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They made metallic glass nanotubes with an average wall thickness of just 20nm, and fabricated nanosheets from different substrates, such as sodium chloride, polyvinyl alcohol and conventional photoresist substrates, with different levels of oxygen concentration.

They use a 3D printing approach known as two-photon polymerization, which focuses an infrared laser into a UV sensitive photoresist.

The companies Nishikawa worries about include wafer makers Shin-Etsu Chemical and Sumco Corp photoresist supplier JSR Corp and production machinery builders Screen Holdings and Tokyo Electron.

“We are always prepared to respond to policy changes in each country,” said a spokesperson for JSR, which makes light sensitive photoresist coatings used for engraving chips in Japan, Belgium and the United States.

It will take time to localise high-tech materials like EUV photoresist, former Hynix engineer Kim Sang-yong said.