par Adams, W.;Barria, Patrizia ;Caillol, Cécile ;Clerbaux, Barbara ;De Lentdecker, Gilles ;Dobur, Didar ;Favart, Laurent ;Grebenyuk, Anastasia ;Lenzi, Thomas ;Leonard, Alexandre ;Maerschalk, Thierry ;Mohammadi, Abdollah ;Pernie, Luca ;Randle-Conde, Aidan Sean ;Reis, Thomas ;Seva, Tomislav ;Thomas, Laurent ;Vander Velde, Catherine ;Vanlaer, Pascal ;Wang, Jian ;Zenoni, Florian ; [et al.]
Référence Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 803, page (100-112)
Publication Publié, 2015
Référence Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 803, page (100-112)
Publication Publié, 2015
Article révisé par les pairs
Résumé : | The response of n+p silicon strip sensors to electrons from a 90Sr source was measured using a multi-channel read-out system with 25 ns sampling time. The measurements were performed over a period of several weeks, during which the operating conditions were varied. The sensors were fabricated by Hamamatsu Photonics on 200 μm thick float-zone and magnetic-Czochralski silicon. Their pitch was 80 μm, and both p-stop and p-spray isolation of the n+ strips were studied. The electrons from the 90Sr source were collimated to a spot with a full-width-at-half-maximum of 2 mm at the sensor surface, and the dose rate in the SiO2 at the maximum was about 50 Gy(SiO2)/d. After only a few hours of making measurements, significant changes in charge collection and charge sharing were observed. Annealing studies, with temperatures up to 80 °C and annealing times of 18 h showed that the changes can only be partially annealed. The observations can be qualitatively explained by the increase of the positive oxide-charge density due to the ionization of the SiO2 by the radiation from the β source. TCAD simulations of the electric field in the sensor for different oxide-charge densities and different boundary conditions at the sensor surface support this explanation. The relevance of the measurements for the design of n+p strip sensors is discussed. |