Tracker Status

September 17, 2004


Tray Assembly

-        Work progressed on improving the Plyform facilities and procedures per the ART report.

-        Tungsten tiles were etched and primed in both the USA and Italy.  The Italian company doing the etching found that they had to remove a lot of material (6 microns) from the thin (rolled tungsten) tiles to find pristine metal, so that is a good indication of what was causing bonding problems and why the thick tungsten tiles worked so much better than the thin (the thick tiles were sintered tungsten and were precision ground to the desired thickness).

-        Some first coupon peel tests were executed at GSFC.  The results so far are hard to interpret, so they are repeating the test with unprimed tungsten for comparison.  The first peel tests in Italy should be done Monday.

-        Production of bare trays progressed at Plyform.

-        A problem was found with the new fixtures for bonding MCMs to the tray closeouts.  In some circumstances it can result in one of the MCM connectors interfering slightly (up to 0.2mm) with the tower sidewall.  This is being studied on all the existing trays, and the fixtures or procedures will be corrected in time for the next assemblies.



-        Production and testing is continuing at Teledyne and SLAC.  Teledyne has implemented all the process changes needed to resolve the conformal coating workmanship issues, and a shipment of MCMs with those changes was received at SLAC this week.

-        The latest burn-in of 36 MCMs completed, and tests of clock-duty-factor margins were carried out on that stack.  Those results are being summarized in order to work toward closure of NCR 107.

-        Work progress on the final report on MCM/ASIC qualification testing.

-        Several non-flight MCMs are undergoing 200 thermal cycles to investigate the effects on pitch adapters and conformal coating.

-        A lot of effort went into resolving the pitch-adapter trace cracking issue.  Two different prototypes were started in parallel to try to make non-cracking pitch adapters, and work started in earnest to do detailed design on a fixture to test electrically the pitch adapters on all MCMs, for final screening.

-        More Tracker manpower was dedicated to the endless meetings on conformal coating workmanship.


Flex Circuit Cables

-        The 3rd party lab concluded that the GSFC coupon test results were correct.  Parlex completed cause and corrective action regarding the coupon failures.

-        A new procedure was released for testing of the flight cables using MCMs, prior to tower assembly.


Tower Assembly

-        The trial assembly of a tower did not start this week, because of a storm-related power outage in Pisa that knocked out the clean-room air conditioning and because of the work needed to study the MCM connector interference issue.  The air conditioning is back online as of yesterday.