Controlling Ag whisker growth using very thin metallic films

The selective growth of Ag nano-whiskers on polycrystalline films was realized by introducing an additional artificial layer onto the films. Ag nano-whiskers with diameter ∼200 nm and length ∼3 μm were successfully generated from Ag films covered with a 1-nm-thick SiO 2 layer. However, the formation of Ag whiskers/hillocks on the top surface of the film could be suppressed using thick SiO 2 layers or ductile Au layers.