There is academic effort that has been working on a similar concept for 8+ years. A recent paper that also discusses some of the challenges (routing around defe

There is academic effort that has been working on a similar concept for 8+ years. A recent paper that also discusses some of the challenges (routing around defects, ...) is https://www.frontiersin.org/articles/10.3389/fnins.2019.01201/full https://www.frontiersin.org/articles/10.3389/fnins.2019.0120... . If you dig into the publications and PhD theses conducted on this system, you will also find partial answers to some of the issues raised here in the comments (how to interconnect reticles, power supply (the first prototype had really scary centimeter thick copper bars that supplied the wafer). There is a second generation system in development..