MFT WG5: ladder disk and global assembly Stéphane BOUVIER & Sébastian HERLANT MFT WG7: Mechanics and Thermal studies Jean-Michel BUHOUR & Emili SCHIBLER ALICE ITS, MFT and O2 Asian Workshop
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Sensor+FPC Hybrid Integrated Circuit (HIC) with 1 to 5 sensors each. Carbon plastic CFRP stiffener/protector. 3 Alice Muon meeting - Chia - 26th May 2015
ALICE ITS, MFT and O2 Asian Workshop Cold plate Foam Disk support Cooling pipes Manyfold
Simplified ladder model Water velocity in pipes 1 m/s Power distribution 85%(dig)+ 15%(ana) Influence of the water pipe diameter 5 X Z 40 mW/cm 2 50 mW/cm 2
6 Disks 0, 1 & 2 Alice Muon meeting - Chia - 26th May 2015
Pipe diameter Ø1=> Ø2 : Tmax -1.5 / -2°C Composite material - Tmax > 50°C !! - Non cooled sensor impossible with ‘standard’ composite High thermal conductivity composite required (K13D2U) for ‘straight pipes’ configuration 7
Analog part Digital part ALICE ITS, MFT and O2 Asian Workshop WG5 weekly meeting - 12th Mayl 2015 Stiffener in carbone fiber material = cold plate 467MP Heater Dummy sensors FPC Glue 467MP Constantan constantan wire, 100 µm diameter, 62.4 /m Heater, 28 13 x 140 mm, 170 µm thickness Thermal dissipation of a sensor Digital part : 1 mm width,85 % of the power dissipation 2 lenghts of constantan wires Analog part : 14 mm width, 15 % of the power dissipation
ALICE ITS, MFT and O2 Asian Workshop Thermal tests, general diagram Thermal camera Tc recorder Power unit Pomp and chiller HIC Cold plate Water pipe ThermoCouple
ALICE ITS, MFT and O2 Asian Workshop
Micrometric tools to Place sensors (ITS) ALICE ITS, MFT and O2 Asian Workshop Vacuum table(ITS) To keep sensor in position To optimize laser soldering Worktable MFT To align sensors/Flex circuit/laser soldering mask
ALICE ITS, MFT and O2 Asian Workshop Procedure: Sensors alignment Add Flex and Soldering grid. Check alignment of pads sensors and holes Install balls (200µm) on the special tool Put the balls on the soldering grid Install the vacuum box/ make vacuum Soldering the balls
ALICE ITS, MFT and O2 Asian Workshop Features for laser soldering operation: Quality of the FPC Perfect Ni/Au finishing in the hole. Accurate position of the hole. High cleanness (Washing Workshop). Good precision for alignment and stacking of Sensors/Flex/Soldering grid/balls. Clean worktable and sensors Ball FPC hole Soldering grid hole
ALICE ITS, MFT and O2 Asian Workshop Terminal To monitor laser soldering Results: Worktable to be redesign to improve mechanical tolerance A new production of FPC with better quality First HIC (5 chips with just connections soldered )
ALICE ITS, MFT and O2 Asian Workshop FPC : * Several prototypes in copper for mechanical purposes and first soldering, * Final version with traces in aluminum Very expensive, try to reduce the surface
ALICE ITS, MFT and O2 Asian Workshop * Allowed temperature for FPC integrity: up to 140 °C * Technical choice: Gluing components with conductive glue : H20E * Produced by Epoxy Technology * Provided by FTPolymer in France * Can be cured at 80°C for a minimum of 3 hours * Commonly used for HEP. * Specific SMD components : Pd/Ag plating for gluing curing. * Under discussion with a company for trial
ALICE ITS, MFT and O2 Asian Workshop * Laser soldering worktable * FPC ears cutting system * Worktable gluing support * Tools to handle and store the ladders
First MFT ladder (5 sensors) by November Production at CERN. 504 MFT ladders (2 to 5 sensors). This includes half MFT as spare and 20% of spares ladders. 2 technicians and 1 physicist 10 months 18 ALICE ITS, MFT and O2 Asian Workshop 2015
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ALICE ITS, MFT and O2 Asian Workshop Design of the prototype done and fabricated for disk 0 Disk support Ladder positioning reference FPC tail cutting tool Dummy cold plate Disk support positioning reference Disk support reference plane
ALICE ITS, MFT and O2 Asian Workshop First assembly of FPCs on a disk : Position of one FPC defined by 2 pins and the connector => risk of overconstrain Tests done, assembling work, => design validated (pins, screw, lenght of FPC)
ALICE ITS, MFT and O2 Asian Workshop On going gluing tests HIC Glue Cold plate Kapton adhesive HIC Glue Cold plate Ladder removable mechanically Removability in whole or in part of the ladder insured by pulling the kapton adhesive Case 2 : Glue only Case 1 : kapton adhesive + glue 1-a HIC Glue Cold plate Kapton adhesive 1-b Others cases... GlueType Eccobond 45 (ITS) Epoxy Adhesive tape 467MP (used in STAR) Transfert adhesive LEDPAD SFH5 2-sided adhesive, acrylic film APTEK 2724 A/B (used in STAR) Silicone Dow Corning SE 4445 (used in ATLAS) Silicone Several glue tested
Disk assembly process, design and specific tooling by April Production half-disks. One week per half-disk assembly, one week for the survey and one week for qualification. Global assembly 4 months on surface and 6 months in the cavern (october 2019). 23
ALICE ITS, MFT and O2 Asian Workshop