Abstract
In this study, we have evaluated electromigration performance of W-plug vias, fabricated with process variations in via hole etching as well as in via barrier deposition, on a TiN(barrier)/AlCu/TiN metallization system. We found that via etch profile scheme as well as deposition conformity for via barrier can significantly affect W-plug via lifetimes. The results indicate that the quality of contact with AlCu layer of bottom level metal is a critical factor in determining via lifetime. Precise control of via etching or by use of conformal via barrier to ensure a good barrier between W-plug and the AlCu of bottom level metal is essential for achieving reliable via structures.
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Ting, L.M., Dixit, G., Jain, M. et al. Effect of Via Etch Profile and Barrier Metal on Electromigration Performance of W-Filled Via Structure in TiN/AlCu/TiN Metallization. MRS Online Proceedings Library 391, 453 (1995). https://doi.org/10.1557/PROC-391-453
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DOI: https://doi.org/10.1557/PROC-391-453