Seminar series

10-11am, March 24, 2026  Zoom

Amorphous Zeolitic Imidazolate Frameworks (aZIF) as Resists for EUV and BEUV Lithography

Advancements in lithography have focused on shorter exposure wavelengths and new resist types to enable finer feature patterning, resulting in denser integrated circuits and more efficient chips. However, current resist technologies may not meet future demands outlined in technology roadmaps for sub-nanometer nodes, which target features down to 5 nm and below. We introduced a class of amorphous metal organic frameworks (amorphous zeolitic imidazolate frameworks: aZIFs) as resists for electron-beam lithography (EBL), extreme ultraviolet lithography (EUVL: 13.5 nm), as well as for lithography using smaller wavelengths, beyond EUV (BEUV: 6.7 nm). The sensitivity and tone (negative or positive) of aZIFs can be tuned by the choice of metal and imidazole, and by the selection of appropriate vapor or liquid development methods. aZIF resists can be deposited by ALD/MLD, as well as by spin-on methods, with excellent control of compositions, thickness, and wafer-scale uniformity.
In this talk, I will give a historical perspective of ZIFs starting from Professor Yaghi’s group discoveries that established this class of materials, describe their solvothermal and vapor phase synthesis, their solubility in aqueous solvents, and their sensitivity to low energy electrons, which led us to propose them as lithographic materials (Angew. Chem. Int. Ed. 57, 13592-13597 (2018)). The current status of development of aZIF resists will then be described based on our recently published work (Chemistry of Materials 37(21), 8548–8567 (2025), Nature Chemical Engineering 2, 594-607 (2025)), followed by a description of our ongoing efforts to exploit the rich compositional space of a ZIFs to improve their sensitivity and resolution.