Silicon is ubiquitous. It is the most common, versatile, and pure material in the electronics industry, and it lends itself to myriad applications in particle physics detectors. One of our main activities involves using a large quantity of planar silicon sensors (600 m²) in the high granularity calorimeter (HGCAL) in the Compact Muon Solenoid (CMS) at the High Luminosity Large Hadron Collider (HL-LHC). When completed in 2026, the integrated neutron fluences will exceed 10¹⁶ neutrons per cm² for the HGCAL, so it is absolutely critical that we understand the processes that are at work in radiation damage and are able to simulate and quantitatively predict diminishing detector performance under irradiation for any application. We have been investigating many different test structures and sensors and characterizing their properties. Some of the results are in our papers