1. 25.2.2003Sensor meetingF. Hartmann 1 Status report St & HPK plus add. Scratch tests. IEKP – University of Karlsruhe Frank Hartmann

2. 25.2.2003Sensor meetingF. Hartmann 2 QTC (sensors from JAN & FEB) Optical inspection of KA-Set 10 &11 (33/35) Electrical results of –KA-Set 10/1 W5B (8/8) –KA-Set 10/2 W5B (13/13) –KA-Set 11/1 W6B(5/10) –KA-Set 11/2 W6B(4/4) –KA-Set H5 W1TID(3/37) Some high IV  “I-t” –Some currents are improving with time – MANY sensors at the IV limit Possible explanation for the high IV and discrepancy of CMS & ST measurements.

3. 25.2.2003Sensor meetingF. Hartmann 3 Optical inspection KA-S10/1 Batch 31850 W5B Del. 9.1.2003 KA-S11/1 Batch 32961 W6B 9.1.2003 KA-S11/2 Batch 39728 W6B 9.1.2003 KA-S10/2 Batch 37528 W5B (11/13) Del. 9.1.2003

4. 25.2.2003Sensor meetingF. Hartmann 4 2 Sensors class „C“ 3021102318502130211023752820 IV OK!  2 rejects!

5. 25.2.2003Sensor meetingF. Hartmann 5 KA Set S10 (21 sensors W5B)

6. 25.2.2003Sensor meetingF. Hartmann 6 KA Set S10 ---- global

7. 25.2.2003Sensor meetingF. Hartmann 7 KA Set S11 (9/14 sensors W5A)

8. 25.2.2003Sensor meetingF. Hartmann 8 KA Set S11 ---- global

9. 25.2.2003Sensor meetingF. Hartmann 9 Comparison of Datas For 17 sensors no data available ! (~50% data still missing!!!!!!) Good agreement for pinholes, shorts and Rpoly! Ileak & CaC not measured by ST  Add. defective strips have scratches! no add. Pinholes due to scratches! Higher current @ 450V due to scratches! QTC & ST agree on IV up to the additional ~linear~ increase!

10. 25.2.2003Sensor meetingF. Hartmann 10 Same IV up to “soft strip breakdown” First strip Second strip

11. 25.2.2003Sensor meetingF. Hartmann 11 Summary of QTC KA-S10/1KA-S10/2KA-S11/1KA-S11/2 Optical inspected 8/811/1310/104/4 measured7/812/134/103/4 Failures Opt/IV/ strips 1/0/01/0/0 1/1/01/1/0 0/0/00/0/00/0/00/0/0 Accepted %8784100

12. 25.2.2003Sensor meetingF. Hartmann 12 I-t @ 450V 1. 2. 10µA 5 µA 7 µA 5 µA Saturation not yet reached

13. 25.2.2003Sensor meetingF. Hartmann 13 I-t @ 550V Min not reached! 12 µA 8 µA

14. 25.2.2003Sensor meetingF. Hartmann 14 I-t @ 550V over night 30211223972812

15. 25.2.2003Sensor meetingF. Hartmann 15 Improvements of IV e.g. 30211023752813 I-t (~10 min) between each IV-curve !

16. 25.2.2003Sensor meetingF. Hartmann 16 IV-problem 5 from 6 sensors improved, but… –they needed ~20 min or longer to reach the specified limit! –each sensor has a few „high leaky“ strips! –Σ leaky strips ~ IV (  few strips drive IV) – EACH leaky strip is scratched ! Attention: standard test with “I-t” would had have jected 6 instead of 1

17. 25.2.2003Sensor meetingF. Hartmann 17 Leaky strips 30211223972812 strip 49 30211223972812 strip 282

18. 25.2.2003Sensor meetingF. Hartmann 18 Leaky strips (2) 30211223972812 strip 282 30211223972816 strip 3

19. 25.2.2003Sensor meetingF. Hartmann 19 Leaky strips (3) 30211223972816 strip 14 30211223972816 strip 476 ?

20. 25.2.2003Sensor meetingF. Hartmann 20 Solving/Explaining the problem!?!??? Clear correlation between IV and leaky strips and scratches on sensors observed! No IV-breaks on Minisensors !  Handling !  Scratch test: –Scratchtest on minisensors to reproduce effect Needle Pencil (2B) screwdriver

21. 25.2.2003Sensor meetingF. Hartmann 21 Scratches on Minisensor „Soft“ scratches with probe needle Carbon residues of pencil

22. 25.2.2003Sensor meetingF. Hartmann 22 Deep scratches on Minisensor „Not-so-SOFT“ scratches with screwdriver

23. 25.2.2003Sensor meetingF. Hartmann 23 IV of ST-minisensor x3

24. 25.2.2003Sensor meetingF. Hartmann 24 ILeak (regard strips 8-15) A few single strips show high leakage current!

25. 25.2.2003Sensor meetingF. Hartmann 25 Ileak ramps on scratched strips x 70 All ramps on screwdriver scratched minisensor! The ramp behavior is similar to the global IV!

26. 25.2.2003Sensor meetingF. Hartmann 26 Correlation strip current  IV Correlation  strip current  IV Undamaged minisensor @ 400V: Ileak ~ 0,2nA x 192 strips ~ 35nA IV ~ 38nA Damaged minisensor @ 400V:  Ileak damaged strips ~ 55nA  Ileak all ~ 100nA IV ~ 120nA High IV behavior is driven by some leaky strips !

27. 25.2.2003Sensor meetingF. Hartmann 27 Similar defect in CDF sensors Defect in the p+ layer!! BUT: scratches do not effect p+ (  no pinholes!)

28. 25.2.2003Sensor meetingF. Hartmann 28 Idiel on scratched Minisensor Pinholes should be here ! Effect is located in the Al layer, above the oxide!

29. 25.2.2003Sensor meetingF. Hartmann 29 Summary of scratch-test Scratches increase individual strip leakage current Some few leaky strips drive high IV “Hard” mechanical force necessary to damage sensor! ALL unscratched minisensors show GOOD IV ! ALL leaky strips are scratched, but not all scratched strips are leaky ! Pinholes??? –no pinholes produced in scratch-test –no big differences between data of ST and QTC (w.r.t. pinholes)  Effect is located in the Al layer, not the p+ layer  CMS sensors have metal strip overhang!!!!

30. 25.2.2003Sensor meetingF. Hartmann 30 HPK W1TID qualification PQC fine, but quite low depletion voltages BTC OK Masks: postponed -- should be done in Vienna, cause CMM breakdown in KA QTC: fine, but quite low depletion voltages! –Very low total leakage currents. –3/27 sensors measured (no single strip failure)

31. 25.2.2003Sensor meetingF. Hartmann 31 KA SET H5 (3/37 W1TID)

32. 25.2.2003Sensor meetingF. Hartmann 32 KA SET H5 --- global