Nanoimprint lithography by combining STM, plasma etching and micromolding

提出并验证了一种几十纳米、高深宽比的高通量光刻方法。我们已经证明，使用扫描探针显微镜(SPM)的尖端可以在聚合物抗蚀剂上形成纳米级的结构。在扫描隧道显微镜(STM)的尖端压痕形成直径20 nm、深度10 nm的孔的情况下。利用原子力显微镜(AFM)的压痕和线扫描形成一条宽70 nm、深50 nm的沟槽。此后，使用氧反应离子刻蚀(RIE)来去除凹陷区域中剩余的抗蚀剂。在RIE之后，体貌比不止一个。此外，使用非电解镀镍将蚀刻结构复制到金属(微成型)中。在抗蚀剂中加入脱模剂，可以很好地降低抗蚀剂与模具的粘附性。金属模具的直径和宽度大约是蚀刻结构的1.5倍。看来抗蚀剂被电镀溶液侵蚀了。

A high-throughput lithographic method for CD pits with several tens nanometers and a high aspect ratio is proposed and demonstrated. We have demonstrated that nanometer-scale structuring can be formed on a polymer resist using the tip of a scanning probe microscope (SPM). In case a hole with 20 nm in diameter and 10 nm deep is formed by the indentation of the tip of a scanning tunneling microscope (STM). In case a ditch with 70 nm in width and 50 nm deep is formed by the indentation and the line scan of the tip of an atomic force microscope (AFM). Thereafter, oxygen reactive ion etching (RIE) is used to remove the remaining resist in the indented areas. After the RIE, the aspect ration is more than one. Moreover, the etching structure is copied into metal (micromolding) using non-electrolytic nickel plating. Mold release agents are added into the resists and worked well to reduce the resist adhesion to the mold. The diameter and the width of the metal molds are about one and a half times those of the etching structures. It seems that the resist is eroded by the plating solution.