Method for measuring surface parameter of copper foil, method for sorting copper foil, and method for producing surface-treated copper foil

Abstract

A method for measuring a surface parameter of copper foil exhibiting high correlation with high frequency characteristics, the method for measuring a surface parameter of copper foil including: (a) acquiring a surface profile on at least one surface of an untreated copper foil; (b) setting a cutoff value for an L filter based on the surface profile; (c) acquiring a surface profile on at least one surface of surface-treated copper foil originating from the untreated copper foil; (d) subjecting the surface profile of the surface-treated copper foil to filter processing, the filter processing including processing using an L filter with the cutoff value; and (e) calculating at least one of surface parameters defined by ISO25178 on the surface of the surface-treated copper foil based on the surface profile after the filter processing.

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