Low-NA EUV extension technology of contact patterning using MOR process

For the development of next-generation DRAM devices, innovative lithographic materials and process that can help the extension of EUV SET are crucial. Also in order to extend Low NA EUV SET, new technologies of contact patterning are required. Especially innovative processes such as MORs or dry development are currently being evaluated for mass production in L/S or pillar patterns, whereas there is currently no alternative for contact patterning. For hexagonal contact patterning with a pitch of 30nm or less, we achieved remarkable optical performance improvement by changing the reticle tone from dark tone to bright tone and optimizing SMO. Since the reticle tone is a bright tone, the NTD process is required for contact patterning on the wafer, and by introducing the MOR process, we can secure a process with excellent EUV absorption rate and resolution, as well as superior etch resistance to EUV.