Characterisation of a semi 3-D sensor coupled to Medipix2

A 300 μ m thick semi-3D Si sensor has been characterised after bump-bonding to a Medipix2 read-out chip. The bonding quality measured using a 90Sr-source was found to be excellent ( > 99.9 % ) . Comparative measurements with respect to a standard planar 300 μ m Si sensor comprising IV-curves, depletion voltage and energy resolution have been performed. IV-curves and depletion voltages correspond to the values expected from the sensor geometry. The depletion voltage of the semi-3D sensor is significantly lower than the one of the planar sensor. The energy resolution of the semi-3D device has been found to be lower. The uniformity of the pixel response has been measured using a pulsed 1060 nm laser.