Several articles have mentioned the ability to do 7nm using 28nm resolution litho machine, and also members here have said similar things:
"The speed of lithograph procurement is a key signal of capital expenditure of the inner asset line. The inner asset line generally prioritizes the purchase of the value and the most technically difficult lithograph. From the yangtze River Storage, Huali micro, Huahong Wuxi, SMIC Shaoxing and Zhuzhou Zhongcar lithograph machine procurement situation, each production line 19Q4 to date the total optical machine procurement volume is considerable, foreshadowing its asset line capital expenditure in 2020 will be further enhanced.
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Although this 28nm photolithography machine is still a big gap with ASML’s current state-of-the-art 5nm EUV lithograph, it is of great significance to China’s semiconductor industry and Shanghai microelectronics itself, and even supports 7nm chips through multiple exposures.
As to ppl, there should be enough, considering that SMIC has its own N+1, N+2 tech, which they say could equal 7nm.?