Movement of the atoms of a conductor due to the flow of charge carriers: the metal atoms are physically displaced from the solid crystal by collisions with the charge carriers and are moved in the direction of flow of the carriers. This effect occurs at high current densities, and is most noticeable in metals of low atomic mass. For example, the fine interconnecting lines on an integrated circuit have only a small cross-sectional area and can carry a very high current density even at modest currents. Electromigration can cause enough of the aluminium atoms to move so that the conductor is physically broken, resulting in a failure of the component.