The newer 2nm process can continue to utilize TSMC's existing EUV lithography tools for mass production and improved yields. However, as the Taiwanese semiconductor giant moves toward sub-2nm nodes, such as 1.4nm and 1nm (also known as the A14 and A10), it will face manufacturing hurdles. Currently, this problem can be easily solved by purchasing ASML's advanced high-numerical aperture EUV lithography tools, but a new report indicates that TSMC will no longer purchase ASML lithography tools and will instead turn to photomask pellicles.
EUV lithography machine
2nm wafer production is expected to be in full swing by the end of 2025, after which TSMC will eventually transition to the 1.4nm node. The company has laid the foundation for its move to advanced processes, with mass production expected to begin around 2028. With an initial investment of NT$1.5 trillion (approximately US$49 billion), TSMC is moving at lightning speed, launching 1.4nm process R&D at its Hsinchu fab and acquiring 30 EUV lithography machines.
However, one initiative TSMC has declined to pursue is the purchase of ASML's high-numerical-aperture EUV lithography machines, each priced at US$400 million. This equipment would ensure reliable production of 1.4nm and 1nm wafers with higher yields. The company may have determined that the equipment's value outweighed its actual value, and as a result, according to Dan Nystedt and the Commercial Times, TSMC is turning to photomask pellicles. The use of pellicles is essential for sub-2nm processes to prevent dust and other particles from contaminating the process.
Device Policy
Refuse to buy high NA and use protective film
Again, this is a costly move and comes with numerous complications. For example, using standard EUV machines to produce 1.4nm and 1nm wafers requires more exposures, meaning the photomask needs to be reapplied frequently to achieve success, potentially impacting yield. Protective films are also necessary during this stage to prevent the aforementioned dust particles and contaminants from entering the wafer fabrication process.
TSMC may persist with this approach, believing it is a worthwhile alternative to the $400 million investment per high-NA EUV lithography machine. Another drawback of high-NA EUV lithography machines is that ASML can only produce five to six per year, while TSMC is reportedly planning to purchase 30 standard EUV lithography machines to meet growing demand from numerous customers, including Apple. Therefore, spending a significant amount of money on a limited number of machines would undoubtedly be futile for TSMC's long-term goals.
Source: Content from the Commercial Times
