Title :
Low-temperature bump bonding of Timepix readout chips and CdTe sensors at Different Sensor pitches
Author :
Heikkinen, Hannele ; Gädda, Akiko ; Vähänen, Sami ; Salonen, Jaakko ; Monnoyer, Philippe ; Blaj, Gabriel ; Tlustos, Lukas ; Campbell, Michael
Author_Institution :
VTT Tech. Res. Center of Finland, Espoo, Finland
Abstract :
The article describes a low temperature bump bonding process to flip chip bond CdTe sensors on Timepix readout chips with two separate pixel pitches: 55 μm and 110 μm. Because the sensor properties of CdTe start to degrade around 150 °C, InSn (48-52) solder joints were used. The solder bumping process flow and flip chip bonding routine are described, and leakage currents and radiation images are compared at different pitches. The results show low leakage currents and a good bump bonding yield with both pitches.
Keywords :
nuclear electronics; readout electronics; semiconductor counters; CdTe sensor properties; Timepix readout chips; flip chip bonding routine; leakage currents; low-temperature bump bonding process; radiation images; sensor pitches; size 110 mum; size 55 mum; Bonding; Image edge detection; Nickel; Tin;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE
Conference_Location :
Valencia
Print_ISBN :
978-1-4673-0118-3
DOI :
10.1109/NSSMIC.2011.6154712
