Phase2 Pixel Sensor: Meeting on

LHC CMSDetectorUpgrade

CMS Tracker Meeting 1

Phase2 Pixel Sensor: Meeting on

D. Bortoletto, Purdue University & University of Oxford

D. Bortoletto, May 20, 2014



Bump bonding for hybrid pixels remain a dominant cost for hybrid detector. The cost for a single detector unit have been over € 200 - 300

• Readout chip (ROC) : sensor chip (SC) : bump bonding (cost ratio) = 1:2:7!

• BB technology used in CERN pixel detectors is not commonly available in small volumes. Flip chip assembly part has caused the rise in total costs during last two years (pie diagrams).


Phase 2 Pixel Sensor Working group meeting

27%

32%

40%

Cost structure 2008 - bump bonding of single detector (estimate)

ROC bumping & dicing SC bumping & dicing Flip chip bonding

23%

27%

50%

Cost structure 2010 - bump bonding of single detector (estimate)

ROC bumping & dicing SC bumping & dicing Flip chip bonding

M. Campbel



In this meeting we would like to discuss with companies the challenges for Phase 2

The environment of HL-LHC:o Operations in 140 collisions per bunch crossing at 5x1034 cm-2 s-1

and 40 MHz o Maintain occupancy at ≈ % level

– Higher granularity / smaller pixel require smaller thinner pixels


Phase 2 Pixel Sensor Working group meeting



try


Pixel geometries

PIXEL SIZES under Consideration



What is the minimal bump bonding pitch and bump bonding pad size that can be achieved with your technology?

How large can the die be or bb density to achieve a good yield (similar to the one that was achieved by the current pixel sensors) ?

What is the minimum thickness of the ROC and sensor wafers that you can handle?

Are they any interesting development in BB that we should be aware of?

Any other issue that we should consider?D. Bortoletto, May 20, 2014

The questions

Documents

Phase2 Pixel Sensor: Meeting on