What is Electromigration?
The movement of metal atoms in interconnects caused by electric current. It creates voids and hillocks that lead to open or short circuits.
Field: Reliability
Electromigration in the explanations
In electromigration, atoms are pushed along by the electron flow (the electron wind).
Where are voids due to electromigration likely to form?When electromigration drives atoms in one direction, a stress gradient builds along the line that drives a counterflow (backflow).
In electromigration testing, wires shorter than a certain l…Fast diffusion paths along the wire's length disappear, suppressing grain-boundary electromigration—a major lifetime boost for aluminum lines.
When a wire becomes narrower than its grains so that grain …
Questions that mention Electromigration (21)
- In Black's equation for wire lifetime under electromigration, which factors shorten the lifetime?
- Where are voids due to electromigration likely to form?
- In electromigration testing, wires shorter than a certain length show greatly extended lifetimes, with almost no degradation. What is this phenomenon called?
- When a wire becomes narrower than its grains so that grain boundaries line up across the wire, what is this structure called, and how does it affect electromigration?
- Which correctly describes electromigration?
- Which failure can occur when electromigration creates a hillock on a wire?
- Which statistical distribution is commonly used to describe the times to failure of many wires in electromigration life tests?
- When electromigration in flip-chip solder bumps becomes a problem due to large currents, where are failures known to be especially likely?
- What is the cause of self-heating, which tends to be a problem in FinFETs and SOI transistors?
- Which deposition method has mainly been used to form aluminum wiring films?
- What is the main reason the wiring material of advanced LSIs was changed from aluminum (Al) to copper (Cu)?
- Which metal has been widely used to fill contact holes connecting transistors to the lowest wiring layer?
- What is the main purpose of placing a cap layer such as cobalt on top of copper wiring?
- What problems occur when copper filling is incomplete and a void remains in a via?
- Why has an Al-Cu alloy with about 0.5% copper been used for aluminum wiring?
Related terms
Black's equation CMP MTTF (mean time to failure) Mobility Sputtering Dry etching CVD Selectivity Yield Preston's equation