The CMS High Granularity Calorimeter Scintillator/SiPM Tileboards

The new CMS High Granularity Calorimeter (HGCAL), being built for HL-LHC, will have unprecedented transverse and longitudinal readout and trigger segmentation. In regions of low radiation, HGCAL will be equipped with small plastic scintillator tiles as active material coupled to on-tile silicon photomultipliers. With respect to earlier developments targeted at a future e+e-collider, additional challenges in terms of radiation hardness, data rates and mechanical integration including cooling need to be addressed. We will present the evolving design, results on the performance of irradiated SiPMs, the optimisation of scintillator tiles, the status of active element prototypes with integrated electronics, and the preparations for automated production.