Direct real-time observations of electromigration (EM) in submicron Al interconnects were made using a special sample-stage which allowed TEM observations to be recorded while simultaneously heating and passing current through the sample. The samples consisted of 4000Å thick Al(0.5wt%Cu) patterned over a TEM-transparent window into five runners in parallel, with linewidths 0.2, 0.3, 0.5, 0.8, and 1.0μm. Both passivated and unpassivated samples were examined. A current density of 2 x 106A/cm2 was used with temperatures ranging from 200 - 350°C. The experiments were done using constant voltage testing, and we used a special sample design which dramatically minimized Joule-heating. Our approach has allowed us to directly observe voids form, grow, migrate, pin, fail a runner, and heal, all with respect to the detailed local microstructure of the runners.
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R. Kirchheim, Mat. Res. Soc. Symp. Proc., ed. by K.P Rodbell, W.F. Filter, H.J. Frost, and P.S. Ho, 309, 1993, p. 101.
M.A. Korhonen et al., AIP Conference Proc., 305, Stress Induced Phenomena in Metallization, ed. P.S. Ho, C.Y. Li, P. Totta, p. 15, 1993.
H.J Frost and C.V. Thompson, Ibid, p. 254.
Previous in-situ methods have examined much wider runners, e.g.: I. A. Blech and E.S. Meieran, J. Appl. Phys., 40, 485 (1969). High-voltage SEM methods have also been used: T.N. Marieb et al, AIP Conference Proc., 305, Stress Induced Phenomena in Metallization, ed. P.S. Ho, C.Y. Li, P. Totta, p. 1, 1993.
Note on Figures 3-7: these micrographs were obtained by “frame-grabbing” from a video tape. A slight defect in the oil-immersion lens of the camera produced a line near the middle-to-right hand side of each micrograph.
J.E. Sanchez, O. Kraft, and E. Arzt, Appl. Phys. Lett., 61, 3121 (1992).
S.P. Riege, A.W. Hunt, and J.A. Prybyla, in progress, to be submitted to J. Appl. Phys.
A.W. Hunt, S.P. Riege, and J.A. Prybyla, In-Situ TEM Observations of Healing Dynamics of Electromigration-Failed Interconnects, submitted to Appl. Phys. Lett.
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Riege, S.P., Hunt, A.W. & Prybyla, J.A. Real-Time Tem Studies of Electromigration in Submicron Aluminum Runners. MRS Online Proceedings Library 391, 249 (1995). https://doi.org/10.1557/PROC-391-249