A semiconductor device includes a substrate, a bottom sublayer having a monoatomic layer thickness, disposed on the substrate, located at a bottom of the device, and extending in a horizontal direction, a metal sublayer having a monoatomic layer thickness, overlaying the bottom sublayer in the horizontal direction and electrically connected to the bottom sublayer, a top sublayer having a monoatomic layer thickness, disposed in the horizontal direction and electrically connected to the metal sublayer, and a contact metal layer disposed above the metal sublayer. A top surface of the contact metal layer is higher than a top surface of the top sublayer. Bottom layer contact metal atoms of the contact metal layer directly form corresponding bonds with a metal atom surface of the metal sublayer exposed after a portion of the top sublayer is stripped. Original corresponding bonds are maintained between the metal sublayer and the bottom sublayer. |