I have read a few papers on the role of texture and grain size in electromigration MTTF. The most famous work on this is the Vaidya-Sinha equation which says MTTF depends on grain size & distribution and the ratio of to texture.
However I was told that texture is no longer relevant in PVD/ ECP Copper lines which are today's processes and that grain size is only slightly relevant, but texture can be totally neglected. The EM failure mechanisms are more dominated by the interface with capping layers.
Can anybody point me to some articles/sources explaining or dismissing the role of texture and microstructure.