Feb 18 – 22, 2019
Vienna University of Technology
Europe/Vienna timezone

Radiation damage in p-type EPI silicon pad diodes irradiated with different particle types and fluences

Not scheduled
Vienna University of Technology

Vienna University of Technology

Gusshausstraße 27-29, 1040 Wien
Board: 89
Poster Semiconductor Detectors Poster Session B


Yana Gurimskaya (CERN)


In view of the HL-LHC upgrade, radiation tolerant silicon sensors that contain low-resistivity p-type implants or substrates, like LGAD or HVCMOS devices, are being developed in the framework of ATLAS, CMS, RD50 and other sensor R&D projects. The devices are facing a particular problem - the apparent deactivation of the doping due to the irradiation, the so-called acceptor removal effect.
In the present work proton- and neutron-fluence dependent radiation damage effects, including change in leakage current and effective doping concentration, space charge sign inversion, but also introduction and annealing of point- and cluster-defects have been studied in Si pad diodes fabricated from p-type EPI material of different resistivity (10-1000 ohm∙cm). Standard electrical characterizations (I-V, C-V), TCT (Transient Current Technique) and TSC (Thermally Stimulated Current) techniques were applied.
A correlation between effective doping concentration obtained from C-V measurements and defect concentration Nc extracted from TSC measurements for both neutron and proton irradiation is observed and pointing towards the microscopic origin of the acceptor-removal.
A detailed analysis of the dominant TSC peaks - E(30K), BiOi and three main deep acceptor levels H(116K), H(140K) and H(152K) - responsible for the changes in the effective space charge is performed. The origin and annealing behavior of E(30) and H(40) and other cluster-related defects are discussed as well.

Primary authors

Yana Gurimskaya (CERN) Isidre Mateu (CERN) Pedro Dias De Almeida (Universidad de Cantabria (ES)) Marcos Fernandez Garcia (Universidad de Cantabria (ES)) Michael Moll (CERN)

Presentation materials