Computer chips are created using photolithography. Today's lithography machines are highly complex machines containing ultra-high precision optics. How do you create and in particular measure these optics? That's easy, you build the world's best interferometer. But what if that's not enough?
Structures on computer chips are getting smaller and smaller. To be able to print these nanometer-sized structures correctly, the surfaces of the used lithography optics have to be manufactured to sub-nanometer precision. We have now reached technical limits on how exactly one can measure these. This talk explains how we can get beyond that.
Measurement precision and accuracy is all about separting the desired signal from any background. When all technical and signal processing techniques are exhausted, the only chance left is to know your background exactly. If you know everything about your measurement machine, you can calculate your background and thus separate signal from backgound. This talk describes how we at Carl Zeiss build complex simulations of our high-end measurement machines to enable the next generations of computer chips.