It also depends how you define "7 nm". Although it is supposed to be ~14 nm half-pitch by projection from previous nodes, I can't imagine gates accomodating this, for example. Lg hasn't been scaling that fast recently. It seems more likely to be stuck at say, around 20 nm half-pitch (which requires only double patterning), but there could be more layers patterned this way than previous nodes.
The drive lasers continue to fall short. Maybe they will reach the 43KW (in Cymer's case) needed, but that's just for minimum commercial viability. The current drive laser technology is far from practical as a means to build towards the cited ~1KW EUV needed for full sustainability of EUVL. Yet the two primary players have both chosen a path of non-interest in a new generation of CO2 laser technology that bypasses the limitations of the current ones. With volumetric extraction about 3 times as high, practically scalable, Helium free with low to no gas usage, coupled with low maintenance requirements and almost unlimited shelf and dynamic lifetime, one would expect such a laser design would be of interest to them.
If the benefits of a vastly improved drive laser is considered unimportant, one wonders just what plans they have made to mitigate not achieving EUVL as envisioned. Maybe they no longer believe in it and are pursuing tracks of which we are not yet aware.
Having attended both of the talks referenced in the article I was surprised by the articles optimistic title and tone. I thought the tone of the talks was generally negative. TSMC in particular really called out ASML not only on the source power but the source reliability as well.
I think in general the mood at the conference is skepticism on EUV and a growing confidence that the 14nm, 10nm, 7nm and even 5nm node can be done without it!
Gridded arrays are being adopted by logic greatly simplifying the difficulty of printing patterns.
Self-Aligned Quadruple patterning is being employed today to make cost effective 16nm NAND Flash. The emerging 3D NAND technologies are already producing 1x equivalent class NAND using 50nm lithography.
A number of talks showed novel combinations of multi patterning techniques with shrink technology that could meet logic requirements at least down to the 7nm node.
The next generation of immersion tools currently being introduced is capable of 250 wafers per hour increasing productivity and reducing cost.
Yes the idea of Octuple Patterning with up to 9 cut masks is economically daunting but there are a number of design and process technologies that can likely mitigate a lot of that. Smart designs, shrink techniques, etc. can all reduce the number of cut masks. There is also a lot of work being done on cost reducing multi patterning by simplification and less expensive material and equipment choices.
EUV may still have its day but even without it the industry appears to be positioning itself to move forward.
The problems are not only about lithography but much more for example planarization, multiple masks, metrology etc. What i have seen, the cost will increase exponentially but the ROI will be only additive.
It is interesting to compare the history of DUV and EUV.
DUV resolution was improved first by increasing NA (even to >0.85, before immersion possible), then reducing wavelength (248 nm to 193 nm).
So the EUV community should be focusing on increasing NA and the next EUV wavelength (BEUV or 6.7 nm).
I don't what is the current status at SPIE, but if there is still reluctance or lack of consensus to go to higher NA or BEUV, that's already a sign. Even going to NA>0.4 requires re-consideration of the EUV multilayer design which affects the lithography demagnification and the mask infrastructure.
Then the irony will be that the EUV community could begin to support double patterning, triple patterning, etc. at 13.5 nm. Which defeats the current justification to going to EUV. We might be hearing about this next year, in preparation for 7 nm node.
We should look beyound the lithography tool solutions. We should modify the design rule and make relatively simple chips. I think we have already missed the deadline on 7nm EUV with the current source power.
Rick, the only viable option right now is multi-patterning solution. Ofcourse the cost will be very high and the challenges immense but some top level executive would want to make it a marketing sucess.