Functional characterization of 3D-DDTC detectors fabricated at FBK-irst

We present selected results from the functional characterization of 3D-Double-Sided Double-Type Column (3D-DDTC) detectors fabricated at FBK, Trento. This technology features columnar electrodes etched perpendicularly to wafer surface and not passing all the way through the wafer thickness, stopping at short distance from the opposite surface. The detectors under investigation come from the first batch of these devices, made on n-type substrates. We report on the performances of microstrip sensors before and after irradiation up to 2×10¹⁵cm⁻² fluences. The characterization has been carried out using a micrometer position resolved infrared laser scan and a ⁹⁰Sr Beta source setup.