James R. Lloyd, Michael W. Lane, et al.
IEEE T-DMR
An in situ electromigration apparatus was used to study the kinetics of void growth in unpassivated, electropolated copper damascene lines. Voids were observed to grow by consuming grains in a stepwise fashion, either by grain thinning or by an edge displacement mechanism. Surface diffusion was found to be the primary diffusion path for void growth. In addition, grain boundaries provided a secondary path for copper diffusion in polycrystalline structures and nucleation sites for void growth in bamboo structures. Void growth rate was measured as a function of sample temperature and linewidth using a scanning electron microscope. An electromigration activation energy of 0.9±0.1 eV was determined for the copper voiding process. The effect of linewidth on void growth rate was also investigated and found to be negligible, consistent with a surface-diffusion dominated model for void growth. The in situ apparatus also made it possible to directly correlate changes in electrical resistance with physical changes taking place in the test structures. © 2002 American Institute of Physics.
James R. Lloyd, Michael W. Lane, et al.
IEEE T-DMR
C.-K. Hu, L. Gignac, et al.
MRS Fall Meeting 2007
J.M.E. Harper, C. Cabral Jr., et al.
MRS Spring Meeting 1999
K.P. Rodbell, E.G. Colgan, et al.
MRS Spring Meeting 1994