[gnramires]

That would work only for a planar distribution of material. A 3D distribution would require multiple layers (I guess it might quickly become infeasible if it requires thousands of layers).

In the case of 3D arrangements, I think some substrate materials (and also some properties of the particles) would be very difficult to get using photolithography (or some kind of micro 3D printing).

[kuschku]

In the case of 3D arrangements, you don't necessarily need to create all the layers photolithographically. You might be able to flatten N layers into 1 layer, then add a plastic coating equivalent to N-1 layers ontop, then repeat that. You'll have a very similar result to every layer being separate.

Imagine e.g. the "multiple layers of cardboard cutouts" scenery in theater vs it actually being 3D.