness  wing rotation (F applied on bridge end) under evaluation… F1 Preliminary Pretty good agreement! (FEA : 0,5-0,6mm / Test: 0.65mm) C1 C2 Same Load testing applied to the Prototype but “FEA wise” (several weight, locations,…) Super-module Load Tests and FEA 30 A Clark, HSTD8 Symposium, Dec 2011 F. Cadoux, G. Barbier

31. Service Bus Development Inputs for future design: HCC integrated on the hybrid together with ABCN130 Direct hybrid pigtail connection to service bus – 1 connector for 2 hybrids Mass optimization to be considered: LV traces (Al vs Cu), connectors, bus dimension Multi-drop LVDS to think (without LVDS fanout) Steer the CTE mismatch between service bus and super-module local support HV line insulation: via + open pads and connectors Impedance adaptation for LVDS lines: Point-to-point and multi-drop Shield plane for LVDS and HV. EMI investigation (simulation, measurements, …) Service bus temperature should be estimated and stay homogenous DC-DC or SP interface to hybrid, bus and cooling? Fabrication issue to be investigated: Al mixed with Cu versus service bus length Two types identified: Multilayer flex with Al-layers for LV supply and Cu-traces for the other lines (Like IBL) Multi-stack of 2-layers: 1 with Al for LV supply assembled via connectors to two-layers Cu. NB: Assembly precision need to be better than ~ ¼ of the connector pitch 31 A Clark, HSTD8 Symposium, Dec 2011

32. References 32 Super-module: ATLAS public note: ATL-UPGRADE-PUB-2011-002 “Design and assembly of double-sided silicon strip module prototypes for the ATLAS upgrade strip tracker” TWEPP Poster (S. Gonzalez Sevilla): 2011 JINST 6 C11002 http://iopscience.iop.org/1748-0221/6/11/C11002/ Thermal grease: ATLAS public note: ATL-UPGRADE-PUB-2010-002 “Thermal Grease Evaluation for ATLAS Upgrade Micro-Strip Detector” A Clark, HSTD8 Symposium, Dec 2011