Western anxiety over a potential breakthrough in Chinese chipmaking gear may be rising, but home-grown machines are not the greatest threat facing industry leader ASML, according to analysts.The Dutch firm’s shares fell more than 8 per cent at one point on Monday in the US before closing down 5.8 per cent, after The Information reported that China had begun manufacturing home-grown immersion deep-ultraviolet (DUV) lithography machines through a state-backed company in Shanghai.China would produce about five DUV units this year and around 20 in 2027, The Information reported, citing anonymous sources. The first systems were expected to go to Semiconductor Manufacturing International Corporation (SMIC), Hua Hong Semiconductor and memory-chipmaker ChangXin Memory Technologies (CXMT), the report said.While the news fuelled a rally in lithography-related shares in mainland markets on Tuesday – sending Zhangjiang Hi-Tech, Yongxin Optics, Highly Group and Wavelength Opto-Electronic to their daily limits – industry observers urged caution over the reported advance.Delivering a domestic machine was not the same as qualifying it for continuous commercial production, said Paul Triolo, partner and technology policy lead at DGA-Albright Stonebridge Group.“Producing machines of the complexity of DUV immersion lithography that are commercially viable and running 24 hours, seven days a week, for an entire year is very difficult,” he said.