Compare min metal pitch for Intel’s “10nm” (36nm) and TSMC’s “7nm” (40nm) [1]
Compare min metal pitch for Intel’s “10nm” (36nm) and TSMC’s “7nm” (40nm) [1]
Then there's the question of why they aren't skipping 10nm if 7nm is so ahead.
And theres the question of why they can't 'scale up' their 7nm to do 10nm.
So manufacturing 10n, with UV is much harder than manufacturing 7nm with EUV (although it is more expensive).
I've been out of that loop for a while, so I don't know how the design of the EUV machines turned out.
Apparently, tiny droplets of tin are created by spinning some disk(s) and then those droplets are zapped with with a laser before they emit EUV. Those machines are crazy complex.
[0] https://www.anandtech.com/show/14175/tsmcs-5nm-euv-process-t...
[1] https://www.anandtech.com/show/14312/intel-process-technolog...
And although "2020" and "2021" look like actual dates, they aren't; all they are is marketing labels, because saying you're going to do something in 2020 is cheap.
So what we know is that TSMC say they are going to begin volume manufacturing of "5nm" chips in "2020" (reality: at some unknown date they will be making large quantities of chips on a process to which they have found it convenient to attach the label "5nm"), and that Intel say they are going to launch "7nm" chips in "2021" (reality: at some unknown date they will be making unknown quantities of chips on a process to which they have found it convenient to attach the label "7nm").
Whether TSMC's "2020" is really earlier than Intel's "2021", and whether TSCM's "5nm" is really denser than Intel's "7nm", who knows?
(I'd guess TSMC are in fact ahead, but this isn't a field where you want to be trusting manufacturers' announcements much.)