Taiwan’s Commonwealth Magazine (天下雜誌) put out an excellent two-part article on November 25, 2019, detailing the state of TSMC’s 7 nm+ process using EUV.
Part 1, here.
Part 2, here.
It is well worth the effort to read this series carefully. It went over how TSMC has came to dominate the race to manufacture ever more complex semiconductors, and how it beat Intel and Samsung to volume production of chips using EUV.
What I find most interesting is this following quote:
“TSMC has taken a different approach. It discovered by surprise that by using a special dust-prevention design for the mask package, it could achieve a certain yield rate without the need for a pellicle.”
Pellicle is an ultrathin membrane about 50 nm, used to keep tiny specks of dust away from “mask blanks”. “This protective cover is extremely hard to produce because it challenges physical extremes. They have to be thin enough to remain transparent but strong enough to resist the intense heat of EUV radiation blasts, which can reach hundreds of degrees.”
Both Intel and Samsung have struggled with their pellicles, yet TSMC has apparently found a way to proceed without pellicles and was able to move ahead on volume production using their N7+ process!
How does TSMC ensure an ultra clean room, and ensure a super clean environment for their mask blanks, without the protection of pellicles?
It appears that TSMC will not be using pellicles for both their 7 nm+ and the upcoming 5 nm processes. They will use their own pellicles for the futuristic 3 nm process.
This is all very amazing, considering that Intel has struggled mightily with their 10 nm (well documented), and their 7 nm is not guaranteed yet.
In retrospect, it was great that Global Foundry dropped out of the 7 nm race, and AMD was able to have all their 7 nm chips made by TSMC.
AMD has found a super partner and the pace of innovation is relentless. AMD will have chips made with 7 nm+ and soon 5 nm processes.
Finally, the following quote is also extremely interesting.
[“TSMC indirectly serves China’s People’s Liberation Army (PLA) and the U.S. Department of Defense with chips used in cruise missiles, military drones, and submarines. An executive at a semiconductor company in which Intel previously held a stake describes TSMC as the “guardian factory protecting the country.”
“Do you think China would really dare attack Taiwan? Many of the chips the PLA uses are made by TSMC,” he says.]
Recently US had asked TSMC to make chips in US to ensure Americans’ national interest. TSMC politely declined. It’s quite revealing when TSMC itself talks about its own geopolitical importance.