Re: tasks to get ready for Dec review

["Craig Ogilvie" <cogilvie@iastate.edu>]

Bump-Bonding/Thinning Si Hybrid Pixels: Questions/Answers for R&D Review

1) Current range of technical options

There are several current efforts in the HEP community on R&D on
bump-bonding and thinning Si hybrid pixels. Our overall plan is to join with
two efforts, one at FNAL (PHENIX effort led by ISU) and the other at CERN
(PHENIX effort led by RIKEN). By participating in ongoing work we move
quickly up the learning curve and leverage the investment made by HEP.

Separately there are many commercial technologies that either bump or thin
Si wafers. The requirement of having bumped/thinned hybrids narrows the list
of vendors as does the fine pitch of ~50microns. Here are the leading
vendors
· McNC North Carolina/Unitive (FNAL-led effort): Process is bump first then
thin. Problems with the bumps/wafers are occurring in the thinning step.
Uses solder bumps
· AIT Hong-Kong thins the wafers first then bumps. Success with 150 micron
 4" wafers. (FNAL led effort). Uses either indium or solder bumps.
· IZM Berlin (CERN led effort). Will do large fraction of bumps for ATLAS
with thinned detectors down to 200 micron
· VTT Finland (CERN led effort). Plans to do large fraction of bumps for
ALICE with thinned detectors down to 200 micron

2) What needs to be done to evaluate/test these options

Participate in R&D work at FNAL and CERN. R&D funded post-doc would be at
FNAL for a few months during 2003 to help evaluate bump-bonding samples sent
by McNC and AIT. This will help develop PHENIX expertise as well as help
evaluate two of the four possible vendors (especially for 8" wafers). Later
as this participation evolves some PHENIX readout chips and sensors may be
thinned and bumped and then tested at FNAL. RIKEN is participating in ALICE
so is in contact with their R&D program.

3)  Schedule/Manpower

FY03
a) Have post-doc work at FNAL for few months to gain experience in use
bump-bonding/thinning.

Manpower
0.5 FTE at post-doc level

FY04
a) trial PHENIX bump-bonding of prototype sensor and readout chip own
chip-set in 2004

Manpower
0.5 FTE at post-doc level

Milestones

· End-of-FY03 Decide which vendors to send trial wafers for thinning/bumping
· End-of-FY04 Validate vendors for thinning/bumping

Anticipated Weak Points (skeleton of answers)

· What are the criteria for validation of vendors ( contact at least xx% of
bumps, performance of sensor and readout-chip similar after thinning as
before thinning )
· What final thickness is required for the physics (need to go back over
previous simulations and spreadsheets that had multiple scattering versus
thickness)

----- Original Message -----
From: "Craig Ogilvie" <cogilvie@iastate.edu>
To: <phenix-silicon-l@bnl.gov>
Sent: Monday, November 11, 2002 10:37 AM
Subject: tasks to get ready for Dec review


> As we discussed at out last meeting, there are several tasks that we need
to
> get done to be ready for the Dec review of the R&D proposal. I put these
> down here with names attached. Could each of the people listed below send
> answers to these questions tot he list before Thursday 21 November? Then
we
> will discuss these at a phone meeting and Yuji and I will try to compile
> them for the Dec internal LOI
>
> Thanks
>
> Craig
>
> Physics Questions: Expanded from R&D and technical note
>     Spin (Yuji)
>         what is the x-range with proposed acceptance/channels
>         what rates, statistics, sensitivity do we expect for these
channels
>     HI
>         confirm y-range, pt range for open charm, open beauty in endcaps
and
> barrel
>         rates, pt range reached,  (Vladimir, Pat)
>         B => displaced J/psi => electron (Vladimir)
>
> Technical Topics
>     For each of the six separate R&D items, could the people listed below
> please answer the following questions
>
>         1) what is the current range of technical options, what tests have
> we started
>         2) what needs to be done to evaluate/develop/test these options
>         3) what is the schedule/manpower needed for these tests
>         4) what are the future milestones/decision points
>         5) what weak points are there that a reviewer would likely note
>         6) any other specific concerns.
>
> The separate sections are
>     a) Si strip readout, interface with PHENIX (Vince, Ken)
>     b) Hybrid Pixel readout, interface with PHENIX  (Axel)
>     c) Thinning/Bump bonding (Craig)
>     d) Endcap hybrids (David)
>     e) Monolithic (Craig)
>     f) Support Frame (David)
>
>
> ***************************************************************
> Craig Ogilvie cogilvie@iastate.edu
> A413 Physics (515)294-2219
> Iowa State University
> www.public.iastate.edu/~cogilvie/homepage.html
> Ames, IA 50011
>
>
>
>
>