OPC model accuracy of dry resist readiness for 0.55NA EUVL by using low-n bright field mask (Invited Paper)

As High Numerical Aperture Extreme Ultraviolet Lithography (0.55NA EUVL) gets ready to step in the integrated circuit manufacturing world, advanced materials and patterning becomes very critical in terms of resolution, roughness, defectivity and process window. Among various combinations of mask absorber materials, mask tones and process, bright field (BF) mask with utilization of negative-tone metal oxide resists (MORs) have become one of the most promising candidates for 0.55NA EUVL patterning. Lam Research has extended the potential of MORs by developing a novel flow that consists of dry resist deposition and dry resist development [1]. The new process brings advantages and specificities that shows promising patterning performance on 0.55NA EUVL, which will impact on the OPC flow. Therefore, in this paper, we will investigate the Calibre OPC model accuracy of dry resist process by using low-n attenuated phase-shift BF mask. The use case is conducted on imec N2 (pitch 28nm) metal design, and the wafer will be exposed by using imec NXE 3400 scanner. Thousands of OPC-relevant features are selected, and all the SEM images (after develop inspection and after etch inspection) are ac