Semiconductors

Migrating Industrial DfM into IC Manufacturing 43

Cu, showing that interlevel diffusion barrier layers promote EM by mecha-

nisms faster than grain boundary self-diffusion.

A stress gradient due to atoms driven out of the cathode end of the conduc-

tor and accumulating at the anode end modulates not only the wire width

but also the atomic density along it. When the wires are shorter than a value

called the Blech length (about 10 µm), a mechanical stress causes reverse

material migration to compensate the EM mass transport toward the anode.

As this may result in a false reliability reading, JEDEC (Joint Electron Device

Engineering Counci ...