Planar Pixel Sensors for the ATLAS Upgrade: Beam Tests results

TL;DR

This paper reports beam test results of planar silicon pixel sensors designed for the ATLAS upgrade, demonstrating their charge collection capabilities after high radiation exposure.

Contribution

It provides new empirical data on the performance of n-in-n and p-type silicon sensors under HL-LHC radiation conditions.

Findings

Sensors maintain charge collection after high fluences

Both n-type and p-type sensors perform effectively

Performance varies with irradiation and sensor layout

Abstract

Results of beam tests with planar silicon pixel sensors aimed towards the ATLAS Insertable B-Layer and High Luminosity LHC (HL-LHC) upgrades are presented. Measurements include spatial resolution, charge collection performance and charge sharing between neighbouring cells as a function of track incidence angle for different bulk materials. Measurements of n-in-n pixel sensors are presented as a function of fluence for different irradiations. Furthermore p-type silicon sensors from several vendors with slightly differing layouts were tested. All tested sensors were connected by bump-bonding to the ATLAS Pixel read-out chip. We show that both n-type and p-type tested planar sensors are able to collect significant charge even after integrated fluences expected at HL-LHC.