1. Pixel Demonstrator Programme
D. Álvarez Feito1; M. Hamer2 ;S. Kuehn3; S. Michal4;
1CERN EP-DT; 2University of Bonn; 3CERN EP-ADE; 4Université de Genève;
CERN, May 2017
15/05/2017

2. Why a Pixel Inclined Layout?
Flat section + Tilted region:
Reduction in silicon area for large η coverage
Lower heat load
Less services
Cost reduction
Joint effort over the last two and a half years to demonstrate physics advantages (LTF) and feasibility of mechanics/cooling (UniGe & CERN)
Pixel Barrel

3. SLIM v1 Concept Support Structure: TRUSS Longeron
Support modules from two adjacent layers
Two types to couple 3 and 4 CLs
Thermal management: Module Cells
Cooling block (Al-Cf) + TPG Plate
Two types: Flat (M4) and Tilted (M2)
Alignment Pins
TPG Plate
Phase-change TIM
Base Block
Solder layer
Cooling Block
Titanium pipe

4. Modules and Module Cells
Two types of modules and module cells:
Tilted (or inclined) Cell: M2 or DUAL modules (~40x20mm)
Flat (or barrel) Cell: M4 or QUAD modules (~40x40mm)
~40mm
~20mm
Tilted cell
~40mm
~40mm
Flat cell

5. SLIM v1 Pre-qualification
Several longeron prototypes (~1m long) tested for FEA validation
A number of single cells and “triplets” have been manufactured and tested, obtaining positive TFM results
TRUSS Longeron
(“hybrid” construction)
See S.Michal talk at Valencia ITK Week:

6. Parallel R&D: SLIM v3 Concept
Different cooling solution: the “curly” pipe
Alternative to blocks to cool inclined QUADs (~40x40mm)
J.BENDOTTI
J.DEGRANGE
F.PEREZ
M.VERGAIN
N.DIXON; R.GOMEZ
In Construction
Preliminary Results
Global TFM (˚C∙cm2∙W-1)
Inclined region
(8 loops)
Flat region
Inclined region
(8 loops)

7. Stave Demonstrator

8. 2017 Demonstrator Programme: Objectives
Build & test large scale, realistic prototypes
(Aimed at Pixel TDR – End of 2017)
Validate SLIM local support concept → Engineering Prototypes
Thermo-Fluidic prototypes
Thermal prototypes
Thermo-mechanical prototypes
Material qualification (i.e. irradiation campaign)
Validate integration and electrical services schemes
Short electrical prototypes
FINAL STAVE DEMONSTRATOR
Validate procedure for loading, re-workability and survey
Loading prototypes

9. Final Stave Demonstrator (the final goal)
Layer 2-3 Longeron, 4CLs (SLIM Layout)
See EMDS ( ) for envelope CAD model
1600mm
1 CL loaded with electrical modules
3 CLs loaded with silicon heaters with embedded RTDs
Modules and heaters connected to real stave services (flexes)
Local Support
Length (m)
Layer
# Modules per CL
Module Type
Power Dissipation per CL (W)
Cooling Power Required (W)
L23
Rectangular Longeron (i.e. 4CLs)
1.6 2
Flat 12 M4
302.4
1276.8
Tilted 30 M2 3 14
336.0 32

10. Short Electrical Prototypes
Needed by 4 institutes to perform further electrical tests in the future (Wuppertal, Bonn, UniGe, CERN)
Each prototype comprises:
Support structure with 1 CL (L3_C_X+)
7 flat cells loaded with electrical modules (QUADs, B1 to B7)
Stave flex (L3_C_X+_BSF)

11. Engineering Prototypes

12. Demonstrator Programme: Engineering Prototypes
Full length supports structures and prototypes to be tested
Thermo-fluidic prototype (under construction)
Thermal Prototype (single CL populated with cells and silicon heaters)
Thermo-mechanical Prototype (1/2 longeron with 4CLs and base blocks)
Simplified test to assess the variability of HTC along the pipe for different heat loads and phi orientations (heat applied locally using braced copper blocks and kapton heaters)
Block geometry selected to replicate heat flux at the pipe surface
Assess TFM changes along the pipe & qualify the production performance
Dedicated thermal flexes
Tested in a cold box to validate FEA (modules simulated with bare silicon)
Services and cells added in steps
End-of-longeron supports and End-flanges also to be prototyped

13. Demonstrator Programme: Thermo-Fluidic Prototype
Simplified test to assess Variability of HTC along the pipe for different heat loads and phi orientations (& validate COBRA simulations)
Realistic pipe length (1.6m)
Heat load applied locally
Braced cooper blocks with glued kapton heaters
NTCs glued at each block
To be tested in B186 (TIF Cooling Plant)
Block geometry selected to replicate heat flux at the pipe surface

14. Thermal Prototypes
Small scale thermal prototype (limited by available cooling power)
4 flat & 4 tilted cells loaded with silicon heaters and glued thermal sensors
Heater powering and sensor RO via cables
TFM measurements for different vapour qualities
“Curly” pipe triplet with inclined QUADS
Large scale thermal prototype
1 full CL or 2 x ½ CLs + U turn
Cells loaded with silicon heaters with embedded RTDs (and heater flexes)
Thermal flexes used to power the heaters and read the PTs
Assess TFM changes along the pipe & qualify the production performance
The support structure doesn’t need to be realistic
Dedicated thermal flexes
(produced before the real stave flexes)

15. Thermo-mechanical Prototypes
Cold box testing CPPM) to validate FEA models
Modules simulate with bare silicon dummies (No CO2; No heaters!)
Single cell testing → Assess deformation at the module level
Large scale thermo-mechanical prototype tested in steps
1 or ½ longeron with 4CLs and base blocks
Added 4 thermal flexes to simulate stave services
Added a reduced number of cells loaded with silicon dummies and fake module flexes connected to the thermal flexes
Short prototype of SLIM v3
Support structure (~400mm) + local supports + “curly” pipes
Cells with silicon dummies (no flexes needed at first)

16. Material Characterisation & Irradiation Campaign
Irradiation campaign to study various glues and resins
Lap joint samples
Material tests before and after irradiation to assess potential damage
Apparent thermal conductivity (B154)
Mechanical strength (tensile testing machine)

17. We are not alone…
Up to 15 institutes take part in the demonstrator programme:

18. What are we (i.e. DT/CERN) supposed to do?

19. Proposed Integration Scheme
Functional Longeron
(including pipes and base blocks)
Module
(& Heater) Flexes
Stave Services
(i.e. stave flex)
Bare Cells
Modules
(& Heaters)
Off-stave services
(e.g. powering, readout, cooling, DSC, cable saver board…)
PSPP assembly & QA
Bare cell QA
(thermal performance)
Flex Integration
Module (& Heater) Assembly & QA
Longeron ready to “receive” modules
Module Loading
Loaded Cells
Electrical (& T) QA
Longeron Integration
(+ Module flex connection to stave flex)
Demonstrator
Connection to setup for system tests

20. Functional Longeron TRUSS longeron manufactured in several parts
2 x TRUSS + central sandwich step
Local CFRP supports
2 x End-of-longeron supports
Bonded on alignment jig
Bending of the titanium pipes (ahead of Ni coating)

21. Functional Longeron UniGe to solder base blocks to Ti pipes
Jig in production
Once the solder is completed, the plan is to use the same jig to glue the pipes to the local CFRP supports and the TRUSS (DT & UniGe).
Ideally, we would use the same jig to glue the end-of-longeron supports using the same jig (same reference used to position the blocks).

22. Module Cells Inclined Cells Flat Cells
UniGe to design & produce tooling for assembly of module cells
Not clear yet whether we need to help with the cell production (~350 cells to be produced)
Inclined Cells
Flat Cells

23. Silicon Heaters with Embedded RTDs
CERN to produce silicon heaters with embedded RTDs
Minimum of 5 PTs per heater
Order placed with external supplier (VTT)
M2 & M4 heater flexes compatible with the new silicon heaters to be designed and produced by CERN

24. Heaters (& Module) Assembly + Calibration
Design and production of tooling for heater (and module) assembly
Gluing of flex to heater + wire-bonding
Initial design for M4s already prepared by C. Bault (needs to be adapted to new dimensions). Produced externally.
Module Alignment Jig
Vacuum Pickup Chuck
Flex Alignment & Gluing Jig
Heater Test Bench & Database
Design & Production of PCB to calibrate several heaters simultaneously
Setup and maintain database to store & trace calibration results (RTD’s curves and heater resistance)
Tooling design (after debugging) to be shared with other institutes (LPHNE, Bonn, LPSC) so that they contribute to the heater assembly/calibration.

25. Heater Loading Loading of the heaters on the bare cells
Bare Module Cells
Loading
Loaded Cell
Heater Assembly
Current idea is to incorporate the loading functionality to the cell assembly jigs so that multiple heaters can be loaded in a single step (Alignment based on silicon edges + pins)

26. Integration will be carried out at CERN (in B154)
Longeron Integration
Integrating the stave services inside the functional longeron (help from LAPP)
Mount the functional longeron on the handling frame
The attachment of the structure to the handling frame will mimic the support conditions in the real detector (i.e. replica of end-flanges at both ends)
The demonstrator will remain on this frame for the entire lifecycle (integration, survey, transport and system testing)
Gluing the cells (with heaters/modules) on the functional longeron and connection to the services
Integration will be carried out at CERN (in B154)
Handling frame to be designed and produced at CPPM (to match our end-of-longeron supports)

27. Testing under vacuum and with dry air flow
Thermal Setup (B154)
Update thermal setup in B154 to test
Short thermal prototype
Long thermal prototype
Testing under vacuum and with dry air flow
Required modifications:
New flanges compatible with new PCB for thermal flexes
Commissioning of the cartridge heater for control of vapour quality
Currently discussing whether the vacuum vessel will be extended in length
Updated TRACI to allow testing with higher mass flow rates
New thermal readout for the new silicon heaters and CO2 pressure & temperature sensors
Power supplies and control for the silicon heaters and cartridge heaters
Power/Cooling interlock system

28. System Setup (SR1)
New setup built in SR1 to perform system test with the demonstrator:
Test chamber (light-tight)
Feedthroughs
Environmental control (e.g. humidity, dry air)
Cooling (updated SR1 plant) + thermal readout (~1000 sensors)
Support for the demonstrator handling frame and CSBs
Source stage, linear movement and control
Camera system
~4m

29. Proposed Organisation (Who is doing what?)
Support Structures
(TRUSS, local CFRP supports, end-of-longeron supports, pipe bending, gluing)
Heater & Module Assembly
(heater design, heater flexes, heater assembly including tooling, calibration and database)
Loading & Integration
(cell loading, assembly of long thermal prototype, thermo-mechanical prototype & demonstrator)
Thermal Setup
(Vessel + Flanges, piping, connection PCB, readout, commissioning)
Thermal Testing
(short and long prototypes)
System Test Setup
(design and construction of environmental chamber, control & interlock, source stage, cooling piping, thermal readout)
Material testing (irradiation, thermal, mechanical)
Valery
Nicola
Neil
Francois
Kari
Francisco
Ruben
Xavier
Maurice
Jerome
Jordan

30. First/Ongoing Activities
Who
Task
Completion date
Jordan
Design of end-of-longeron supports. Design of pipe bending jig
24/05/2017
Edyta
Final Design of moulds for local supports
19/05/2017
Ruben
Testing lap joints for glue selection. Design of upgraded thermal setup.
Kari
Design of heater assembly tooling
02/06/2017
Neil
Dismantle SR1 setup. Assemble thermo-fluidic prototype
30/05/2017
Francois
Produce initial lap joints. Produce central sandwich.
26/05/2017
Francisco
Design of end-of-longeron supports. Produce curly pipe triplet.
Jerome
Production of local support moulds
Maurice
Finish 3PB jig. Production of pipe bending jig
Nicola
Design of heater flexes (M2 & M4)
Valery
Produce first complete 0.8m long TRUSS.
Xavier
Develop readout and PCB for thermal setup
30/06/2017

31. Final Comments Detailed plan available Weekly progress meetings
Please, could you let me know when you are planning to go on summer holidays to take it into account in the planning?
Weekly progress meetings
Mondays from or Tuesdays from to 12.00?

32. Questions?

33. Additional Material

34. Layer_Side_Flank_Item&Number
Nomenclature
Unified nomenclature (following ATLAS axis convention) now summarised in EDMS / Sharepoint
Numbering of the individual modules included
Layer_Side_Flank_Item&Number
S. Michal
CL=cooling line
BM=Barrel Module
IC=Inclined Module
BSF=Barrel Stave Flex
ICF=Inclined Stave Flex
………. 2 3 A C
X+X-

35. Numbering to be also used in DCS
Nomenclature
Unified nomenclature (following ATLAS axis convention) now summarised in EDMS / Sharepoint
Numbering of the individual modules included
Numbering to be also used in DCS
S. Michal

36. Loading Prototypes
Small scale prototypes to validate cell loading and longeron integration procedures
Module loading on SLIM cells (i.e. module/cell loading)
Integration of cells on functional longeron (i.e. longeron integration)
Re-work/Replace defective cells
Survey of the final assembly
Electrical and/or thermal tests to be performed between sub-steps to ensure that the procedures do not impact the performance.

37. Prototypes: Summary Thermal Thermo-mechanical Electrical
#CL
#Cells per CL
Longeron (mm)
Heaters
Modules
Flat
Tilted
Thermal
Short 1 4 -
Silicon heaters with glued RTDs
Large Scale
(or 2 x ½) 14 32
1600
(not required)
Silicon heaters with embedded RTDs + heater flexes
Thermo-mechanical
Single cells
Bare silicon dummies
Large scale (v1)
L2: 6
L3: 7
L2: 15
L3: 16
800
Bare silicon dummies with fake module flexes and connectors
Medium scale (v3) 2
Electrical
Short electrical 7
M4: 7
Final Demonstrator
L2: 12
L3: 14
L2: 30
L3: 32
Silicon heaters with embedded RTDs + heater flexes in 3CLs
M4: 14
M2: 32