skip to main content

DOE PAGESDOE PAGES

Title: Trapping in irradiated p+-n-n- silicon sensors at fluences anticipated at the HL-LHC outer tracker

The degradation of signal in silicon sensors is studied under conditions expected at the CERN High-Luminosity LHC. 200μm thick n-type silicon sensors are irradiated with protons of different energies to fluences of up to 3 x 1015 neq/cm2. Pulsed red laser light with a wavelength of 672 nm is used to generate electron-hole pairs in the sensors. The induced signals are used to determine the charge collection efficiencies separately for electrons and holes drifting through the sensor. The effective trapping rates are extracted by comparing the results to simulation. The electric field is simulated using Synopsys device simulation assuming two effective defects. The generation and drift of charge carriers are simulated in an independent simulation based on PixelAV. The effective trapping rates are determined from the measured charge collection efficiencies and the simulated and measured time-resolved current pulses are compared. Furthermore, the effective trapping rates determined for both electrons and holes are about 50% smaller than those obtained using standard extrapolations of studies at low fluences and suggests an improved tracker performance over initial expectations.
Authors:
 [1]
  1. Institut fur Hochenergiephysik der Osterreichischen Akademie der Wissenschaften (HEPHY), Vienna (Austria). et al.
Publication Date:
OSTI Identifier:
1212720
Report Number(s):
FERMILAB-PUB--15-249-CMS
Journal ID: ISSN 1748-0221; arXiv eprint number arXiv:1505.01824
Grant/Contract Number:
AC02-07CH11359
Type:
Accepted Manuscript
Journal Name:
Journal of Instrumentation
Additional Journal Information:
Journal Volume: 11; Journal ID: ISSN 1748-0221
Publisher:
Institute of Physics (IOP)
Research Org:
Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
CMS Collaboration, Tracker Group
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY