Competition between surface and strain energy during grain growth in free-standing and attached Ag and Cu films on Si substrates

Abnormal grain growth and texture change in both free-standing and attached Ag and Cu films after annealing at 300 °C for 2 h have been investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). XRD texture analysis showed that both Ag and Cu films deposited on the (0 0 1)-oriented single-crystal Si substrates had (1 1 1) and (1 0 0) double fiber textures. θ/2θ scanning XRD patterns showed that, after annealing, the free-standing Ag and Cu films showed a slight increase in the (1 1 1) texture, on the contrary, both Ag and Cu films attached on Si substrates showed an increase in (1 0 0) and (1 1 0) textures. Four anomalous large grains with same (2 1 1) orientation were observed in attached Cu films after annealing by TEM. The experimental results have been explained satisfactorily from anisotropy of surface energy and strain energy.