Characterization of planar and 3D Silicon pixel sensors for the high luminosity phase of the CMS experiment at LHC

The High Luminosity upgrade of the CERN LHC collider (HL-LHC) demands for a new, high-radiation tolerant solid-state pixel sensor capable of surviving fluencies up to a few $10^{16}~ \rm{n_{eq}/cm^2}$ at $\sim 3 \, \rm{cm} $ from the interaction point. To this extent the INFN ATLAS-CMS joint research activity, in collaboration with Fondazione Bruno Kessler (FBK), is aiming at the development of thin n-in-p type pixel sensors for the HL-LHC. The R\&D covers both planar and single-sided 3D columnar pixel devices made with the Si-Si Direct Wafer Bonding technique, which allows for the production of sensors with 100\,$\mu {\rm m}$ and 130\,$\mu {\rm m}$ active thickness for planar sensors, and 130\,$\mu {\rm m}$ for 3D sensors, the thinnest ones ever produced so far. Prototypes of hybrid modules, bump-bonded to the RD53A readout chip, have been tested on beam. First results on their performance before and after irradiation are presented. \footnote{Published in Proceedings of Science as PoS(EPS-HEP2019)117, DOI: 10.22323/1.364.0117}