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http://dx.doi.org/10.6117/kmeps.2015.22.1.021

Bending Fatigue Reliability Improvements of Cu Interconnects on Flexible Substrates through Mo-Ti Alloy Adhesion Layer  

Lee, Young-Joo (Department of Materials Science & Engineering, Seoul National University)
Shin, Hae-A-Seul (Department of Materials Science & Engineering, Seoul National University)
Nam, Dae-Hyun (Department of Materials Science & Engineering, Seoul National University)
Yeon, Han-Wool (Department of Materials Science & Engineering, Seoul National University)
Nam, Boae (LG Display Research and Development Center, LG Display Co. Ltd.)
Woo, Kyoohee (Advanced Manufacturing Systems Research Division, Korea Institute of Machinery and Materials)
Joo, Young-Chang (Department of Materials Science & Engineering, Seoul National University)
Publication Information
Journal of the Microelectronics and Packaging Society / v.22, no.1, 2015 , pp. 21-25 More about this Journal
Abstract
Bending fatigue characteristics of Cu films and $8{\mu}m$ width Cu interconnects on flexible substrates were investigated, and fatigue reliability improvement was achieved through Mo-Ti alloy adhesion layer. Tensile bending fatigue reliability of Cu interconnects is 3 times lower than that of Cu films, and even compressive bending fatigue reliability of Cu interconnects is 6 times lower than that of Cu films. From these results, mechanical crack formation could be fatal in Cu interconnects. With Mo-Ti adhesion layer, fatigue reliability of Cu films and interconnects were enhanced due to the increase of adhesion strength and the suppression of slip induced crack initiation.
Keywords
Flexible interconnects; Fatigue; Reliability; Bending endurance;
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Times Cited By KSCI : 2  (Citation Analysis)
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