We used a negative-tone e-beam resist (N-ER) to perform direct laser writing lithography based on a single-photon absorption process with a 405-nm laser source. The linewidth of the N-ER reached 150 nm, which is over three times thinner than that of a conventional photoresist. To optimize the process, the linewidth, lithographic contrast, and aspect ratio of the N-ER were investigated with respect to the dose and baking temperature. We were able to achieve a lithographic contrast of 4.8 and a maximum aspect ratio of 1.43, thereby confirming the superior resolution of the N-ER.

中文翻译：

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使用负性电子束抗蚀剂的直接激光写入光刻

我们使用负型电子束抗蚀剂 (N-ER​​) 来执行基于单光子吸收工艺和 405 nm 激光源的直接激光写入光刻。N-ER 的线宽达到 150 nm，比传统光刻胶的线宽薄三倍以上。为了优化工艺，研究了 N-ER 的线宽、光刻对比度和纵横比与剂量和烘烤温度的关系。我们能够实现 4.8 的光刻对比度和 1.43 的最大纵横比，从而证实了 N-ER 的卓越分辨率。