Lab-measurement results on IZM thin assemblies

Mathieu Benoit

Outline

• Assembly process

• Methodology

• Results

Sensor production and procurement : Bumping at IZM

Micron Sensor Wafer were sent to IZM for Under-Bump Metallization and assembly to Timepix and Medipix3RX ASIC• 10 Sensor wafers processed by IZM

• Thickness: 100,150,200,300,650,1500 um • wafer <= 200 um thickness attached to handle

wafer for processing

100um-on-100um assembly

Methodology• After wire-bonding, chip is powered,

sensor biased at 40V• Chip threshold equalization is

performed twice, mask pattern is written to disk– First equalisation lead to weird masked

pixel pattern (checkboard)– Second equalization works usually fine

• An image of a Sr90 source is taken with Exposure time of 30s (every pixel should see some energy deposition)

• A simple algorithm count how many pixel see no or too little signal (<20% of neighbors) and compare to mask

C03-W0126 (100-on-100um) Masked pixels

C03-W0126 (100-on-100um) Sr90, 30s Exposure

229 masked pixel in C03-W012635567 pixel with no Sr90 in C03-W0126

J08-W0126 (100-on-100um) Masked pixels

J08-W0126 (100-on-100um) Sr90, 30s Exposure

56 masked pixel in J08-W012656 pixel with no Sr90 in J08-W0126

J10-W0126 (100-on-100um) Masked pixels

J10-W0126 (100-on-100um) Sr90, 30s Exposure

190 masked pixel in J10-W0126195 pixel with no Sr90 in J10-W0126

K04-W0126 (100-on-100um) Masked pixels

K04-W0126 (100-on-100um) Sr90, 30s Exposure

52 masked pixel in K04-W012652 pixel with no Sr90 in K04-W0126

K05-W0126 (100-on-100um) Masked pixels

K05-W0126 (100-on-100um) Sr90, 30s Exposure

28 masked pixel in K05-W012639 pixel with no Sr90 in K05-W0126

K06-W0126 (100-on-100um) Masked pixels

K06-W0126 (100-on-100um) Sr90, 30s Exposure

31 masked pixel in K06-W012631 pixel with no Sr90 in K06-W0126

Conclusion• New assemblies show pretty good yield for the bumping of 100um ASIC to

100um Sensors (5/6 perfect sensors)

• Only one assembly with a catastrophic failure, plan to send it back to IZM for further X-Ray study, chip was fine before wire-bonding– Ian mention that assemblies were quite fragile– Maybe lift-off occurred during wire-bonding process

• 4 more assemblies with 150um n-in-p on 100um currently at the bonding lab

This is now our thinnest full functional module we ever did using this technology.I forwarded this results immediately to all colleagues involved in this task.

Thomas Fritzsch, IZM

Hitmap, 100 on 100 um Assemblies

Unconnected pixels