New technologies of silicon position-sensitive detectors for future tracker systems

In view of the new generation of high luminosity colliders, HL-LHC and ILC, a farther investigation of silicon radiation detectors design and technology is demanded, in order to satisfy the stringent requirements of the experiments at such sophisticated machines. In this thesis, innovative technologies of silicon radiation detectors for future tracking systems are proposed. Three dierent devices have been studied and designed with the help of dierent tools for computer simulations. They have been manufactured in the IMB-CNM clean room facilities in Barcelona and characterized with proper experimental set-ups in order to test the detectors capabilities and the quality and suitability of the technologies used for their fabrication. The rst technology deals with the upgrade of dedicated sensors for laser alignment systems in future tracker detectors. The design and technology of common single-sided silicon microstrip detectors have been slightly modied in order to improve IR light transmittance of the devices. The layout of the sensors has been designed following the hints of optical simulations and the fabrication process has been properly monitored, obtaining a nal transmittance of 50% with a baseline pitch of 50m. The second device is a novel 2D position sensitive detector based on the standard technology of single-sided AC coupled, silicon microstrip detectors in which resistive coupling electrodes made of polysilicon have been integrated. The resistive charge division method, applied reading out the resistive electrodes at both ends, can be used to obtain spatial information on the coordinate of an ionizing event along the strip length. The prototypes fabricated, characterized with a laser set-up, showed a longitudinal spatial resolution of about 1.1% of the total strip length (20 mm) for a 6 MIPs signal. A Spice-like model of the detector has been developed and crosschecked with the experimental results, providing a good tool for future prototypes optimization. Finally, the last proposal deals with the new design, fabrication and rst characterization of dual-column stripixel detectors. The device consists of dual-column electrodes (both n+ and p+-type) arranged in a diamond conguration on one side of the n-type silicon bulk and connected by two sets of perpendicular strips organized in two separated metal layers that allow a X-Y projective readout of the sensor. The design has been optimized with the use of TCAD Sentaurus simulations and 2D position sensitivity has been demonstrated reconstructing the position of a laser beam within a pixel dened by two consecutive p+-type strips crossing two consecutive n+-type strips. The spatial resolution obtained was 23 m. The preliminary studies, the fabrication and characterization methods along with the experimental results are presented and discussed in the dedicated chapters of this thesis.