Tracker Status

January 14, 2005


Tower A:

- Tower A is arriving at SFO this afternoon.

- Plans are in place to unpack it and install it into the cleanroom Saturday.

- Electrical testing and cosmic ray data taking will occupy Sunday and Monday. 

- The CMM at SLAC will be used to recheck the alignment next week.

- Then the tower top will get taped with aluminum for EMI shielding, and the EMI/EMC tests will be done.


Tower B:

- The tower is assembled, tested, packed, and on its way to Alenia for environmental testing.

- Vibration testing will commence on Monday.  The TRR was held this morning.


Sidewall Production

- The Tower-1 sidewalls have been laid up and are ready for machining.


Tray Assembly:

- All parts for Tower-1 tray assembly are at G&A and were inspected this week.

- SSD wafers were selected for heavy tray ladders to be assembled without encapsulation.  Such ladders will be used on all heavy trays and bottom trays from Tower 1 onward to avoid the issues with encapsulation delamination and wire bond breaking on the ladders.



- A lot of work was done this week to understand the issue with pitch-adapter trace cracking.

- The board radii were measured in detail and ruled out as being the issue.

- A fixture was built to study bending of pitch adapters over a 1-mm radius with controlled tension.  We found that with less than 5 lbs tension there is no cracking at all when the pitch adapter is bent around the radius.  9 lbs is required to cause traces to crack open and become non-conductive.

- The Teledyne fixture design was studied and understood to apply an uncontrolled and potentially high tension to the pitch adapter. 

- Richard Gobin is at Teledyne today working with them to try to adjust the fixture such that it works at least as well as it used to.

- An engineer is working to turn the G&A pitch-adapter bonding fixture into something that could be used in production, with the hope of restarting production next week.

- Parts were prepared to make a test of pitch-adapter bonding using the G&A prototype tool with pitch-adapters from the existing stock.

- Getting MCM production back on track is schedule critical, as the existing stock of MCMs can only equip about 5.5 flight towers.

- The low yield to date requires us to order more MCM parts, including more front-end ASIC wafers.  Those requisitions are in progress.



- 8 “cables” made especially (and economically) for stacked tray testing are almost ready to ship from SLAC to Pisa (1 more is already in Pisa).  11 more unassembled boards are also in hand.

- 8 more reject Parlex cables (which work fine, anyway) will also be sent for stacked tray testing.

- The Parlex process has been shown to be greatly improved by inclusion of the water-blast cleaning of the drill holes.

- SLAC conducted another thermal cycle test on 4 Parlex cables with *bad* coupons.  All survived with complete functionality 100 cycles that exceed the Tracker qual range.

- Parlex production will give us 2 to 4 of each cable type by the end of this month.   In addition, more than 4 of each type are in process.