Using a Novel Solvent-based Technology to Preserve Low-k Material when Removing Gap Fill Material

Abstract

As the technology nodes shrink, device makers are running into barriers with traditional post etch process flows. In the back-end-of-line (BEOL), the porous low-k materials can be damaged by the etch chemistries, the dry ash plasmas and the subsequent cleaning processes. Replacing the dry ash and typical wet cleaning processes with a one step selective solvent-based removal process can work to protect the etched low-k. The solvent-based blend must remove the reactive ion etch (RIE) residues and gap fill material used in the patterning step while preserving the low-κ from further damage. This paper will focus on the removal of films and post etch residues in under 2 minutes with a novel solvent formulation.