Interconnection structure and manufacturing method thereof

The invention discloses an interconnection structure and a manufacturing method thereof. The interconnection structure comprises a first interlayer dielectric layer, a first lead, a protective layer, a second interlayer dielectric layer and a connecting plug. The first wire portion is disposed in the first interlayer dielectric layer. The protection layer is arranged on the first lead and the first interlayer dielectric layer. The protective layer covers the upper surface and the side wall of the first wire. The protection layer is provided with a recess corresponding to the first wire in the vertical direction. The second interlayer dielectric layer is disposed on the protective layer. The connecting plug penetrates through at least one part of the second interlayer dielectric layer and the protection layer and is used for being connected with the first wire. 本发明公开一种互连结构以及其制作方法，其中该互连结构包括第一层间介电层、第一导线、保护层、第二层间介电层与连接插塞。第一导线部分设置于第一层间介电层中。保护层设置于第一导线以及第一层间介电层上。保护层覆盖第一导线的上表面与侧壁。保护层具有凹陷于垂直方向上与第一导线对应设置。第二层间介电层设置于保护层上