CMS Tracker Week, CERN, July July 2003Tracker Week - Module ProductionSalvatore Costa - Catania Executive summary from Bonding WG Meeting 15 July 2003 Salvatore Costa INFN Catania

17 July 2003Tracker Week - Module Production2 Salvatore Costa - Catania News New Coordinator Alan Honma  Salvatore Costa I take up administrative tasks Alan stays on as Technical Advisor New Center Hamburg

17 July 2003Tracker Week - Module Production3 Salvatore Costa - Catania Center activity updates/problem reports CenterActivities/Problems AachenVibration test on a R6 TEC Module  broken bonds as in US TOB Modules BariBonding 1 st “real-final” Mod, found problems at PA ends, not supported by spacer (Suggested solution  equip jig w/ extensions to slide under PA opposite edges) Catania1 machine out of 2 stopped working: looking into problem FermilabAcquired 3 rd machine dedicated to CMS. Previous problems bonding on TOB Pas solved by cleaning residues from pads, with alcohol and swabs FirenzeAlso difficulties bonding at PA ends (see Bari) PisaPull & Electrical Test results on Sensor Test Structures (see) Santa BarbaraBonded 19 TOB mod before machine had hw problem (fixed). Pad cleaning w/ citric acid solution, a technique Alan fears is dangerous long-term StrasbourgObserved bond lift-offs, due to jig vibrations. Done + Pull Test on Test Structures TorinoPull study of Bond Force vs. U/S Power on RMT Pas (see) ViennaBonded w/ no problems 1 “real-final” TEC module out of 4 recently received ZurichPull Tests on recently delivered PAs: excellent results on all 3 batches, including the one declared unbondable at other Centers. Bonded first alignment module.

17 July 2003Tracker Week - Module Production4 Salvatore Costa - Catania Bonding-DB Usage Statistics I/F (v.2.0) installed: Catania 4/14 –Locally (out-of-the-box) 6/14 –Locally (with mods) 2/14 _________________________ CENTERS OK: 12/14 –No info 2/14 DB-ok Modules bonded: –Yes 7/14 –don’t know 4/14 –No 3/14 Data in DB from 5 centers (19 Modules) Change to Bonding-DB I/F: remove requirement of Sensor data in DB

17 July 2003Tracker Week - Module Production5 Salvatore Costa - Catania PA Bonding Problems In recent bonding tests of the RMT pitch adapters, Alan encountered –batches that fail the bonding tests AND –batches with significant large variations in bonding quality (from PA to PA and even within a PA) such that there were both passing and failing tests within the same batch. This means a sample test of a batch is not sufficient to identify problematic batches (which is what they have been doing so far). “I am no longer confident that those batches that "passed" in our single sample tests are necessarily good”. However, the Zurich Delvotec 6300 bonding machines which are at CERN Prevessin could easily bond every PA with no problems using their standard parameters. Then Alan was able, after a lot of searching, to find a set of bonding parameters which yielded good enough results to pass the bond pull tests. However, these parameters are very far from standard set and it is not clear if they are really safe ones to use in the long term. 5

17 July 2003Tracker Week - Module Production6 Salvatore Costa - Catania Attacking the problem Difference in bondability between CERN and Zurich machines might be due to the frequency of the ultrasonic generator. –Zurich Delvotec 6300's: 60KHz –CERN Delvotec 6400's (as well as all other 6400's in CMS): 100KHz Small batches of RMT PAs sent out/distributed yesterday to some centers, to extensively test them on individual machines –pull test w/ “standard parameters” –search of “optimal parameters’ –correlate w/ machine frequency Possible replacement of ultrasonic generator (and in some cases also transducer) in “faster” machines is being considered. (Cost ~15 kCHF)

17 July 2003Tracker Week - Module Production7 Salvatore Costa - Catania Changes to Bonding Procedure PA problems call for more extensive bond pull testing. Existing procedure already calls only for ~10 test bonds on every PA prior to regular bonding, but it is not really ‘enforced’ in that results are not to be recorded into DB:  Add bond test data on PA to Bonding Tables in DB  Include destructive bond pull test on the real thing, that is the PA- Sensor and Sensor-Sensor bonds on modules, 1 every 50th wire). Then these bonds have do be redone  Add the above pull test data to Bonding Tables in DB At the moment we do not envision this as a permanent test procedure, but only for the startup (first ~20 Modules per Center) and will be reduced to a sampling test or stopped altogether if found not to be needed.  I will gather results of the above pull tests from DB and report them to future Module Production meetings as part of the QA of the module bonding. Centers that do not report (satisfactory) results will not be considered “ready” for production.

17 July 2003Tracker Week - Module Production8 Salvatore Costa - Catania Breakage in TOB modules Drop tests carried out at UCSB.  A short or complete glue line between PA and Sensor did provide protection against shock breakage. Three modules have been sent to CERN without and with this additional glue.  None damaged. A vibration test of TOB modules with and without additional glue was performed in Aachen.  Improved resistance to breakage of the modules with additional glue. Will have to investigate  Minimum amount of glue needed to ensure protection  How the addition glue will modify module thermal characteristics.