1. Stephan Haensel - LP Subsystems Meeting - DESY Silicon Envelope for the Large Prototype TPC @ DESY S. Haensel 1, T. Bergauer 1, M. Dragicevic 1, M. Krammer 1, T. Barvich 2, A. Dierlamm 2, F. Hartmann 2, B. Ledermann 2, T. Müller 2, H.J. Simonis 2 1 Institut fuer Hochenergiephysik (HEPHY), Vienna, Austria 2 Institut fuer Experimentelle Kernphysik (IEKP), Universitaet Karlsruhe, Germany LP Subsystems Meeting – DESY 25/26.02.2008

2. Stephan Haensel - LP Subsystems Meeting - DESY Contents Introduction Silicon Envelope Cosmic Setup Done & To Do

3. Stephan Haensel - LP Subsystems Meeting - DESY Introduction The SiLC collaboration will participate at the Large Prototype TPC (LPTPC) at the EUDET facility at DESY II. SiLC will design, build and install position sensitive detector modules around the LPTPC made of silicon microstrip sensors that can be used as telescope. The design will allow an easily exchange of the modules to enable tests of different sensor- and chip- designs. This setup will also help to verify if a silicon envelope for a future linear collider TPC is reasonable.

4. Stephan Haensel - LP Subsystems Meeting - DESY Top view of the Setup (Drawing from: http://www-flc.desy.de/tpc/) ID of magnet inner bore 850 mm measured minimum 846 mm SiLC detectors2 x 35 mm clearance inside of SiLC 780 mm extra clearance 2 x 5 mm OD of field cage 770 mm field cage wall2 x 25 mm ID of field cage 720 mm radial dimensions:

5. Stephan Haensel - LP Subsystems Meeting - DESY Silicon Envelope four silicon modules will be installed: -two in front and two behind the TPC, with respect to the e - -beam  two independent support structures are needed -on each side:  one horizontal module consisting of two daisy-chained sensors  and one vertical module consisting of one sensor movable support system is needed because it must be possible to scan the TPC -the TPC and the magnet will move relative to the beam TPCMagnet Beam Rails Module -the sensors have to stay inside the beam line  sensors must be movable orthogonal to the beam and along a curved rail  this movement must be coupled with the movement of the TPC and the magnet  in addition the two sides have to move independently from each other

6. Stephan Haensel - LP Subsystems Meeting - DESY Readout - Plan A -> SiLC Chip + Readout Next Chip: -) 128 channels in 130nm CMOS -) Improved shaper (reduced noise) -> first test beam foreseen in Oct. 08 @ CERN Current Chip: -) 4 channels in 130nm CMOS -) functionality verified in beam tests (from: Thanh Hung Pham @ 6th SiLC meeting) (from: A. Savoy-Navarro @ 6th SiLC meeting)

7. Stephan Haensel - LP Subsystems Meeting - DESY Readout - Plan B -> Adopted CMS Readout based on APV25 readout chip components:green:available orange:to be designed red:still searching for If two working CCUMs can be found: -) two ICBs will be designed -) it has to be verified that the system works with the needed cable lengths (by Alexander Dirlamm) Caption: ICC…InterConnect Card ICB…InterConnect Bus AOH…Analog Optohybrid CCUM…Central Control Unit Module FED…Front End Driver FEC…Front End Controller

8. Stephan Haensel - LP Subsystems Meeting - DESY Readout – Emegency Plans If NO CCUMs can be found! Plan C: use APV25 readout chips with ARC-System (test setup used for the module quality assurance during the CMS module production) same module design can be used hardware available (without cables)  source code of the readout is missing (difficult or even impossible to get from Aachen) Plan D: ALIBAVA - A readout system for microstrip silicon sensors  completely new module design needed – ALIBAVA uses Beetle chip like used in LHCb  ± expensive (we have nothing which we could recycle)

9. Stephan Haensel - LP Subsystems Meeting - DESY 2D Layout Magnet Beam 1 Sensor Module 2 Sensor Module radial dimensions: magnet inner bore425 mm measured minimum423 mm SiLC detectors 35 mm on radius clearance inside SiLC390 mm  it is possible to build an envelope which only needs 25 mm on radius  would give an essential 5 mm clearance to surroundings sliding carriage TPC Sensor Readout In the moment we are working with readout Plan B: based on APV25 (CMS-hybrids) IEKP Karlsruhe will provide the readout system it is foreseen to replace parts of the CMS readout system with newly developed electronics containing the SiLC readout chip in the future

10. Stephan Haensel - LP Subsystems Meeting - DESY Modules Sensors 6 single sided AC coupled sensors from Hamamatsu Japan size: 91.5 x 91.5 mm, thickness: 320 μm 1792 readout strips with a strip pitch of 50 μm first setup: only 768 channels can be read out  the readout sensitive area is reduced to 38,4 x 38,4 mm² (only the intersecting readout area of the two modules on top of each other is interesting)

11. Stephan Haensel - LP Subsystems Meeting - DESY Modules Front-End Hybrids including Pitch Adapter Start up: hybrids leftover from the CMS Tracker End Cap module production will be used  already assembled and bonded Later on: replacement with newly developed FE chips

12. Stephan Haensel - LP Subsystems Meeting - DESY Modules Intermediate Pitch Adapter to connect a pitch of 143  m (CMS-R2) with a pitch of 50  m (new HPK) 2 different PA ordered: ILFA GmbH  4-layer printed circuit board (PCB)  two layers of Cu-lines with 100 μm pitch glued staggered and shifted on top of each other Helsinki Institute of Physics (HIP), Academy of Finland  Aluminium on quartz

13. Stephan Haensel - LP Subsystems Meeting - DESY Plan B - intermediate pitch adapters Pitch Adapter from HIP - 7(+2 damaged) received 7.2.08 optical inspection revealed problems on ALL PA -> problems during the production procedure next steps: -) reprocessing from HIP -) electrical verification of the number of bad channels if HIP-PA are not usable -> pitch adapter from ILFA will be used - 4 received 1.8.08  they are 11mm larger -> increasing module width optical inspection revealed no problems PA were electronically tested from ILFA (to be verified) PA from HIP

14. Stephan Haensel - LP Subsystems Meeting - DESY Modules Isoval ® 11 Frame Isoval ® 11 is a composite of resin epoxy reinforced with a woven fibreglass mat high rigidity low mass insulator easy to mechanically process modules are not glued but get clipped to the frame with 3 mm thick Isoval ® 11 pads which get screwed to the frame -> easy exchange of modules to enable tests of different sensors and FE chips

15. Stephan Haensel - LP Subsystems Meeting - DESY Modules HV Kapton Foil deliver the HV bias voltage to the sensor backplane isolate the sensor backplane from the carbon fibre profiles modified leftovers of the CMS sensor recuperation campaign are used  they contain already RC circuits to stabilize the HV line Wire Bonds standardised ultrasonic wire bonding with a Delvotec 6400 automatic bonding machine aluminium wires: 25 μm diameter including 1% silicon

16. Stephan Haensel - LP Subsystems Meeting - DESY Modules Carbon Fibre Beams backbone of each module consists of two carbon fibre T-beams for such a low quantity it’s not affordable to order perfect profiles from a company  SECAR Technologie GmbH provided rectangular beams  not maximised in terms of radiation length and rigidity  two such beams get glued together with a thin film of araldite glue to form a T-beam which is rigid enough to support the sensors, pitch adapter and the front-end hybrid

17. Stephan Haensel - LP Subsystems Meeting - DESY Moveable Support System two aluminium sliding carriages for the silicon modules get build by IEKP Karlsruhe –movement of the two diagonally arranged frames, containing the silicon modules, independently in both, phi and in z direction phi-direction: curved rails mounted at the outside of the magnet and at the beginning of the magnets bottleneck z-direction: the sledges move along two round rods via a threaded rod Rails

18. Stephan Haensel - LP Subsystems Meeting - DESY Cosmic Run design of the silicon envelope has to be changed:  modules will be installed at the top and bottom of the TPC which interferes with the support plates of the TPC  sliding carriage for the cosmic run silicon envelope only needs to be moveable in z-direction  no changes are needed on module level very rough estimation expects only about 20 Muon coincidences per day in the intersecting readout areas of all four silicon sensors  readout of 768 sensor strips lead to a small sensitive area of only 38,4 mm width per module

19. Stephan Haensel - LP Subsystems Meeting - DESY Done & To Do HPK sensors passed QA tests first prototype module was already build and shipped to IEKP Karlsruhe to make a prototype sliding carriage the needed space for the envelope has to be fixed in agreement with the TPC support structures  quite narrow in cosmic setup  ± no interference in test beam setup it has to be defined were the envelope support can be fixed  most probable at the outside of the magnet and the beginning of the magnets bottleneck via curved rails sliding carriage has to be build final modules have to be build  first intermediate PAs received but not tested  gluing and bonding jigs in progress readout system has to be fixed  CCUMs have to be found + new ICBs build  or emergency plan is needed (APV - ARCs, Beetle chip - ALIBAVA) readout software has to be determined and combined with TPC software

20. Stephan Haensel - LP Subsystems Meeting - DESY First Prototype broken CMS-R2 hybrids, dummy sensors and dummy intermediate pitch adapter, Stephan Haensel - LP Subsystems Meeting - DESY

21. BACKUP Slides

22. Stephan Haensel - LP Subsystems Meeting - DESY HPK Sensors (6 needed for this setup) -single-sided AC coupled SSD -Sensor size: 91,5 x 91,5 mm² (± 0,04 mm) -Wafer thickness: approx. 320 μm -Resistivity: such that depletion voltage: 50 V < V depl < 100 Volt -Leakage current: < 10 μA per sensor -Biasing scheme: poly-Silicon Resistor with 20 MW (± 5 MW) -Number of strips: 1792 (= 14 x 128) -Strip pitch: 50 μm pitch, no intermediate strips -Strip width: 12.5 μm -Dielectric Structure: Oxide (SiO2) + Nitride (Si3N4) between p+ and aluminium strips. (Thicknesses like for CMS) -2 bond pads on each side of the strip (CMS size) -1 probe pad on each side of the strip (contact to p+) Wafer Layout 91,5 x 91,5 mm