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arXiv · 1410.4420

Achievements of the ATLAS Upgrade Planar Pixel Sensors R&D Project

C. Nellist
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Abstract

In the framework of the HL-LHC upgrade, the ATLAS experiment plans to introduce an all-silicon inner tracker to cope with the elevated occupancy. To investigate the suitability of pixel sensors using the proven planar technology for the upgraded tracker, the ATLAS Planar Pixel Sensor R&D Project (PPS) was established comprising 19 institutes and more than 90 scientists. The paper provides an overview of the research and development project and highlights accomplishments, among them: beam test results with planar sensors up to innermost layer fluences (> 10^16 n_eq cm^2); measurements obtained with irradiated thin edgeless n-in-p pixel assemblies; recent studies of the SCP technique to obtain almost active edges by postprocessing already existing sensors based on scribing, cleaving and edge passivation; an update on prototyping efforts for large areas: sensor design improvements and concepts for low-cost hybridisation; comparison between Secondary Ion Mass Spectrometry results and TCAD simulations. Together, these results allow an assessment of the state-of-the-art with respect to radiation-hard position-sensitive tracking detectors suited for the instrumentation of large areas.

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C. Nellist. 2014-10-16. Achievements of the ATLAS Upgrade Planar Pixel Sensors R&D Project. https://doi.org/10.1088/1748-0221/10/01/c01027

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