ABSTRACTThe need for an Anti-Reflection Coating (ARC) on aluminum metallizations is well known. A new class of materials based on tungsten-silicide and tungsten-silicon-nitride has been developed Tor use as an ARC. It has been shown that the reflectivity (relative to aluminum = 100%) can be decreased to −55% for the tungsten-silicide material and to −6% for the tungsten-silicon-nitride materials. These materials are easily etched in fluorine containing plasmas and are not as sensitive to thickness uniformity issues as dyed resists or amorphous silicon ARC materials. The option of leaving these ARC materials on the aluminum lines may lead to an increase in the electromigration resistance. The dependence of the reflectivity on nitrogen content has been investigated. Additionally, the reflectivity reducing properties have been studied on a variety of substrates such as aluminum, gold, tungsten, tantalum, and silicon.