Performance tests of large pitch silicon strip sensors for the LHCb inner tracker

Different multi-geometry silicon prototype sensors were designed and produced for the LHCb Inner Tracker. Silicon ladders have to be 22 cm long and the pitch of the sensors should be as large as possible in order to reduce costs of the readout electronics. Major design criteria are material budget, short shaping time in the order of 25 ns and a moderate spatial resolution of 80 μm. Sensors should be as thin as possible in order to minimize the multiple scattering of particles in the detector. The electrical characteristics of the sensors are presented. Laboratory and test beam results on resolution, signal-to-noise and efficiency are discussed. It has been found that the efficiency, especially in the inter-strip gap, is very sensitive to different tested geometries. Based on the results the decision will be made which geometry will be implemented in the final sensors for the LHCb Inner Tracker.