Defect behavior in aluminum interconnect lines deformed thermomechanically by cyclic joule heating
Roy H. Geiss, David T. Read
Transmission electron microscopy (TEM) was used to study the defects introduced into PVD Al-1wt% Si lines on SiO2/Si substrates that were deformed thermomechanically by cyclic Joule heating induced by AC current. SEM observations revealed striking arrays of wavelike surface protrusions aligned along low index crystallographic directions, after a few tens of thousands of thermal cycles generating strain excursions of about 0.3 % per cycle. Here we report TEM observations of cross sections of selected regions that suggest that in favorably-oriented grains, dislocations were nucleated at the film-substrate interface, glided to the surface, and escaped, leaving the protrusions. In addition, we observed a high density of prismatic dislocation loops indicating that a large concentration of vacancies was created by dislocation glide and interaction during the cyclic deformation.
and Read, D.
Defect behavior in aluminum interconnect lines deformed thermomechanically by cyclic joule heating, Acta Materialia, [online], https://doi.org/10.1016/j.actamat.2007.09.033
(Accessed May 30, 2023)