416 Chapter 6. Scintillation Detectors and Photodetectors
Bulk Damage:This occurs when the lattice atoms in the bulk of the material
get displaced from their usual sites through incident particle impacts. An atom
displaced in such a way creates a defect site that can trap electrons and thus
contribute to the dark current.
Surface Damage:The incident radiation can also create similar defect on the
surface of the APD’s active volume, decreasing the quantum efficiency of the
detector.