Collected charge of planar silicon detectors after pion and proton irradiations up to 2.2 ×1016 neq cm−2

Abstract

The planned luminosity upgrade of the Large Hadron Collider at CERN (Super-LHC) will provide a challenging environment for the tracking and vertexing detector systems. Planar, segmented silicon detectors are one of the few radiation tolerant technologies under consideration for use for the Super-LHC tracking detectors in either pixel or strip geometries. In this paper, charge collection measurements are made with planar silicon sensors with 2 different substrate materials (float zone and magnetic Czochralski) and 3 different diode configurations (p+ strip in n-bulk, n+ strip in n-bulk, and n+ strip in p-bulk).For the first time, a comparison of the charge collection of these devices will be made after irradiation up to 6 ×1014neqcm−2 with 280MeV charged pions, and up to 2.2 ×1016neqcm−2 with 26MeV protons. This study covers the expected range of final fluences for the different layers of pixel and microstrip sensors of the ATLAS and CMS experiments at the Super-LHC. These measurements have been carried out using analogue, high-speed (40MHz) electronics and a Strontium-90 beta source.