Forming air gap

Abstract

A method of forming an air gap for a semiconductor device and the device formed are disclosed. The method may include forming conductive interconnects in an ILD including a high etch selectivity dielectric layer such as a silicon nitride with hydrogen component (SiNH) layer, and patterning an air gap mask layer preferably using extreme ultraviolet (EUV) light form an air gap mask. The air gap mask may be used to etch an air gap space in the high etch selectivity dielectric layer. Use of EUV with the high etch selectivity dielectric layer provides an air gap having a width of no greater than 15 nm with the opening used to form the air gap space having a width of no greater than 10 nm width. This integration approach offers smaller pinch-off height, e.g., less than approximately 6 nm, which improves process window for subsequent Mx+1 module builds.

Dependencies are inferred from the claim text.