The mystery of ASML’s wafer stage

To this day, the electric table, the superior alignment technology and Zeiss’ lenses and EUV mirror optics are ASML’s technological bedrock. Its super-fast, super-precise stage and alignment have been unique selling points for decades, the reasons why chipmakers buy the Dutch lithography machines. The electric table makes ASML’s steppers the most productive in the world, and the alignment system ensures that despite that high speed, everything runs at ultra-precision.

This makes it all the more remarkable that the joint-venture deal between ASM and Philips in 1984 didn’t include the electric table. Instead, the deal was based on the PAS 2000 wafer stepper, which was unsellable due to its oil-based drive system. Why did Philips’ engineers cling to the old technology for so long, while the electric stage was available as a prototype at Philips’ Natuurkundig Laboratorium (Natlab)? That may be the greatest mystery from ASML’s early days. The seventeen hydraulic clunkers that were transferred to Veldhoven were in fact white elephants – and Philips S&I knew that. ASM was being taken for a ride, but to be fair, it didn’t inspect the deal closely enough, either.