IIRC, 7nm is five Si atoms.
..............
Thanks. For I surely have no understanding of the underlying physical laws. Do you know why 5 silicon atoms and not 4 or 6 is the limit?
Thanks. For I surely have no understanding of the underlying physical laws. Do you know why 5 silicon atoms and not 4 or 6 is the limit?
Basically what happens is that there are doublings not in terms of feature length but in terms of area (7 squared is about half of 10 squared).
So it says that there just aren’t too many doublings left.
The limit is determined by the diffusion limit which is set by the wavelength of light shining through the masks. Extreme ultraviolet has a shorter wavelength than deep ultraviolet (from lasers) currently in use, so it can make smaller features. There are huge challenges moving to EUV Light. There’s a pretty technical explanation at http://en.m.wikipedia.org/wiki/Extreme_ultraviolet_lithography.
EUVL is a significant departure from the deep ultraviolet lithography used today. All matter absorbs EUV radiation...the optics (mirrors and lenses) alone absorb 96% of the available EUV light, so the EUV source will need to be sufficiently bright. Research is focused on plasmas generated by laser or discharge pulses. The mirror responsible for collecting the light is directly exposed to the plasma and is therefore vulnerable to damage from the high-energy plasma ions and other debris.
This is tougher than rocket science!