Deferred action of illumination on the relaxation of a granular silver film when it is thermally annealed

It has been detected that UV radiation in the 300–400 nm wavelength interval affects the rate and final result of subsequent thermal annealing of a thin silver film on a sapphire substrate. Whereas the annealing of unirradiated films rapidly causes them to decay and causes the formation of individual fine particles of round shape, larger particles of irregular shape are formed when irradiated films are annealed, while the changes themselves occur significantly more slowly.