Study On Stress Migration Behavior In Narrow Copper Lines
- Conference date: 4–7 April 2007
- Location: Kyoto (Japan)
Stress migration (SM) behavior in Cu damascene interconnects was investigated in detail using different kinds of test patterns. In the pattern in which narrow lines are connected to wide metal, the failure rate decreased as the narrow metal becomes longer, and the failure rate in minimum 0.14 μm wide lines is more than that in 0.42 μm wide lines. The result of the test patterns with different via arrangements clarified that the placing of the vias at the edge of the M1 line plays an important role in the SM phenomenon in narrow copper lines. Failure analysis using scanning transmission electron microscopy revealed voiding beneath the via at the failure points. It is shown that the enhanced failure rate in the minimum wide lines and the via arrangement effect cannot be understood by the previous diffusion mechanism. Based on these results with the stress simulation calculated by finite element method, the effect of the via arrangement close to the edge of the lower lines on SM failure in narrow lines will be discussed.
- Failure analysis
- Finite element methods
- Scanning transmission electron microscopy
MOST READ THIS MONTH
MOST CITED THIS MONTH
Article metrics loading...