US officials are now concerned that geopolitical tensions could escalate, negatively impacting the supply of cutting-edge semiconductors. ASML has promised the government it can remotely “shut down” the plant if a threat arises.

The remote disable feature is available on extreme ultraviolet machines, also known as EUV, made by Dutch company ASML, of which TSMC is one of its biggest customers.

EUV uses high-frequency light waves to print transistors, used on the smallest microchips available, to create chips for artificial intelligence applications or military use.

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ASML's EUV machines can be "disabled" remotely. Photo: SCMP

About the size of a city bus, the EUVs cost more than $217 million each and require regular maintenance and updates. The company has integrated a remote “off button” into the devices, which are manufactured exclusively by ASML, the people said.

The Dutch company has long been subject to government interference in EUV export controls to countries such as China. At Washington’s request, the Netherlands stopped selling ASML’s next-generation chip foundry machines starting this year. The Veldhoven-based company has even had to cancel some previously scheduled orders.

ASML has shipped more than 200 of these machines to customers outside China since the first generation in 2016, with TSMC buying more than any other chipmaker. About 90% of the world's most advanced chips are now made in Taiwan.

The EUV machine has helped turn ASML into Europe's most valuable tech stock with a market capitalization of $370 billion, double that of Intel.

Meanwhile, on-site EUV maintenance poses a challenge because they are housed in clean rooms, requiring engineers to wear special suits to avoid contamination.

ASML provides some customers with regular maintenance contracts, such as allowing TSMC to access its own machine systems. The foundry company said it cannot access customers' proprietary data.

The company expects about 15% of its sales to China this year to be affected by the latest export controls.

ASML's China sales expected to fall 10-15% due to sanctions Foundry equipment maker ASML said that export restrictions from the US and the Netherlands will cause its sales in China to fall by 10-15%, after hitting a record last year.