Sensors for the CMS High Granularity Calorimeter

The CMS experiment is currently developing high granularity calorimeter endcaps for its HL-LHC upgrade. The design foresees silicon sensors as the active material for the high radiation region in the electromagnetic section and the forward region of the hadronic part. Regions of lower radiation are equipped with plastic scintillator tiles. This technology is similar to the calorimeter prototypes developed in the framework of the Linear Collider by the CALICE collaboration. The current status of the silicon sensor development is presented. Results of single diode measurements are shown as well as tests of full 6-inch hexagonal sensor wafers. A short summary of test beam results concludes the report.