Patent ID: 8674229
Filing Date: 2014-03-18
Classification: B32B,C22C,C25D,H05K,Y10T

Abstract:
1. An ultra-thin copper foil with a carrier comprised of a carrier foil, a release layer, and an ultra-thin copper foil, wherein the release layer is formed by a first release layer disposed on the carrier foil side and a second release layer disposed on the ultra-thin copper foil side, there are a first interface between the carrier foil and the first release layer, a second interface between the ultra-thin copper foil and the second release layer, and a third interface between the first release layer and the second release layer, the peeling strengths at the interfaces are such that first interface>third interface and second interface>third interface, when the thickness of the release layers remaining at the peeling surfaces on the carrier foil side and on the ultra-thin copper foil side when peeling the carrier foil from the ultra-thin copper foil are d the first release layer and the second release layer are formed by a metal A retaining a peeling property and a metal B facilitating plating of the ultra-thin copper foil, and an element ratio x of the metal A and an element ratio y of the metal B at the peeling surface on the ultra-thin copper foil side when peeling the carrier foil from the ultra-thin copper foil have a ratio of 10≦{(y/(x+y)}×100≦80(%).