Formation of sub-100 nm contact hole patterns using a novel resist material

Flow process using a novel resist called the SMART (Samsung Advanced Resist for Thermal flow process) was studied. The SMART consisted of conventional polyhydroxy styrene-based polymers and the additives for cross-linking reactions with base polymers. When the SMART was used, 240 nm contact hole patterns were reduced to 90 nm final patterns without much pattern deformation. At 90 nm resolution, the critical dimension (CD) uniformity on 200 mm wafer was less than 20 nm. The etching selectivity of resist to silicon oxide was increased due to the cross-linking reaction. Based on these results, the flow process by the SMART is a very promising candidate for the fabrication of gigabit devices.