It won't answer your question directly (especially if you just read the free material instead of obtaining the whole book) but it should orient you for further reading. Note that electromigration is sensitive to temperature. Running cooler can extend the lifetime non-linearly, whether achieved via lower duty cycles or more effective cooling methods. You need to know how many years at what temperature the processor will run, not just the dimensions of the conductors.
Comments
This "Fundamentals of Electromigration-Aware Integrated Circuit Design" appears to be a decent starting point:
https://www.ifte.de/books/em/
https://www.ifte.de/books/em/em_chap1_figs.pdf
https://www.ifte.de/books/em/em_chap2.pdf
It won't answer your question directly (especially if you just read the free material instead of obtaining the whole book) but it should orient you for further reading. Note that electromigration is sensitive to temperature. Running cooler can extend the lifetime non-linearly, whether achieved via lower duty cycles or more effective cooling methods. You need to know how many years at what temperature the processor will run, not just the dimensions of the conductors.