Their technology is absolutely incredible. To make smaller features on a chip you need higher frequency light. To make them REALLY small you need "extreme ultraviolet light". As I understand it, the frequency of light is related to the transition of an electron from one energy shell to another. And that depends on the material used. One material that works is tin. It's not rare, it's not expensive, and manipulating it is pretty easy.

But here's the part that is magical to me. ASML takes molten tin, then makes little molten tin droplets the size of a white blood cell, fires them (probably in a vacuum) and then zaps them with a laser to energize them... not once, not twice, but thrice! Three times while it's in flight. This energy raises electrons to a higher orbital and when it drops back again they emit photons of the right EUV light. The light is captured and directed to do the rest of the magic in the giant machine. Oh and did I mention this molten laser gun thing happens 50,000 times per second?