Influence of Chemical\nStructures on E‑Beam\nLithography Performance of Polysilsesquioxanes

Hydrogenated silsesquioxane (HSQ) is a key inorganic\nelectron beam\nresist, celebrated for its sub-10 nm resolution and etching resistance,\nbut it faces challenges with stability and sensitivity. Our innovative\nstudy has comprehensively assessed the lithographic performance of\nthree functionalized polysilsesquioxane (PSQ) resist seriesolefins,\nhalogenated alkanes, and alkanesunder electron beam lithography\n(EBL). We discovered that the addition of olefin groups, such as in\nthe HMP-30 formulation with 30% propyl acrylate, remarkably increased\nthe sensitivity to 0.6 μC/cm<sup>2</sup>. The inclusion of halogenated\naromatic and hydrogen-substituted methyl groups further enhanced sensitivity\nand contrast, with HClBN-50 achieving a 22.9 nm resolution pattern.\nAt the same time, the storage of PSQ resists was significantly improved\ncompared to commercial HSQ with increasing alkane group content. Crucially,\nour research has unveiled the lithography reaction mechanism, highlighting\nhow group encapsulation and steric hindrance influence PSQ performance.\nThis insight is groundbreaking, offering a deeper understanding of\nthe molecular structure-performance relationship and laying the groundwork\nfor developing next-generation electron beam resists with superior\nsensitivity, resolution, and contrast for microelectronics manufacturing.