Dual-layer Hybrid (Organic/Inorganic) Anti-Reflective Coating
Original Publication Date: 2002-Jul-08
Included in the Prior Art Database: 2002-Jul-08
Dual-layer anti-reflective coatings (ARCs) can provide much lower total reflectivity than any known single-layer ARC film, where the top layer functions in phase cancellation mode and the bottom layer in absorption mode. Further, the use of a hybrid dual-layer ARC, where the first layer deposited is inorganic in composition and the second layer organic, may be used to take advantage of an inherent etch/ash selectivity for films of different chemical composition. This inherent etch selectivity can be used to lower the total effective ARC thickness to be removed during subsequent RF sputter and CMP processing, thereby facilitating complete ARC removal. The use of a chemical vapor-deposited (CVD) organic layer may additionally serve to lessen total reflectivity in a dual-inlaid integration scheme, prevent negative interaction between exposed dielectric sidewall material and photoacid-catalyzed deep ultraviolet (DUV) photoresist, and potentially mitigate further etch/ash damage common to many low dielectric constant (low k) materials.