The US is considering stepping up a ban on the export of chipmaking equipment to China by including advanced 128-layer memory chip-related equipment, Reuters reported on Tuesday, citing unnamed sources from two leading US-based chip firms, Research Corp and Applied Materials. The ban under discussion would not only affect Chinese firms such as YMTC but would also damage overseas companies that operate factories in mainland China such as Samsung and SK Hynix, the sources said. The report notes that discussions are still in the early stages and that no draft regulations have yet been filed. Last month, the US tightened restrictions on China’s access to equipment for the production of chips more advanced than 14nm as it looks to contain the country’s semiconductor industry. [Reuters]