The degradation of signal in silicon sensors is studied under conditions
expected at the CERN High-Luminosity LHC. 200 $mu$m thick n-type silicon
sensors are irradiated with protons of different energies to fluences of up to
$3 cdot 10^{15}$ neq/cm$^2$. 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. 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.
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.