Phase structure and surface morphology evolution of Al–Ti–O films irradiated by electron beam

Al–Ti–O films were prepared on Si substrates by reactive magnetron sputtering technology. Then the as-deposited and annealed films were treated by electron beam irradiation. The phase structure and surface morphology of the films were investigated by scanning electron microscopy and atomic force microscopy. Especially, height–height correlation function measurement was introduced to quantitatively characterize the film surface evolution. The results show that both electron irradiation and annealing induce well-crystallization of as-deposited films, while the irradiation leads to the phase change of annealed films. In contrast to those of as-deposited films, the surface morphologies of annealed films exhibits roughening characteristic and steep local surface slope due to the formation of new phases and the preferred grain growth. The electron irradiation can result in a rougher surface due to the irradiation-induced structural damage.