Speaker
Description
The absorption length of near-infrared light in radiation-damaged silicon has to be known to
calculate the deposited charge in irradiated sensors relative to non-irradiated reference sensors.This
is required in order to determine the charge collection efficiency CCE using the transient current
technique TCT. The absorption length has been determined as a function of the wavelength and the
temperature for silicon irradiated with protons to fluences between 9E14-1.3E16$~n_{eq}/cm^{2}$.
Highly irradiated silicon sensors can be operated under forward bias where the electric field is
expected to be to a good approximation constant. We investigate charge profiles of strip sensors
obtained with edge TCT under forward bias. The charge collection lengths of electrons and holes are
extracted as a function of the particle fluence and the electric field at -20 °C and -30 °C. A
parameterization of the charge collection length from edge TCT measurements is compared to CCE
measurements with pad diodes for fluences between 3E15-1.3E16$~n_{eq}/cm^{2}$.
