A method for forming a semiconductor device structure is provided. The method includes forming a first dielectric layer over a first substrate, and the dielectric layer has a plurality of openings. The method also includes forming a first graphene layer in the openings and over the first dielectric layer, and forming an insulating layer in the first graphene layer. The method further includes forming a second dielectric layer over the first dielectric layer and forming a second graphene layer in and over the second dielectric layer. A portion of the second graphene layer interfaces with a portion of the first graphene layer.