LHCb PRR - Girish D. Patel1 QC and Process Control G. D. Patel

LHCb PRR - Girish D. Patel2 QA There exist various QA criteria for the different components that go into the manufacture of a VELO module plus a well defined procedure for their processing. My role is to ensure that the selection criteria are correctly applied and the procedures followed. To aid in this process I have designed, written and implemented a web based database system that holds all the information relating to all the components. All components are entered into the database upon arrival and the subsequent procedures in the processing of each component is defined by the database.

LHCb PRR - Girish D. Patel3 The database is designed to store all relevant information on the LHCb Velo detector in a central, web accessible location. It is implemented with an Apache web server running with a php interface to a MySQL database. Data input is restricted by password protection, but information retrieval is unrestricted. Information is stored on cables, chips, pitch adaptors, sensors, pedestals, substrates, hybrids and modules. All changes made to the database are logged and can be traced back to a specific user. All test data are stored and online analysis is possible. Database & Components

LHCb PRR - Girish D. Patel4 Cables Visual inspection and log in database. Send for population. Electrical tests. PASS/FAIL logged in database.

LHCb PRR - Girish D. Patel5 Chips Arrive in 11x11 waffle boxes, position in box identifies chip. Maximum of 120 chips, but gaps indicate rejected chips. Used chips have a link to the module on which they reside. Link to original chip test data at Max Planck web site is provided..

LHCb PRR - Girish D. Patel6 Pitch Adaptor Pre-selection at CERN. Visual inspection and log in database Must be no breaks or shorts in any of the 512 strips. Detected by a capacitance measurement of every strip. Data logged in the database. Algorithmic code implemented via the web server informs the operator if the pitch adaptor meets the QA requirements.

LHCb PRR - Girish D. Patel7 Problem channels identified and classified as shorts or breaks. Data presented graphically Web based code can be run before the data is logged in the database. This allows for re-measurements on the probe station before logging the final data. PASS/FAIL indicated

LHCb PRR - Girish D. Patel8 Pitch Adaptor DB Summary

LHCb PRR - Girish D. Patel9 Sensor 1.Metrology Must be no damage and shape must be with in limits of nominal. Shape metrology measurements from the Smartscope are logged in the database. Algorithmic code implemented via the web server informs the operator if the sensor shape meets the QA requirements.

LHCb PRR - Girish D. Patel10 Shape measurements analysed and compared with nominal shape. Any edges oversize or undersize outside of the specified tolerance are flagged and a software PASS or FAIL issued. Final decision on accept or reject taken by me after discussions. Undersize Oversize Software decision

LHCb PRR - Girish D. Patel11 Sensor 2.IV Currents Total current at maximum volts must be less than 100 μA. Data logged in database in text format. Code displays maximum current in red on summary page if over limit.

LHCb PRR - Girish D. Patel12 Sensor 3.Bad strips Measure capacitance per strip, must be within 20% of expected value. Measure current per strip, must be less than 1 μA. Algorithmic code implemented via the web server analyses the raw data from the probe-station and informs the operator of the numbers of strips which fail the capacitance and current criteria.

LHCb PRR - Girish D. Patel13 Summary of numbers of channels that failed (capacitance or current tolerance) Problem channels identified. Failed channels in red Warnings in green. This analysis available before the data is logged in the database Graphjcal presentations of data

LHCb PRR - Girish D. Patel14 All the test information is displayed on the sensor summary page. Physicist must look at the sensor summary page and the data and make a QA decision on the final status of the detector. Acceptable sensors are categorised as OK, GOOD or VERY GOOD. I inform Micron if a sensor is to be rejected. Sensor

LHCb PRR - Girish D. Patel15 SensorthicknessTypeHybridIVCVCAP/S TCU R/S CURVCONTORStatusQA FlagUpdate D300/303r-04x/0-0-10Update D300/302r-04x/6-6-10Update A300/305phi-04x/14-10Update E300/302r-04x/ Update A300/299phi-04/ Update E300/298r-04x/ Update C300/302phi-04x/ /1-30Update A300/302phi-04x/ /2-30Update C300/301phi-04x/ Update E300/304r-04x/ Update D300/304r-04x/ Update D300/312r-04x/ Update B300/307phi-04x/ Update A300/308phi-04x/ Update D300/309r-04x/ Update E300/306r-04x/ Update B300/311phi-04x/ /06-10Update D200/201r-04x/ /1-37Update A300/310phi-04p-07x/ /07100Update Sensor DB summary

LHCb PRR - Girish D. Patel16 Sensor DB Summary

LHCb PRR - Girish D. Patel17 TPG and CF laminated in- house. Metrology data logged in database Sent to Stevenage for circuit to be laminated on the two side. Logged in the database on return Substrate

LHCb PRR - Girish D. Patel18 Metrology measurements to determine curvature and bowing. Those out of tolerance are heat treated between metal plates. Additional metrology measurements on the heat treated hybrids. Hybrids with acceptable QA are sent out for population. Rest are rejected Hybrid Stages 1-4

LHCb PRR - Girish D. Patel19 Populated hybrids are electrically tested to ensure specified functionality. Electrical test failures are rejected if they cannot be repaired. The rest are cleaned and inspected. Additional metrology measurements on those that pass electrical tests. Those that are too far from flatness required are rejected. Hybrid Stages 5-7

LHCb PRR - Girish D. Patel20 The hybrid is now ready for the gluing of pitch adaptors and chips. The database has a hold at this point and no further work is allowed unless specifically cleared to proceed by Tony Smith or Themis Bowcock Hybrid Stage 8

LHCb PRR - Girish D. Patel21 Batches of pitch adaptors and chips to be used taken from store. Glue pitch adaptors to R side. Visual inspection and fix problems. Glue chips to P side. Visual inspection and fix problems. All pitch adaptors and chips used are logged in the database Hybrid Stages 8-9

LHCb PRR - Girish D. Patel22 Glue pitch adaptors to P side. Visual inspection and fix problems. Glue chips to P side. Visual inspection and fix problems. All pitch adaptors and chips used are logged in the database Hybrid Stages 10-11

LHCb PRR - Girish D. Patel23 Bond back ends of R side chips. Visual inspection, repair problem bonds and log in DB. Bond back ends of Phi side chips. Visual inspection, repair problem bonds and log in DB. Bare chip test data to electrically test that all chips are working. Results via web database interface. Replace any problem chips and repeat the cycle till all chips OK. Hybrid Stages 12-16

LHCb PRR - Girish D. Patel24

LHCb PRR - Girish D. Patel25 Front end bond R side chips to pitch adaptors. Visual inspection, repair problem bonds and log in DB. Front end bond Phi side chips to pitch adaptors. Visual inspection, repair problem bonds and log in DB. Bare chip test data to electrically test that all bonds are working. Repair if necessary. Hybrid Stages 17-19

LHCb PRR - Girish D. Patel26 The hybrid is now ready for the gluing of sensors. The database has a hold at this point and no further work is allowed unless specifically cleared to proceed by Tony Smith or Themis Bowcock Hybrid Stage 20

LHCb PRR - Girish D. Patel27 Glue R and Phi sensors to hybrid. Log sensors used in the database. Metrology measurements to confirm the alignment of the sensors. Make bias bonds and check IV for the sensors. Bond R and Phi sensors to pitch adaptors. Quality of ALL bonds are logged and database informs operator of known problem channels on the sensors which are NOT to be bonded in terms of the bond numbers programmed in the bonding machine. Hybrid Stages 20-25

LHCb PRR - Girish D. Patel28 Information on known problem channels on the sensor are presented to the bonding machine operator. The bonds which are NOT to be made in the current pass are shown in RED Rest of this page allows status of every bond in this current pass to be entered and logged in the database.

LHCb PRR - Girish D. Patel29 Laser tests on all 4048 channels of R and Phi sensors. Correlate problem channels detected by laser scan with known bad channels and problem bonds. Investigate anomalies and resolve. Hybrid Stages 20-25

LHCb PRR - Girish D. Patel30 Glue complete hybrid to pedestal. The final module number is defined by the number engraved on the invar feet of the pedestal base. Full module metrology. Plug and clamp cables. Burn-in and thermographs Final metrology. Package for shipping. Hybrid Stages 26-32

LHCb PRR - Girish D. Patel31 A further selection of chips within the ones we receive may be required. Plan to implement web input so that Aldo Saavedra can input this information directly into the database. Front end bonding has recently been implemented on the 710 as a backup to the The bonding sequence and bond wire numbering is different and a separate input page for bonding problems has to be implemented and both machines supported. Algorithmic analysis of laser test data and cross correlation with known problem channels is still to be implemented. Analysis of burn-in data still to be implemented. Database software and data store to be transferred to a more powerful server machine. Outstanding Tasks

LHCb PRR - Girish D. Patel32 Conclusion The web based database system has proved invaluable for the logging and tracking of all the many components and their QA test data and results which are required for the VELO project. I am sure that the inbuilt process control will be an essential tool for the management of the production phase giving a constantly updated overview of the status of every module. Additional features will be added that give numerical summaries and provide lists of known bad channels for every module for input to the conditions database