Thin Underlayer Materials for Metal Oxide Resist Patterning

We introduce thin underlayer (UL) materials (<10 nm) for metal oxide resist (MOR) that can support the lithography performance requirements as well as compatible with conventional etching tool and etching process. Thin UL materials for MOR patterning applications required to have chemical moieties with specific functions and excellent physical properties to meet both lithography and etching performance requirements. We investigated the relationship between surface properties of thin UL materials and its effects on MOR sensitivity, pattern collapse, and defects. We also discussed plausible mechanism based on our experimental results. In addition, we have also confirmed the impact of high EUV absorption unit effect in UL materials on MOR sensitivity.