A method for the production of airgaps in a semiconductor device and
device produced therefrom. The formation of airgaps is accomplished, in
part, by chemically and/or mechanically changing the properties of a
first dielectric layer locally, such that at least part of said first
dielectric layer is converted locally and becomes etchable by a first
etching substance. The local conversion of the dielectric material may be
achieved during anisotropic etching of the material in oxygen containing
plasma or ex-situ by performing an oxidizing step (e.g., a UV/ozone
treatment or supercritical carbon dioxide with addition of an oxidizer).
Formation of airgaps is achieved after creation of conductive lines and,
alternatively, a barrier layer by a first etching substance. The airgaps
are formed in a dual damascene structure, near the vias and/or the
trenches of the damascene structure.