How China’s award-winning EUV breakthrough sidesteps US chip ban
The research team took a completely different technological approach from Western methods to generate EUV laser light.
According to the institute’s website, the “discharge plasma extreme ultraviolet lithography light source” project, led by Professor Zhao Yongpeng from the school of aerospace engineering, “boasts high energy conversion efficiency, low cost, compact size and relatively low technical difficulty”. “It can produce extreme ultraviolet light with a central wavelength of 13.5 nanometres, meeting the urgent demand for EUV light sources in the photolithography market,” an official report said.
Zhao’s team, on the other hand, uses the laser-induced discharge plasma (LDP) method, where a laser first vaporises a small amount of tin into a cloud between two electrodes. A high voltage is then applied across the electrodes to inject energy, converting the tin cloud into plasma.
The resulting electrons and high-valence tin ions frequently collide and radiate, generating EUV light.
Compared with LPP technology, the LDP method is simpler, more cost-effective and directly converts electrical energy into plasma with higher energy utilisation efficiency.