The method of manufacturing a semiconductor device includes a first conductor over a semiconductor substrate; forming a first insulator over the first conductor; forming a second insulator, having an etching characteristic different from an etching characteristic of the first insulator, over the first insulator; forming a second conductor on the second insulator, the second conductor being in contact with the second insulator; forming a third insulator, having an etching characteristic different from the etching characteristic of the second insulator, over the second conductor; forming a first contact hole though the third insulator and the second conductor, the first contact hole exposing the second insulator; forming a second contact hole through the third insulator and the first insulator, the second contact hole exposing the first conductor; forming a third conductor in the first contact hole, wherein a side wall of the third conductor is electrically connected to a side wall of the second conductor; forming a fourth conductor in the second contact hole, wherein the fourth conductor is electrically connected to the first conductor.