By Nathan Vifflin

AMSTERDAM, May 27 (Reuters) - Taiwan Semiconductor Manufacturing Co (2330.TW), the world's largest contract chipmaker, is still assessing when it will use ASML's cutting-edge high numerical aperture $(NA)$ machines for its future process nodes, an executive said on Tuesday.

Chipmakers are weighing when the speed and accuracy benefits of these nearly $400 million machines will outweigh the almost doubled price tag of what is already the most expensive piece of equipment in a chip fabrication plant.

Asked if TSMC plans to use the machine for its upcoming A14, and enhanced versions of the future node, Kevin Zhang said the company hasn't yet found a compelling reason.

"A14, the enhancement I talk about, is very substantial without using High-NA. So our technology team continues to find a way to extend the life of current (Low-NA EUV machines) by harvesting the scaling benefit," he said at a press briefing.

"As long as they continue to find a way, obviously we don't have to use it," Zhang said.

Rival Intel INTC.O has planned to use the High-NA EUV machine in its future manufacturing process, known as 14A, in an attempt to revive its contract chip business and better compete with TSMC.

However, Intel also says that customers will still have the option of using older and more proven technologies.

During ASML's last earnings report, CEO Christophe Fouquet said he expects customers to test High-NA for high-volume manufacturing readiness through 2026-2027, before they evaluate the tool on their most advanced nodes in a latter phase.

Last year, Zhang had told reporters TSMC will not use High-NA for its A16 node, adding he did not like the sticker price.

So far, ASML has shipped five of the 180 ton, double-decker sized machine across the world to three customers, counting Intel, TSMC and Samsung 005930.KS.

(Reporting by Nathan Vifflin in Amsterdam; Editing by David Holmes)

((nathan.vifflin@thomsonreuters.com; +48 58 769 67 13;))