專利摘要：
A yellow light photolithographic process and an electroplating process are performed multiple times to produce copper plated layers on the aluminum nitride (AlN) substrate. The copper plated layers are plated in sequence into a stack structure with each layer having reduced length. The parameters of the yellow light photolithographic process can be adjusted, such that each copper plated layer is formed horizontally for a predetermined length into a stack structure of step layers tapering off upward, while a predetermined angle is formed by the tangent line passing through edges of the respective step layers, and the surface of the AlN substrate. An adhesion layer, a copper seed layer, a first copper plated layer, a second copper plated layer, a third copper plated layer, and a nickel plated layer are formed in sequence on the AlN substrate, to form a metalized circuit of multi-layer stack.