US Patent 11361967 Underlayers for EUV lithography

New lithographic compositions for use as EUV silicon hardmask layers are provided. The present invention provides methods of fabricating microelectronic structures and the resulting structures formed thereby using EUV lithographic processes. The method involves utilizing a silicon hardmask layer immediately below the photoresist layer. The silicon hardmask layer can either be directly applied to the substrate, or it can be applied to any intermediate layer(s) that may be applied to the substrate. The preferred silicon hardmask layers are formed from spin-coatable, polymeric compositions. The inventive method improves adhesion and reduces or eliminates pattern collapse issues.