Study of depth-dependent charge collection profiles in irradiated pad diodes

TL;DR

This study investigates how charge collection in irradiated and non-irradiated p-type pad diodes varies with depth, using experimental measurements and comparing results to different radiation damage models.

Contribution

It provides detailed depth-dependent charge collection profiles for irradiated diodes and evaluates the accuracy of existing radiation damage models.

Findings

Charge collection efficiency decreases with higher irradiation fluences.

Experimental profiles are compared with three radiation damage models.

Results help improve understanding of radiation effects in silicon detectors.

Abstract

In this work, charge collection profiles of non-irradiated and irradiated 150 $\mu$m $p$-type pad diodes were measured using a 5.2 GeV electron beam traversing the diode parallel to the readout electrode. Four diodes were irradiated to 1 MeV neutron equivalent fluences of 2, 4, 8, and 12E15 {cm}^{-2} with 23 MeV protons. The Charge Collection Efficiency profiles as a function of depth are extracted by unfolding the data. The results of the measurements are compared to the simulation using three radiation damage models from literature which were tuned to different irradiation types and fluences.