Methods of producing integrated circuits with an air gap

A method of producing an integrated circuit comprising:

• forming an interconnect trench in a dielectric layer, wherein the interconnect trench comprises an interconnect trench bottom;
• forming a conformal barrier layer overlying the dielectric layer and within the interconnect trench;
• forming a barrier spacer by removing the conformal barrier layer from the interconnect trench bottom such that the dielectric layer contacts the barrier spacer at an interconnect trench side wall;
• forming an interconnect within the interconnect trench after forming the barrier spacer such that the same dielectric layer that contacts the barrier spacer contacts the interconnect at the interconnect trench bottom;
• forming an air gap trench in the dielectric layer adjacent to the barrier spacer;
• and
• forming a top cap overlying the interconnect and the air gap trench, wherein the top cap bridges the air gap trench to produce an air gap in the air gap trench.