I was wondering if there is any way to create a board with 2 layers, but the layers have different shapes. I have a small silicon sensor and I basically want it to sit flush in a cutout in the top layer. Is this possible here, or anywhere for that matter?
You could make two boards, and glue/screw them together.
You definitely can’t do it on a 4 layer process, but what we’ve done before is made two boards with matching pads on each side and reflowed them together. Works great + you get electrical connectivity all the way through the design.
You would have to use different temp solder pastes though, one for the two boards / one for the components on the boards. [so it doesn’t fall apart mid assembly.
Cheers,
–David Carne