The CMS Pixel Detector for the High Luminosity LHC

The High Luminosity Large Hadron Collider (HL-LHC) at CERN is expected to collide protons at a centre-of-mass energy of 14 TeV and to reach the unprecedented peak instantaneous luminosity of $5$--$7.5\times 10^{34}$ cm$^{-2}$s$^{-1}$ with an average number of pileup events of $140$--$200$. This will allow the CMS experiment to collect integrated luminosities up to $3000$--$4000$ fb$^{-1}}$ during the project lifetime. The current CMS pixel detector cannot sustain the expected radiation levels and data rates foreseen at HL-LHC and thus a completely new Inner Tracker will be installed in order to fully exploit the delivered luminosity under the highly demanding conditions. The new pixel detector will feature increased radiation hardness, higher granularity and capability to handle a higher data rate and longer trigger latency. The design choices for the Inner Tracker Phase-2 upgrade are discussed along with some highlights on the technological approaches and R\&D activities.