4/2/2003p. riedler/cern spd team1 testing wafer test status annealing tests on vtt ladder
TRANSCRIPT
4/2/2003 P. Riedler/CERN SPD Team 1
Testing
• Wafer test status • Annealing tests on VTT ladder
4/2/2003 P. Riedler/CERN SPD Team 2
Wafer Test Status
Delivery 2000: 4 wafers fully tested- preliminary test criteria- installation of the setup
Delivery 2001: 12 wafers fully tested (from 3 lots)- 1 wafer tested in Catania- 1 wafer tested in Legnaro- test criteria applied- FO test not included
Total no. of chips tested: 1376
4/2/2003 P. Riedler/CERN SPD Team 3
Class I, II, III chips per Wafer
Delivery 2001:CLASS I: 33-74%CLASS II: 9-27%CLASS III: 22-51%
*4 wafers tested and classified by NA60** sample of 8 wafers
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806040200Number of class III chips
CLASS III5
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806040200Number of class II chips
CLASS II
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806040200Number of class I chips
CLASS I
4/2/2003 P. Riedler/CERN SPD Team 4
Annealing Tests
Singles: 2001 - 300µm detector
Increased leakage current observed on most singles and ladders from VTT
4/2/2003 P. Riedler/CERN SPD Team 5
VTT Ladders
2001: VTT1-2001: 1.2µA @ 80V (300µm) VTT2-2001: 3.1µA @ 80V (300µm)
2002:VTT1-2002: 17µA @ 15V (200µm)VTT2-2002: 14µA @ 20V (200µm)VTT3-2002: 28µA @ 20V (200µm)VTT4-2002: 280nA @ 80V (300µm)
Could the higher current be caused by humidity in the polyimide? Annealing could help……
4/2/2003 P. Riedler/CERN SPD Team 6
Candidate: Ladder-VTT-3-2002 (thin ladder) with damaged corner
99.7% 99.7% 99.9% 99.9% <80%90Sr:
Leakage Current: 28.8µA @ 20V (Vfd=15V)
Test Procedure:• measure Ileak, metrology, source test• -> Annealing• repeat measurements
4/2/2003 P. Riedler/CERN SPD Team 7
1. Before Annealing:
Leakage Current: 28.8µA @ 20V (Vfd=15V)
Long edge (on chips)Metrology:
4/2/2003 P. Riedler/CERN SPD Team 8
2. First Annealing Step: 48 hrs @ 120°C
Leakage Current: 11.1 µA @ 20V (Vfd=15V)
Metrology: Bow
Long edge (on chips): 53.13µm
3. Second Annealing Step: 136 hrs @ 140°C
Leakage Current: 3.3 µA @ 20V (Vfd=15V)
4/2/2003 P. Riedler/CERN SPD Team 9
Long edge (on chips)
4/2/2003 P. Riedler/CERN SPD Team 10
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Total Leakage Current [µA]
302520151050
Bias Voltage [V]
before baking after48hrs@120 °C after136hrs@140°C + 48hrs@120°C
Leakage Current
4/2/2003 P. Riedler/CERN SPD Team 11
4/2/2003 P. Riedler/CERN SPD Team 12
Mean Threshold
But baking is not without problems…….
4/2/2003 P. Riedler/CERN SPD Team 13
Chip 68 after baking
4/2/2003 P. Riedler/CERN SPD Team 14
Testbeam 2003
Proton Run: June 25 - July 9Proton Run: June 25 - July 9
H4Long MD June 25/26Short MD July 2
• Setup similar to 2002 (4 reference planes, crossed?)• Improvement of scintillator mounting to be done..• Program depends on progress in coming months…• Thin ladders!• Preparation should start well ahead
4/2/2003 P. Riedler/CERN SPD Team 15
Please join the testbeam crew !Please join the testbeam crew !
4/2/2003 P. Riedler/CERN SPD Team 16
Short edge (on sensor)
4/2/2003 P. Riedler/CERN SPD Team 17
Long edge (on sensor)