Underground Testing and Characterization of Skipper CCD Modules for DAMIC-M

The DAMIC-M experiment uses silicon skipper CCDs to explore the frontier of low-mass dark matter searches at the Laboratoire Souterrain de Modane (LSM) in France. We present the current status of underground testing and characterization of the CCD detector modules, validating stable performance across a large array of devices. The results provide important benchmarks of detector response under low-background conditions, informing both calibration and optimization, and demonstrating readiness for scaling to the full DAMIC-M array. We will also report on the construction status of the kg-scale detector, planned for 2026.