1. Noise in TOB modules and sensor quality
Regina Demina
University of Rochester

2. Module 876 Of the 16 modules tested at UCSB,
Observed peculiarity in module testing :
Noise on some channels increases with bias voltage.
Micro discharge effect (also seen in D0 sensors delivered by Micron)

3. Module 876
Defects in channels 278 and 279. Not found in sensor probing

4. Module 876

5. Module 877
Defect (scratch) in channel 333. Not found in sensor probing

6. Module 877

7. Module 878
Defect in channel 377. Not found in sensor probing

8. Module 878

9. Module 880
Strip 91 a known pinhole in the first sensor.

10. Module 880

11. Module 868
Mid-sensor opens in channels in the 1st sensor

12. Module 868

13. Module 883
Defect in channel 166. Not found in sensor probing

14. Module 883
Scratch in channel 316

15. Module 883

16. Module 872
Defect in channel 303. Not found in sensor probing

17. Module 872
Scratch in channel 344. Not found in sensor probing

18. Module 872

19. Summary Module # Comments
Channel 384 has high noise, but no lithography error present. NOT SEEN IN SENSOR PROBING
Found High Istrip channel in 2nd sensor (294) causes noise. Remove between sensors and module is good
873 Micro-discharge at channel 14 at 270 V (need to pluck to remove cmn). No obvious sensor damage. NOT SEEN IN SENSOR PROBING
872 4 channels with noise increase with HV. 3 have obvious lithographic error. NONE SEEN IN SENSOR PROBING
871 Micro-discharge at channel 181 at 300 V (need to pluck to remove cmn). No obvious sensor damage. NOT SEEN IN SENSOR PROBING
870 Good
883 Channel 166 has increasing noise with HV. Has lithographic error (see picture). NOT SEEN IN SENSOR PROBING
882 Good

20. Summary Module # Comments
881 Micro-discharge at channels (need to pull to stop high cmn).
Channels start discharging at 0V and get worse
869 Micro-discharge at channels (need to pull to stop high cmn) at 400 V
868 3 mid-sensor opens, lithographic error (see photo). NOT FOUND IN SENSOR PROBING
880 NO PROBLEMS
879 NO PROBLEMS
878 Channel 377 has increasing noise vs bias. Lithographic error found in second sensor (see picture).
NOT SEEN IN SENSOR PROBING
877 Channel 334 has slightly higher noise at 550 V. Lithographic error found in first sensor. (See picture.)
NOT FOUND IN SENSOR PROBING
876 Channels have increasing noise vs. bias voltage. Sensor lithographic error found on both channels (see picture) NOT FOUND IN SENSOR PROBING

21. Summary Out of 16 modules built 11 show some signs of micro discharge.
Total number of noisy strips – 17
Number of strips with high I strip – 1
Number of strips with obvious lithographic error – 8
Opens - 3

22. Module 875

23. Module 874

24. Module 873

25. Module 871

26. Module 870

27. Module 882

28. Module 881

29. Module 869

30. Module 879