Patent ID: 8530749

Claim:
An ultra-thin copper foil to which a carrier foil is attached, comprising: a carrier foil, a peeling layer, and an ultra-thin copper foil, wherein the peeling layer comprises a first metal A having peelability, and a second metal B and a third metal C facilitating coating of the first metal, wherein the amount (a) of the first metal A is in a range of about 30 to about 89% by total weight of the peeling layer, the amount (b) of the second metal B is in a range of about 10 to about 60% by total weight of the peeling layer, and the amount (c) of the third metal C is in a range of about 1 to about 20% by total weight of the peeling layer, wherein the second metal B and the third metal C are different from each other, wherein the first metal comprises Mo or W, and the second metal and the third metal are each independently one selected from a group consisting of Fe, Co, and Ni, wherein the second metal and the third metal are different from each other.