1 OZ Copper PCB is basic thickness for Printed Circuit boards, Special for Rigid pcb Board, Enough copper can ensure the PCB board working well,When your design request 1 copper , Pls make sure it is enough 35 Micron (1 oz) .
1 oz copper (~35µm thick or 1.4 mils) — Standard internal layer copper thickness for “standard construction product for 1 oz and 2 oz finished copper weight selections. This is also the standard starting copper weight on the external layers for PCBs with the 2 oz finished copper weight selection.
General Guideline for Min Spacing by Copper Weight
Cu Weight Min Recommended Space between Copper Feature
1 OZ 3.5 mil (0.089 mm)