This invention relates to a dual inlaying structure including a base, a dielectric layer, a metal hard mask layer, a protection layer and a conduction layer, in which, the base includes a conduction region, the dielectric layer is matched on the base, the metal hard mask layer is matched on the dielectric layer, the protection layer is matched on the metal hard mask layer, in which, the protection layer, the metal hard mask layer and part of the dielectric layer have grooves and an open-end is in the dielectric layer under the groove exposing the conduction region, apart from that, the conduction layer is matched in the grooves and the open-end. |