A semiconductor device is provided, which is capable of miniaturization to a level corresponding to 1-Gb DRAMs. A first interlayer insulating layer is formed on or over a semiconductor substrate to cover a first-level conductive layer. First and second conductive sublayers of a second-level conductive layer are formed on the first interlayer insulating layer. First and second insulating caps are formed on the first and second sublayers, respectively. A lower contact hole penetrating the first insulating layer is formed to be self-aligned with the first and second sublayers. A conductive pad is formed on the first-level conductive layer in the lower contact hole to be electrically insulated from the first and second sublayers by an insulating spacer. A second interlayer insulating layer with an upper contact hole communicating with the lower contact hole is formed on the first interlayer insulating layer. A third-level conductive layer is formed on the second interlayer insulating layer to be contacted with the conductive pad through the upper contact hole.