US Patent 11676854 Selective ILD deposition for fully aligned via with airgap

A method is presented forming a fully-aligned via (FAV) and airgaps within a semiconductor device. The method includes forming a plurality of copper (Cu) trenches within an insulating layer, forming a plurality of ILD regions over exposed portions of the insulating layer, selectively removing a first section of the ILD regions in an airgap region, and maintaining a second section of the ILD regions in a non-airgap region. The method further includes forming airgaps in the airgap region and forming a via in the non-airgap region contacting a Cu trench of the plurality of Cu trenches.