A comparative study of radiation damage on high resistivity silicon

¹ LERMAT ISMRA (UPRESA 6004), 6 boulevard Maréchal Juin, 14050 Caen, France
² INFN, Sezione di Milano, via Celoria 16, 20100 Milano, Italia

Corresponding author: levalois@labolermat.ismra.fr

Received: 13 July 1998
Revised: 20 November 1998
Accepted: 18 January 1999
Published online: 15 May 1999

Abstract

In future particle accelerators, silicon detectors will be exposed with large doses of different types of radiation. To understand the corresponding produced damage mechanisms, a systematic study of the influence of the irradiation on the silicon from which the detectors are made has to be carried out. Samples of low n-doped silicon have been irradiated with swift krypton ions , neutrons from a nuclear reactor and energetic electrons . Resistivity and Hall effect measurements performed after irradiation show that the silicon is changed to a quasi-intrinsic state, characterized by a very high resistivity. The electrically active defects responsible for that evolution are Maynly acceptor centers, namely divacancy and/or vacancy-doping complexes. Besides, for the highest fluences, only the appearance of a donor center located at about 0.59 eV below the conduction band may explain the observed stabilization of the Fermi level at 0.61 eV. Finally, using a simulation method, the rates of generation of the different defects are estimated.