Kahng says chipmakers may face a more immediate struggle with wiring in just a few years as they attempt to push chip density down past the 10-nm generation. Each copper wire requires a sheath containing barrier material to prevent the metal from leaching into surrounding material, as well as insulation to prevent it from interacting with neighboring wires. To perform effectively, this sheath must be fairly thick. This thickness limits how closely wires can be pushed together and forces the copper wires to shrink instead, dramatically driving up the resistance and delays and drastically lowering performance. Although researchers are exploring alternative materials, it’s unclear, Kahng says, whether they will be ready in time to keep up with Moore’s Law’s steady pace.