Theory of aging by recombination-induced defect diffusion

Irradiation experiments and DLTS defect measurements have led to the development of a theory for the motion of defects in wide-band-gap solids where electron-hole recombination moves the defect. In the present work, the theory is applied to predict the motion of defects in insulators. Any defect or impurity which acts as a recombination center is subject to rapid diffusion by this process. Such defects are driven out of regions where the recombination rate is high and accumulate in regions where the recombination rate at the defect is low. If the recombination rate is uniform in the insulator, the defects continually wander in a random way and eventually accumulate at larger defect sites, especially if these large defects do not produce recombinations. The generalized theory is discussed as it applies to insulators. Exposure to light is especially interesting for insulators. The accumulation of defects is an aging process