LITHO-LITHO ETCH (LLE) DOUBLE PATTERNING METHODS

摘要

Litho-litho-etch double patterning (LLE-DP) methods using silylation freeze technology are presented. The LLE-DP method using a silylation freeze reaction comprises providing a substrate with a first photoresist layer thereon. A first exposure process is performed defining a first latent image in a first photoresist. The first patterned structures on the substrate is developed and baked for photo-generated acid diffusion. The photo-generated acid is reacted with a silylation agent to freeze the first patterned structures. A second photoresist layer is formed overlying the substrate. A second lithography process is performed to create second patterned structures on the substrate. The first patterned structures and the second patterned structures are interlaced each other.