Step Copper PCB Circuit Boards With External layers has a Combination of the standard(4OZ) and Heavy /EXTREME(30oz) Copper

PCB boards Spec:

Board size:20*5CM

Material:Fr4

Special:Heavy copper

Copper weight:4OZ and 30OZ

Questions:

1. what is the maximum copper weight that you can cater?

30OZ
2. Are there special notes that should be declared on the FAB note instructions? (e.g. minimum trace width, minimum spacing… etc.)

If this heavy copper ,min trace width and space is 10OZ   25MIL   20OZ  50MIL  30OZ  80MIL

> external layers has a combination of the standard and Heavy /EXTREME Copper.

See sample pic showing 2oz, 10oz, 20oz & 30oz

Can this be done??

Yes,this can be done

4. Is via stitching applicable?

Yes,but must enough big
5. Minimum layer stack-up?

Over 10OZ 1 layer and 2 layer more