The invention relates to the technical field of
copper foils, in particular to a composite layer carrier
copper foil, a preparation method of the composite layer carrier
copper foil, a method for easily stripping an ultrathin
copper foil with a carrier from a composite layer, the ultrathin
copper foil and a preparation method of the ultrathin
copper foil. The composite layer comprises a
nickel layer and an
organic layer of a
tetrazole compound from inside to outside, and the
tetrazole compound has a structure as shown in the following formula (1): R1 is selected from
hydrogen, amino, a
tetrazole group or a group containing 1-5 carbon atoms; r1 is selected from
hydrogen, sulfydryl, amino or a group containing 1-5 carbon atoms, R2 is selected from
hydrogen, sulfydryl, amino or a group containing 1-5 carbon atoms, and the groups containing 1-5 carbon atoms in R1 and R2 are respectively selected from C1-C5
alkyl groups, carboxyl-substituted C1-C5
alkyl groups and sulfenyl-substituted C1-C5
alkyl groups. The composite layer carrier copper foil provided by the invention has the characteristics of easy stripping and stable stripping performance.