Effects of Y or Gd addition on the structures and resistivities of Al thin films

The addition of Y or Gd to Al thin films markedly decreases the grain size of the Al matrix and largely suppresses growth of hillocks at high temperatures (350–450 °C) associated with a large number of segregated metallic compounds, mostly at grain boundaries. The resistivities of the films after annealing at those high temperatures are less than 50 nΩ m. These tendencies also hold true for other Al rare‐earth alloy systems. The breakdown voltage of anodically oxidized films of Al–Y and Al–Gd alloys is higher than that of pure Al thin films.