A semiconductor device includes a substrate, a first dielectric layer on the substrate, a hard mask layer on the first dielectric layer, a trench in the hard mask layer and the first dielectric layer, a first source/drain electrode layer on a sidewall of the trench, a second dielectric layer on the first source/drain electrode layer in the trench, a second source/drain electrode layer on the second dielectric layer in the trench, a third dielectric layer on the second source/drain electrode layer in the trench, an ILD layer overlying the trench, an nFET disposed over the trench, and a pFET disposed over the trench and spaced apart from the nFET.