Investigation of thin n-in-p planar pixel modules for the ATLAS upgrade

TL;DR

This paper evaluates thin n-in-p planar pixel modules for the ATLAS detector upgrade, focusing on their radiation hardness, efficiency, and cost-effectiveness for high-luminosity LHC conditions.

Contribution

It presents recent results on irradiated and non-irradiated n-in-p planar pixel modules, highlighting their suitability for the HL-LHC upgrade.

Findings

High edge efficiency demonstrated in beam tests

Radiation hardness confirmed for thin sensors

Cost-effective single-sided processing advantage

Abstract

In view of the High Luminosity upgrade of the Large Hadron Collider (HL-LHC), planned to start around 2023-2025, the ATLAS experiment will undergo a replacement of the Inner Detector. A higher luminosity will imply higher irradiation levels and hence will demand more ra- diation hardness especially in the inner layers of the pixel system. The n-in-p silicon technology is a promising candidate to instrument this region, also thanks to its cost-effectiveness because it only requires a single sided processing in contrast to the n-in-n pixel technology presently employed in the LHC experiments. In addition, thin sensors were found to ensure radiation hardness at high fluences. An overview is given of recent results obtained with not irradiated and irradiated n-in-p planar pixel modules. The focus will be on n-in-p planar pixel sensors with an active thickness of 100 and 150 um recently produced at ADVACAM. To maximize the active area of the sensors, slim and active edges are implemented. The performance of these modules is investigated at beam tests and the results on edge efficiency will be shown.