INTAS Collaborative Call with CERN 2005: TOSTER, TOtem STrip Edgeless Radiation hard detectors

The objective of the program is to extend the potential of semiconductor detectors targeted to close-to-beam applications. This is the case of the LHC TOTEM. Experiment that will place silicon detectors in special beam insertions (Roman Pots) as close as possible to the beam, to track protons elastically scattered from the interaction point 5 of the LHC. The program is inspired by the encouraging results seen on the silicon detectors already developed for the TOTEM Roman Pots where a current terminating structure (CTS) allows the reduction of the dead region surrounding the sensitive volume to less than 50µm against the standard terminations that can be even wider than 1mm for high voltage applications. The first results have show a very effective surface current suppression with detector current flowing in the sensitive volume 1000 times lower than the current flowing across the cut of the die, enabling to reach a dark current of only few nA’s per strip channel and to maintain the regular detector sensitivity. Test beam results have also proven that the efficiency of these devices rises steeply at the end of the terminating structure. The main task of this program is the study of the radiation stability of these devices and the development of techniques to enhance their radiation hardness. Along with the device topology engineering, the project will combine the last achievements in engineering of radiation hard silicon. In particular silicon grown by Magnetic-Czochralski technology with high concentration of oxygen will be used as well. The results of this project will produce a new knowledge on the semiconductor detector physics and new semiconductor detector technology. Prototypes of detectors will be processed and delivered to the TOTEM experiment for evaluations and tests with radiation beams.