Speaker
Mr
David Vázquez Furelos
(IFAE - Barcelona)
Description
The ATLAS experiment will replace the entire inner tracking detector with a completely new silicon-only system. 3D silicon pixel sensors are promising candidates for the innermost layers of the Pixel detector due to their excellent radiation hardness and low power dissipation. 3D pixel sensors with 50x50 and 25x100 µm² pixel pitches have been produced at CNM Barcelona and studied by IFAE. The smaller pixel size will allow to cope with the increased particle rate at HL-LHC and in addition the reduced electrode distance is expected to increase the radiation hardness. Initial studies of the small pitch 3D sensor prototypes coupled to the FEI4 readout chip, presently used on the current innermost layer of ATLAS (pixel size 50x250) were performed in test beams at CERN SpS. A new chip with pixel size of 50x50 µm² (RD53 - compatible with both small pixels) is still under development.
Sensors of 50x50 and 25x100 µm2 pixel sizes were studied before irradiation. Also, 50x50 µm2 sensors were studied after uniform (at KIT to 5e15 neq/cm2) and non uniform irradiations (at CERN PS up to 1e16 neq/cm2). Two different types of telescopes were used to study the hit efficiency of the small pitch 3D sensors: an EUDET-type telescope in combination with the EUTelescope/TBMon2 reconstruction software and a custom-made FEI4 3D telescope in combination with the Judith reconstruction software. The EUTelescope/TBMon2 software was adapted to cope with the challenge that only one 50x50 µm² sub pixel within each 50x250 µm² FEI4 readout pixel is sensitive. The reconstruction of the FEI4 telescope data with Judith is also addressed.
Primary author
Mr
David Vázquez Furelos
(IFAE - Barcelona)
