Origami Chip-on-Sensor Design:Progress
andNew Developments
19th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
TWEPP 2012, Oxford University
TWEPP 2012, C. Irmler (HEPHY Vienna)
Outline
• Introduction• Status• 2-DSSD Module• Cooling• Summary
219th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Motivation
• Belle II SVD ( M. Friedl)
• Super KEKB– 7 GeV e- on 4 GeV e+
– Center of mass energy: Y(4S) (10.58 GeV)
319th September 2012
~1 km in diameter
Super KEKB Belle II
Linac
About 60km northeast of Tokyo
• SVD Requirements:– Twice as large– Low material budget– Low occupancy– Fast readout (APV25)– High SNR– Chips closest to sensor
strips
Origami Chip-on-Sensor Concept
TWEPP 2012, C. Irmler (HEPHY Vienna)
The Origami Chip-on-Sensor Concept
419th September 2012
• CF reinforced ribs• 6” DSSD• 1mm Airex sheet• 3-layer polyimide PCB• Thinned APV25 • Connection to Strips:
– PA on top side– wrapped PA for bottom
• Single cooling pipe
• Trade-off between material budget & SNR
• 0.55 X0 (averaged)
a) Top view:
APV25 chips(thinned to 100µm)
3-layer kapton hybrid
fanout for n-side (z)DSSD
double-layer flex wrapped to p-side (r-phi)
cooling pipeCF sandwich ribs
side view(below)
b) Side view (cross section): APV25(thinned to 100µm)
CF sandwich ribs(mech. support)
cooling pipe
DSSDAirexKapton
wrappedflex fanout
n-side
p-side
TWEPP 2012, C. Irmler (HEPHY Vienna)
Belle II SVD
519th September 2012
APV25 chips
Cooling pipe
Origami ladder
Sensor underneath flex circuit
Pitch adapter bentaround sensor edge
End ring (support)
TWEPP 2012, C. Irmler (HEPHY Vienna)
Belle II SVD
• 4 layers of 6” DSSDs• Radii: 38/80/105/135 mm • 2/3/4/5 sensors per ladder• Origami PCBs in L4-6• L3 & edge sensors read out by
conventional hybrids• 3 different PCB designs
619th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Outline
• Introduction• Status• 2-DSSD Module• Cooling• Summary
719th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Origami PCBs
3 types of 3-layer Origami PCBs:– backward (-z), short tail– center (ce), for central sensor, long tail– forward (+z), routed along slanted sensor, complex shape
819th September 2012
-z
ce
+z
TWEPP 2012, C. Irmler (HEPHY Vienna)
Pitch Adapters
• All available in single- and double-layer designs
• PA0: short, n-side, glued onto Origami PCB
• PA1: first half of p-side strips
• PA2: second half of p-side strips
919th September 2012
Bond pads of single-layer PAs
TWEPP 2012, C. Irmler (HEPHY Vienna)
445 mm
125 mm
The Evolution of Origami Modules• 2008: Introduction of concept• 2009: Feasibility shown with 4” DSSD module• 2010: First full-size module with 6” DSSD• 2011: Re-design to fit mechanical requirements of Belle II
SVD ladders, beam test with CO2 cooling, …
1019th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
2012
• How to assemble ladder withtwo or more Origami PCBs?
• Not possible sensor by sensor• Combined procedure required• 2-DSSD Origami module
– 2 HPK DSSDs– Two types of Origami PCBs (-z and ce)– Single-layer PA0/PA1/PA2
1119th September 2012
2-DSSD Origami Module
TWEPP 2012, C. Irmler (HEPHY Vienna)
Outline
• Introduction• Status• 2-DSSD Module• Cooling• Summary
1219th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Assembly Location• Kavli IPMU
Institute for the Physics and Mathematics of the Universe
• Belongs to Tokyo University
• Kashiwanoha Campus• New clean room and lab
for L6 ladder assembly
1319th September 2012
~30km north of Tokyo
TWEPP 2012, C. Irmler (HEPHY Vienna)
Team
K. Kamesh (TIFR), C. Irmler (HEPHY), Y. Onuki (Tokyo U.), K. Negishi (Tohoku U.)
1419th September 2012
E. Kato(Tohoku U.)
N. Shimizu(Tokyo U.)
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching of PA1 & PA2
1519th September 2012
• Almost unchanged procedure• PAs were aligned to sensor and
then picked up with a vacuum jig• New: mask to apply glue• Ensures uniform thickness• Future: cutting plotter
mask samples
Graphtec CE5000-60
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching Origami PCBs• Wire bonding p-side• Placing sensors onto an
assembly bench• Optical alignment
(not done this time)• Attaching Airex sheets
(in future: 1 per ladder)• Glue Origami PCBs
– pre-assembled APV chips– first CE – then –z
• Wire bonding n-side
1619th September 2012
-zCE
TWEPP 2012, C. Irmler (HEPHY Vienna)
Bend and Glue PA1, PA2
1719th September 2012
• Already established procedure
• Micro positioner with vacuum head
• Masks to dispense glue• Pre-bend PA and align
vacuum head• Align PA to APV and
lower down• Glue curing• Followed by ~2500 wire
bonds
TWEPP 2012, C. Irmler (HEPHY Vienna)
Final Module in Frame
1819th September 2012
Top and bottom views (w/o cooling pipe)
TWEPP 2012, C. Irmler (HEPHY Vienna)
Outline
• Introduction• Status• 2-DSSD Module• Cooling• Summary
1919th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Cooling Pipe
2019th September 2012
Cooling pipe
• Single cooling pipe forseveral ladders– Little space for connections– Outer 1.6 mm
• Custom fixture to hold the pipe
TWEPP 2012, C. Irmler (HEPHY Vienna)
Cooling Contact – Pipe on APV25 Chips
Requirements:• Re-mountable cooling coil (no glue …)• Easy and safe mounting (bond wires …)• Electrically isolating• Radiation hard material• Avoid stress at sensor• Efficient heat transfer
– large contact area– adjust height differences of APVs– thermally conductive gap pads
2119th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Thermal simulationsThermally conductive Gap Pads
• Heatload/APV: 0.35W• Coolant temperature: -20°C• Tube: stainless steel AISI 316L, wall 50μm• Gap pad: 86/125 Keratherm
• λ [W/mK]: 1.5W/mK• Very soft, 1mm thick• Radiation hardness? Will be tested in October
19th September 2012 22
TWEPP 2012, C. Irmler (HEPHY Vienna)
Pipe Fixture – First Concepts• Prototype 'big' screw clamp • One part clamp
Screws Too bulkyStructure is fragileand the contactsurface is small
Large force necessary to snap tube intothe clamp
19th September 2012 23
TWEPP 2012, C. Irmler (HEPHY Vienna)
Pipe Fixture – Improved Design
Hinge clamp:• PEEK G450• micro water jet cutting
– fabrication tolerance: 0.01mm– Max. wall thickness: 20mm– Min. inner radius:
0.1mm
• Disadvantage: 2 parts• First prototypes delivered• Used on 2-DSSD module
19th September 2012 24
TWEPP 2012, C. Irmler (HEPHY Vienna)
Cooling Pipe Mounting• Clamp bases glued
onto Origami PCB• Keratherm strips
placed onto APV chips
• Pipe put into camp bases
• Clamps closed
2519th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Final Module with Cooling Pipe
2619th September 2012
27TWEPP 2012, C. Irmler (HEPHY Vienna)
Performance of CO2 Cooling
•Three 6” Origami modules were tested in a 120 GeV beam (October 2011)•Stable operation of CO2 cooling system for 3 days•The sum of bias currents of sensors decreases from >70µA to ~20µA
19th September 2012
0 1000 2000 3000 4000 5000 6000 70000
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
time [s]
bias
cur
rent
[nA]
Bias current of all 3 modules vs. time
CO2 systemoff CO2 system on
24h4h
Pressure reduction for lower temperature
TWEPP 2012, C. Irmler (HEPHY Vienna)
2-DSSD Origami Module Performance
• A week ago: first source test of new module with CO2 cooling• So far the module works well • Ready for beam test in October
2819th September 2012
preliminary
TWEPP 2012, C. Irmler (HEPHY Vienna)
Outline
• Introduction• Status• 2-DSSD Module• Cooling• Summary
2919th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Summary• Origami chip-on-sensor concept adapted to fit
requirements of Belle II SVD ladders– 6” sensor, three flex designs
• Assembly procedure extension to full ladder– in progress
• Design and first prototypes of pipe fixture• Recently assembled a 2-DSSD Origami module• Beam test and irradiation in October 2012• Start of ladder production scheduled for
summer 2013!
3019th September 2012
31TWEPP 2012, C. Irmler (HEPHY Vienna)
Thank You
19th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Spare Slides
3219th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Improved Version of One Part Clamp
3319th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching Airex
• We used one piece per sensor• Later we will use a single sheet per ladder
3419th September 2012
12
3 4
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching Origami hybrids
1. Aligned CE to sensor2. Lifted it with Origami jig3. Applied glue4. Put back onto assembly bench5. Waited until glue has been cured6. Removed Origami jig7. Aligned –z to sensor8. Repeated from step 2.
3519th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching Origami hybrids
3619th September 2012
1 2
3
4 & 5
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching Origami CE
3719th September 2012
1 2
3
4
5
TWEPP 2012, C. Irmler (HEPHY Vienna)
Attaching Origami -z
3819th September 2012
TWEPP 2012, C. Irmler (HEPHY Vienna)
Bend and Glue PA1, PA2 – Apply Mask
3919th September 2012
4: flatten glue
2
3: dispense glue
1: apply mask
5: remove mask
TWEPP 2012, C. Irmler (HEPHY Vienna)
Pre-bend and attach stopper
4019th September 2012
Stopper for PAs
pre-bended PA
6
align vacuum head to assembly bench and PA
design concept of PA stopper
TWEPP 2012, C. Irmler (HEPHY Vienna)
Align PA to APV chips
4119th September 2012
7: PA to APVs
8: lower down9: cure glue
Bond pads visible
Thermally conductive Gap Pad• Responsible for Origami cooling: Annekatrin Frankenberger • Selection of thermally conductive materials with different properties.
42TWEPP 2012, C. Irmler (HEPHY Vienna)19th September 2012
86/125Keratherm
2000S40Bergquist
575-NS Parker Chomerics
Sil Pad 800Bergquist
λ [W/m K] 1.5 2.0 1.2 1.6Hardness [Shore 00] 10 30 70 Shore A 91
Thickness [mm] 0.5 - 5 0.5 – 3.1 0.5 – 2.5 0.1Silicone x x -- xRadiation hardness ? ? ? x
Gamma irradiation tests (@ Mol in October)
TWEPP 2012, C. Irmler (HEPHY Vienna)
Thermal simulationsThermally conductive Gap Pads
• Heatload/APV: 0.35W• Coolant temperature: -20°C• Tube: stainless steel AISI 316L, wall 50μm• Gap pad: Sil Pad 800 Bergquist
• λ [W/mK]: 1.6W/mK• Hardness Shore A: 91• Thickness: 0.1mm
good contact? Adjusting unevennes?
19th September 2012 43
TWEPP 2012, C. Irmler (HEPHY Vienna)
Tube fixtureDisplacement simulation
Necessary displacement UX = -0.4mm
Acting force 1.4N
19th September 2012 44