Short answer: it isn't, this 3-nm is a marketing term, they keep redefining the term to use a lower and lower number. Transistor body dimensions is at or below

Short answer: it isn't, this 3-nm is a marketing term, they keep redefining the term to use a lower and lower number. Transistor body dimensions is at or below about 7nm start having some quantum effects. Here's a reddit post where there's more detail about the physics and science behind this: https://www.reddit.com/r/askscience/comments/itiuw8/how_are_chip_manufacturers_getting_around_quantum/ https://www.reddit.com/r/askscience/comments/itiuw8/how_are_...