Electron beam induced growth of silver nanowhiskers

In this paper we report an electron beam induced rapid (up to several tens of nm/s) growth of silver nanowhiskers from silver nanowire networks coated with TiO₂ by sol-gel method. Different growth conditions are tested and it is demonstrated that growth is optimal for samples with the film thickness in the range 50-200 nm and previously annealed at 400°C for 5-10 min. Growth mechanism is attributed to cooperative effect of several factors including diffusion of Ag into TiO₂ matrix during annealing, electromigration of Ag atoms caused by strong electric field, and presence of mechanical stresses at interfaces enhanced by thermal expansions due to local heating under e-beam illumination.