Operation
Current induced local oxidation also uses a small electrical current, but in a very different way. We pass a current through a small constriction (~100 nm wide), resulting in a high current density that approaches the level at which electromigration effects begin. Microscopic voids then start to congregate around grain boundaries in the film, creating high diffusivity paths for reactive oxygen to travel down through the native oxide. This local enhancement of the oxidation process leads to the formation of oxide barriers as the oxide grows from the surface down into the film. Heating caused by the current is also believed to have an effect.