ELECTRON IRRADIATION-INDUCED DYNAMIC FLUCTUATIONS IN AMORPHOUS STRUCTURES

High resolution, transmission electron microscopy results of dynamic observations during the electron irradiation of amorphous phases are presented. The granular image contrast, typical in amorphous structures, fluctuates continuously during high flux irradiation. The fluctuations tend to occur locally in the structure, whereas crystalline regions remain stable. Some local structures are identified during the fluctuations and anisotropic movements are observed at surfaces and interfaces. The phenomenon is attributed to the irradiation-induced instability of a random cluster network, resulting in a decrease of the viscosity and local deformation.