Oligomers of MORE: Molecular Organometallic Resists for EUV

The EUV photoproducts of antimony carboxylate photoresists [R3Sb(O2CR')(2)] are used to evaluate a possible free radical exposure mechanism by studying the change in molecular weight distribution with dose. We demonstrate the redistribution of carboxylate ligands across the metal centers in solution and use this property to create a statistical mono-olefin resist system with blended solutions of olefinic and non-olefinic antimony compounds that limit crosslinking and improve solubility of the photoproducts. Through gel permeation chromatography (GPC) analysis, we demonstrate the formation of high molecular weight oligomers with exposure dose and provide further support for the free-radical polymerization mechanism.