ASML’s road to 1000-watt EUV source power

Remember the EUV light source? Ten years ago, tech media talked about little else. The stalled development of an industrial-grade source with sufficient power output was by far the main reason that EUV lithography wasn’t introduced into production around 2010, as was the original intention, but almost a decade later. “The source is obviously not a great story, and it probably won’t be for the time being,” former ASML CTO Martin van den Brink let slip in 2011 (see Bits&Chips 11, 2011). At the time, his employees had to slog away another six years or so before ASML’s customers started believing in EUV.

The first production source delivered about 250 watts of EUV light, enough to process about 125 wafers per hour (the more light hitting a wafer, the faster a single exposure and hence the more wafers per hour). With an availability of around 90 percent, EUV tools were still down for considerably longer than chipmakers were used to, but in 2018, both Samsung and TSMC found productivity to be satisfactory. The first smartphone with an EUV chip hit the shelves a year later.