Novel polymeric anionic photoacid generators (PAGs) and corresponding polymers for 193 nm lithography
作者:Mingxing Wang、Nathan D. Jarnagin、Cheng-Tsung Lee、Clifford L. Henderson、Wang Yueh、Jeanette M. Roberts、Kenneth E. Gonsalves
DOI:10.1039/b607918k
日期:——
A series of new anionic PAGs, as well as PAG-bound polymers designed for use in 193 nm photoresist materials, have been synthesized and characterized. These novel materials provide optical transparency at 193 nm and also good etch resistance. PAG incorporated resists and PAG blended resists were exposed at a wavelength of 193 nm using an ASML 5500/950B optical lithography system with 0.63 NA. Exposed wafers were evaluated using SEM. The fluorine substituted PAG bound polymer and PAG blend resist provided a 110 nm (220 nm pitch) line/space at 11.5, 13.0 mJ cm−2, and 80 nm isolated features at 3 and 1 mJ cm−2, respectively. The LER (3σ) results showed that the fluorinated PAG bound polymer has LER values of 6.7 and 6.8 nm for isolated 80 nm and dense 110 nm lines, respectively, while the fluorinated PAG blend resist has LER values of 8.6 and 8.9 nm. The improvement may be due to the direct bonding of PAG into the polymer main-chain, which provides a more uniform distribution, thereby controlling acid diffusion and allowing a higher loading of PAG than the blend sample. The fluorine-free PAG bound or blend resists showed lower photospeed compared to photoresists based on fluorine-substituted PAGs.
我们合成了一系列新型阴离子 PAG 以及 PAG 结合聚合物,并对其进行了表征,这些聚合物设计用于 193 纳米光刻胶材料。这些新型材料在 193 纳米波长下具有光学透明度和良好的抗蚀刻性。使用波长为 193 纳米的 ASML 5500/950B 光学光刻系统(0.63 NA),对含有 PAG 的光刻胶和 PAG 混合光刻胶进行了曝光。使用 SEM 对曝光的晶片进行评估。氟取代的 PAG 结合聚合物和 PAG 混合抗蚀剂分别在 11.5 和 13.0 mJ cm-2 下提供了 110 nm(220 nm 间距)的线/间距,在 3 和 1 mJ cm-2 下提供了 80 nm 的孤立特征。LER (3σ) 结果显示,含氟 PAG 结合聚合物的 80 nm 隔离线和 110 nm 密集线的 LER 值分别为 6.7 nm 和 6.8 nm,而含氟 PAG 混合抗蚀剂的 LER 值分别为 8.6 nm 和 8.9 nm。这种改进可能是由于 PAG 直接粘合到聚合物主链中,使其分布更加均匀,从而控制了酸的扩散,使 PAG 的负载量高于共混样品。与基于氟取代 PAG 的光刻胶相比,无氟 PAG 结合型或混合型光刻胶的光速较低。