Hydrogen silsesquioxane (HSQ) is a negative tone electron-beam resist. The Hydrogen silsesquioxane monomer is a cubical-shaped molecule having one Si atom at each corner, with corners being linked via oxygen atoms. Additionally, a hydrogen group is attached to each Si. The formula of the HSQ monomer is H8Si8O12. Thin HSQ layers have been used to show very high resolution (~10 nm) feature sizes.[1] It can be cross-linked by exposure to e-beam or EUV radiation with wavelengths shorter than 157 nm.
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