The present disclosure provides a method for fabricating an integrated circuit. The method includes forming an energy removable film (ERF) on a substrate; forming a first dielectric layer on the ERF; patterning the ERF and first dielectric layer to form a trench in the ERF and the first dielectric layer; filling a conductive material in the trench; forming a ceiling layer on the first dielectric layer and conductive material filled in the trench; and applying energy to the ERF to form air gaps in the ERF after the forming of the ceiling layer.