Speaker
Sven Wonsak
(University of Liverpool (GB))
Description
The leakage current of irradiated silicon sensors depends, among others, on sensor temperature and irradiation fluence. The temperature dependence is parameterized with the activation energy E$_g$ and the fluence dependence with the current related damage rate $\alpha$. The literature values for E$_g$ and $\alpha$ are obtained from previous measurements, but $\alpha$ is only measured directly to a dose up to 1e15 1MeV neq/cm$^2$ (neq/cm$^2$).
Miniature micro-strip sensors ($\sim1\times1$cm$^2$) were irradiated with protons to fluences from 1e12 to 1e15 neq/cm$^2$ and with neutrons from 5e15 to 2e16 neq/cm$^2$ to investigate the reverse current at higher fluence. Precise temperature and current measurements of the sensors from Hamamatsu Photonics K.K. (300$\mu$m thick) and Micron Semiconductor Ltd. (143$\mu$m and 108$\mu$m thick) allow the determination of E$_g$ and $\alpha$. The sensors were measured shortly after irradiation and after room temperature annealing. For the devices irradiated to higher fluences the obtained values differ from the literature value of E$_g$ and the expected value from the linear extrapolation of $\alpha$.
Primary author
Sven Wonsak
(University of Liverpool (GB))
Co-authors
Gianluigi Casse
(University of Liverpool (GB))
Michael Wormald
(University of Liverpool (GB))
Paul Dervan
(University of Liverpool (GB))
Dr
Tony Affolder
(University of Liverpool (GB))
