A selective wet etching process is used, prior to air gap opening formation, to remove a sacrificial nitride layer from over a first region of an interconnect dielectric material containing a plurality of first conductive metal structures utilizing a titanium nitride hard mask portion located over a second region of the interconnect dielectric material as an etch mask. The titanium nitride hard mask portion located over the second region of the interconnect dielectric material is thereafter removed, again prior to air gap opening formation, utilizing another wet etch process. The wet etching processes are used instead of reactive ion etching.