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Title: Avalanche Effect in Si Heavily Irradiated Detectors: Physical Model and Perspectives for Application

Abstract

The model explaining an enhanced collected charge in detectors irradiated to 10{sup 15}-10{sup 16} n{sub eq}/cm{sup 2} is developed. This effect was first revealed in heavily irradiated n-on-p detectors operated at high bias voltage ranging from 900 to 1700 V. The model is based on the fundamental effect of carrier avalanche multiplication in the space charge region and in our case is extended with a consideration of p-n junctions with a high concentration of the deep levels. It is shown that the efficient trapping of free carriers from the bulk generation current to the deep levels of radiation induced defects leads to the stabilization of the irradiated detector operation in avalanche multiplication mode due to the reduction of the electric field at the junction. The charge collection efficiency and the detector reverse current dependences on the applied bias have been numerically simulated in this study and they well correlate to the recent experimental results of CERN RD50 collaboration. The developed model of enhanced collected charge predicts a controllable operation of heavily irradiated detectors that is promising for the detector application in the upcoming experiments in a high luminosity collider.

Authors:
; ; ; ;
Publication Date:
Research Org.:
BROOKHAVEN NATIONAL LABORATORY (BNL)
Sponsoring Org.:
USDOE SC OFFICE OF SCIENCE (SC)
OSTI Identifier:
1049221
Report Number(s):
BNL-96759-2012-JA
Journal ID: ISSN 0168-9002; NIMAER; KA-04; TRN: US1204414
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nuclear Instruments and Methods in Physics Research, Section A; Journal Volume: 658; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CERN; CHARGE COLLECTION; DEFECTS; DISTRIBUTION; EFFICIENCY; ELECTRIC FIELDS; HARDNESS; LUMINOSITY; P-N JUNCTIONS; RADIATIONS; SILICON; SPACE CHARGE; STABILIZATION; TOWNSEND DISCHARGE; TRAPPING

Citation Formats

Eremin V., Li Z., Verbitskaya, E., Zabrodskii, A., and Harkonen, J. Avalanche Effect in Si Heavily Irradiated Detectors: Physical Model and Perspectives for Application. United States: N. p., 2011. Web. doi:10.1016/j.nima.2011.05.002.
Eremin V., Li Z., Verbitskaya, E., Zabrodskii, A., & Harkonen, J. Avalanche Effect in Si Heavily Irradiated Detectors: Physical Model and Perspectives for Application. United States. doi:10.1016/j.nima.2011.05.002.
Eremin V., Li Z., Verbitskaya, E., Zabrodskii, A., and Harkonen, J. 2011. "Avalanche Effect in Si Heavily Irradiated Detectors: Physical Model and Perspectives for Application". United States. doi:10.1016/j.nima.2011.05.002.
@article{osti_1049221,
title = {Avalanche Effect in Si Heavily Irradiated Detectors: Physical Model and Perspectives for Application},
author = {Eremin V. and Li Z. and Verbitskaya, E. and Zabrodskii, A. and Harkonen, J.},
abstractNote = {The model explaining an enhanced collected charge in detectors irradiated to 10{sup 15}-10{sup 16} n{sub eq}/cm{sup 2} is developed. This effect was first revealed in heavily irradiated n-on-p detectors operated at high bias voltage ranging from 900 to 1700 V. The model is based on the fundamental effect of carrier avalanche multiplication in the space charge region and in our case is extended with a consideration of p-n junctions with a high concentration of the deep levels. It is shown that the efficient trapping of free carriers from the bulk generation current to the deep levels of radiation induced defects leads to the stabilization of the irradiated detector operation in avalanche multiplication mode due to the reduction of the electric field at the junction. The charge collection efficiency and the detector reverse current dependences on the applied bias have been numerically simulated in this study and they well correlate to the recent experimental results of CERN RD50 collaboration. The developed model of enhanced collected charge predicts a controllable operation of heavily irradiated detectors that is promising for the detector application in the upcoming experiments in a high luminosity collider.},
doi = {10.1016/j.nima.2011.05.002},
journal = {Nuclear Instruments and Methods in Physics Research, Section A},
number = 1,
volume = 658,
place = {United States},
year = 2011,
month = 5
}
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