PREVIOUS LAYER SELF-ALIGNED VIA AND PLUG PATTERNING FOR BACK END OF LINE (BEOL) INTERCONNECTS

摘要

Previous layer self-aligned via and plug patterning for back end of line (BEOL) interconnects are described. In an example, an interconnect structure for an integrated circuit includes a first layer disposed above a substrate. The first layer of the interconnect structure includes a grating of alternating metal lines and dielectric lines in a first direction. A second layer of the interconnect structure is disposed above the first layer. The second layer includes a grating of alternating metal lines and dielectric lines in a second direction, perpendicular to the first direction. Each metal line of the grating of the second layer is disposed on a recessed dielectric line composed of alternating distinct regions of a first dielectric material and a second dielectric material corresponding to the alternating metal lines and dielectric lines of the first layer of the interconnect structure.