1. Preparation for Production Testing of EndCup ITk sensors
Marcela Mikestikova, Jiri Kroll
Institute of Physics CAS, Prague

2. Time scale for the production testing of ITk Strips
Sensor pre-production Q1-Q2 2018
Sensor testing start Q ? (1year, 5%)
Series production Q3 2018
Sensor testing starts 2019? (3 years)
Ingrid M. Gregor, Valencia 2016

3. Number of sensors to be tested
(Without spare)

4. No of sites involved in EC sensor testing
DESY – Hamburg
DESY Zeuten
Valencia
Prague
Canada Carleton
Canada Triumph
Scandinavien cluster

5. Specifications for ITk Sensor Production Testing
Tests performed on every sensor:
Action
Equipment needed
Quality Control Specs
Storage of Components
Storage Cabinets, Dry
Visual Inspection
Check for scratches, blemishes, trace continuity, sensor edge roughness. bias rail and guard ring
Optical Microscope with automated inspection software
No chips or cracks,
clean sensor
Sensor bow
Non-contact Coordinate Measurement Machine
SCC
Total bow < 200um IV
V with 10V/10s
Probe station with N2/humidity control/chiller,
SCC, or Dry
Room Temperature
No onset of micro-discharge up to 700V CV
V with 10V/5s
As above
FDV<330V
Definitions:
Standard Cleanroom Conditions (SCC): Temperature = 19+/-1oC, Relative Humidity = 40+/-10 %
Dry atmosphere: Relative Humidity < 5% at 21oC. Could be air or N2

6. Specifications for ITk Sensor Production Testing
Tests on a subset of sensors (10-1% of total), all at SCC:
ActionData
Equipment needed
Quality Control Specs
Full Strip tests
Rbias, Ccoupling, Ileakage
on every strip
Automatic Probe Station
Switching matrix
Number of strips with problem (pinhole, shorts, opens, implant breaks…) <2%
Current stability test
at Vbias=-700V
Probe-station or a test box
Dry, 20°C
Current variation less then 3% in 24Hours
Additional tests
Cint,
Rint,
PTP,
Top metal resistance
Probe station
1 pF/cm at 300V at 1khz
GOhms range at 600V (not irrad)
< 15Ohm/cm
Database
Sensor is registered
Data uploaded PC

7. EC Sensor rate Same as for barrels Longer
Calculation for a site with one 1 probe station:
100% of sensors
- Visual inspection,
- Metrology
- IV,CV
- Sensor registration in database
1:40 hours/sensor = 4 sensors/day or
Tests on a subset of sensors (starts at 10% then reduced to 1% of total),
- Full strip tests: ~14 hours/sensor with single needle method - overnight running possible
~5 hours/sensor with EC specific multi-channel probecard
(includes 4 aligments for 4 segments)
- PTP, Cint, Rint 
- Current stability (24h running in a test box, multiple sensors at a time, parallel measurement)
1 sensors/ day
e.g. one site ~1000 sensors = > = 350 days
Same as for barrels
Longer

8. Full strip tests – barrel sensors
Rbias, Ccoupling, Ileakage on every strip
For barrel sensors the testing contact pads are in line
Cambridge developed measurement set-up with a custom 32 channel low-leakage probecard with associated switching and multiplexing equipment.
Measurement time around 14 hours with single needle was reduced to less than 3 hours.

9. Full strip tests – EC sensors specific
6 different end-cap sensor designs
Wedge shaped strips with a stereo angle of 20 mrad implemented in the sensors

10. Full strip tests – EC sensors specific
2 or 4 Columns of strips on a sensor
Contact pads on circular arch
Different pitch of contact pads in each Column
The angle between neighbour strips, the angular pitch, is constant on each segment. It May, however, differ among segments.
Number of strips in columns differs
(e.g. R0: Column 1 and 2 : 1024 strips ,
Column 3 and strips)
200×56 µm AC pads R0
Full strip tests of EC sensors
Much more difficult than barrel ones

11. Full strip tests – EC sensors specific
The single needle strip probing
- the probe station chuck is moved to test every single channel individually
- accepts any pad location, as it loads the pad coordinates from a file
- Task: prepare the contact pad file map
- the ATLAS12EC Technical Specs provides values and formulae to
compute the start and end point of the strips
- Q: What is the location of contact AC pads on a strip?
- 14 hours testing of one sensor

12. Full strip tests – EC sensors specific
a custom EC multi-channel probe card with associated switching equipment
wedge-shaped probe card x straight-shaped probe card
more expensive max. number of channel to be calculated
the movement of chuck during each measurement step: shift and rotation
4 types of probe-card for a single sensor needed due to different pitch and curvature of contact pads in each column
Each column of strips needs a new alignment of multi-channel probe card
Time consuming and demanding for manpower
Q: still worth it? Depends on number of sensor and sensor types tested by a site.

13. Wedge-shaped probe card
Price: ~$1800 for BNC coaxial connectors, ~1/2 for row of contacts

14. Straight-shaped probe card
Cambridge probecard £360

15. Some considerations for the chuck
Probe-station vacuum chuck
- previously experienced mechanical stress
Plastic vacuum jig with the sensor clamped down to avoid mechanical stress and micro-cracking
- advantages: guaranteed HV operation with no breakdowns
jig can be used independently of a probe station for e. g. long term
tests under controlled environment conditions
- drawbacks: difficult to machine to flatness of < 20um
requires a wire-bonding which may not be achievable (large dimension)
Suggestion: High Voltage chuck with vacuum pattern designed for thin devices
Typical hole pattern for thin RF devices,
i.e. < 100um thickness

16. Institute of Physics CAS Prague, Strip meeting, Aug 31, 2016
Cambridge lab visit
July 25-26, 2016: Marcela and Jiri (Prague) and Robert H. (Ottawa) in Cambridge lab
Lab excursion
Detailed discussion on lab equipment, measuring instruments and set-up with Switching Matrix and Multiplexer for full strip scan testing
Intensive training of full strip testing with the multichannel card
Bonding presentation
Many thanks to Bart and Chris
Institute of Physics CAS Prague, Strip meeting, Aug 31, 2016

17. Preparation of Production Testing of EC sensors in Prague
Aiming at production of ~1000 endcap modules in the Czech Republic
Production testing of ~1000 endcap sensors in Institute of Physics, CAS Prague
Infrastructure:
Clean room and semi-clean room
Automatic probe station KarlSuss PA200
equipped with probe heads with vacuum and magnetic support,
microscope , video camera and monitor
Measuring devices:
LCR meter HP4284A
SMU Keithley 237
HP34401A multimeter
Picoammeter Keithley 487
Electometer K6517A
HV Supply K248 up to 3000V
Switching system
4x5 Matrix Switch
Clean storage cabinet with Nitrogen purge for ~200 sensors

18. Preparation of Production Testing of EC sensors in Prague
Set - up prepared for large area sensors tests:
IV, CV
surface studies: Cint, Rint, Ccoupl, DC PTP, Rbias
full strip tests with a single needle (barrel sensors)
sensor fixed to the chuck by vacuum (no issue with mechanical stress observed so far)
Probe needle manipulator contacting the bias rail fixed to the moving chuck
ATLAS07 barrel sensor

19. Preparation of Production Testing
of EC sensor in Prague
In progress …
Set-up for mutli-channel sensor testing system
Prague lab has a new equipment (same as Cambridge):
12 x 4 Switching matrix module
2x Dual 8 channel Multiplexer
Switch Unit crate
RS232/IEEE488.2 Interface Card
Power Supply Unit
search for a external company to produce the EC specific multichannel probe card
preparation of long-term stability set-up independently of probe station
Sensor on a jig will be enclosed in metal box with electrical connections and N gas inlet
Cambridge jig

20. Preparation of Production Testing of EC sensor in Prague
Invest plan in 2017
OGP SmartScope CNC 500
Keithley 2410 SourceMeter
Flowbox
XYZ travel: 500×450×200 mm
XYZ scale resolution :0.5 µm
Sensors:
Zoom 12 AccuCentric optics
CNC TTL laser
DRS Laser
Touch Probe TP 200

21. Preparation of Production Testing of EC sensor in Carleton
All smaller electronic test equipment purchased

22. backup

24. Evaluation of the Market survey sensors in Prague
Set - up prepared for large area sensors
IV, CV
surface studies
full strip scan tests
Preparation of a jig for testing of large irradiated sensors in fridge ongoing
the bias rail, backplane and tested strips will be bonded to solderable contacts
plastic jig will be enclosed in metal box with electrical connections and N gas inlet