This project started with a phone call several months ago from a Canadian government lab. They had a very specific application so the design was driven much more by their requirements than most zero-background holder designs. A 1mm deep well with a zero-background plate at the bottom was a key specification. We tried several options for creating this, but settled on a two-part design with a solid “floor” plate and a ring above it. As it turns out, cutting a ring out of monocrystalline Si was more challenging than I’d expected.

It took a few months of experimenting with various fixtures to settle on a design that had a low failure rate and excellent cut quality, but with that done, the sample holders came out beautifully. Making these with a traditional, solid, plate would certainly be much easier, but this kind of project is always an opportunity to try something new.