Process Options for Copper Circuit Manufacture

摘要

Additive, semi-additive, semi-subtractive, sub-tractive.... Whether they are rigid or flexible, this is the basic shopping list of methods for creating copper circuits for printed circuits. While previous columns have touched on the different types of copper foil used to produce flex circuits (e.g. wrought foil versus plated foil) and discussed their relative merits, the methods of circuit creation using the different offerings is an interesting subject that is worthy of review. Of the four choices given above, the first and last options are fairly self-explanatory. However, one might rightfully ask if there is any difference between semi-additive and semi-subtractive, or are they one and the same? A review of the different methods should help to answer the question.