Dual damascene aperture formation method absent intermediate etch stop layer

摘要

Within a method for forming a dual damascene aperture there is surface treated a first dielectric layer to form a surface treated first dielectric layer having a first surface composition different than a first bulk composition. There is then formed upon the surface treated first dielectric layer a second dielectric layer having a second bulk composition. Finally, there is then formed through the second dielectric layer a trench contiguous with and overlapping a via formed through the surface treated first dielectric layer. Within the present invention, when forming the trench through the second dielectric layer an endpoint is determined by detecting a difference between the second bulk composition and the first surface composition.