Minutes of CMS Tracker week (1/28/03-2/1/03)

Electronics testing during module production

  • TOB Hybrids are produced by Cicorel, where they go through a quick functionality test – FHIT, which lasts ~ 1 min.
  • Hybrids are delivered to Strasbourg and sent to CERN.
  • At CERN hybrids are tested by FHIT upon arrival. Pitch adapters are gluoned on hybrids. About 50% of the devices are bonded at CERN. Bonded hybrids are thermo cycled using ARC test and sent to FNAL.
  • Unbonded hybrids are sent to UCSB where they are bonded and thermocycled using ARC test. In the future this step will be eliminated and bonding Hy to PA will be done during module bonding.
  • AI[1]: need equipment for thermo cycling, pulsing – to be sent to UCSB by Alan Honma.
  • Bonded hybrids are used to construct modules.
  • During module bonding known pinholes are skipped in automatic procedure.
  • After a module is bonded it undergoes an ARC based LED test to identify any additional pinholes.
  • Then a module undergoes a long term test using Viennacold box.
  • AI: It is essential that a Vienna cold box be delivered to UCSB for reworking to start the module production. This cold box is then sent to FNAL.
  • AI: Parts for another cold box have to be sent to UCSB to construct a cold box to be used for module testing at UCSB.
  • AI: It is essential that the multimodule software be available for the beginning of module production, otherwise the throughput is limited to 20 modules per month.
  • A module is LED tested once again to check for pinholes that develop during burn in.

Electronics testing during rod production

  • Opto-hybrids are produced by Kapsch, where they go through a quick functionality test, which lasts ~ 1 min.
  • Optohybrids are delivered to Vienna and sent to CERN.
  • AI: It is desirable to reliably establish an infant mortality rate of opto electronics. Present low statistics data (1 laser diode out of a 100 failing) suggest unacceptably high rate for rod reworking - ~16%, which is a time consuming procedure. Optohybrids must undergo a burn in testing preferably in Vienna or at CERN.
  • At CERN optohybrids are mounted on rods and cabled.
  • Cabled rod undergoes a functionality test which lasts ~5 min, but could be extended to several hours, which is desirable.
  • A cabled rod is sent to FNAL or UCSB, where upon arrival it is tested using exactly the same procedure as at CERN before shipping.
  • Modules are mounted on rod.
  • Rod is burned in for 3 days. US CMS silicon group will use whatever software is available at the moment when rod production begins.
  • AI: It is possible to run slow control on a separate PC with little or no communication with DAQ PC. TEC petal integration group claims that this software is available at the moment. Contact Vincent Lemaitre for information.
  • Before shipment to CERN rods are tested on a quick test – presumably the same that was used upon receiving.
  • US group views it as essential that upon arrival at CERN rods are tested using the same test configuration as before shipping.
  • Then, rods are tested on x-y table.

[1] Action item