Semiconductor device including interconnection structure

Abstract

A semiconductor device includes a lower structure; an intermediate insulating structure on the lower structure; an intermediate interconnection structure penetrating through the intermediate insulating structure; an upper insulating structure on the intermediate insulating structure and the intermediate interconnection structure; and an upper conductive pattern penetrating through the upper insulating structure and electrically connected to the intermediate interconnection structure, wherein the intermediate insulating structure includes an intermediate etch-stop layer and an intermediate insulating layer thereon, the intermediate insulating layer includes first and second intermediate material layers, the second intermediate material layer having an upper surface coplanar with an upper surface of the first intermediate material layer, the intermediate interconnection structure penetrates through the first intermediate material layer and the intermediate etch-stop layer, and a material of the first intermediate material layer has a dielectric constant that is higher than a dielectric constant of a material of the second intermediate material layer.