Three-dimensional (3D) nanofabrication techniques are of paramount importance in nanoscience and nanotechnology because they are prerequisites to realizing complex, compact, and functional 3D nanodevices. Although several 3D nanofabrication methods have been proposed and developed in recent years, it is still a formidable challenge to achieve a balance among resolution, accuracy, simplicity, and adaptability. Here, we propose a 3D nanofabrication method based on electron-beam lithography using ice resists (iEBL) and fabricate 3D nanostructures by stacking layered structures and those with dose-modulated exposure, respectively. The entire process of 3D nanofabrication is realized in one vacuum system by skipping the spin-coating and developing steps required for commonly used resists. This needs far fewer processing steps and is contamination-free compared with conventional methods. With in situ alignment and correction in the iEBL process, a pattern resolution of 20 nm and an alignment error below 100 nm can be steadily achieved. This 3D nanofabrication technique using ice thus shows great potential in the fabrication of complicated 3D nanodevices.

中文翻译：

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使用水冰的三维原位电子束光刻

三维（3D）纳米制造技术在纳米科学和纳米技术中至关重要，因为它们是实现复杂，紧凑且功能强大的3D纳米设备的先决条件。尽管近年来已经提出并开发了几种3D纳米制造方法，但要在分辨率，准确性，简单性和适应性之间取得平衡仍然是一个艰巨的挑战。在这里，我们提出了一种基于电子束光刻技术的3D纳米制造方法，该技术使用的是抗冰剂（iEBL），并分别通过堆叠层状结构和具有剂量调制曝光的结构堆叠3D纳米结构。通过跳过常用抗蚀剂所需的旋涂和显影步骤，可在一个真空系统中实现3D纳米制造的整个过程。与传统方法相比，这需要少得多的处理步骤并且无污染。通过iEBL工艺中的原位对准和校正，可以稳定地实现20 nm的图案分辨率和低于100 nm的对准误差。因此，这种使用冰的3D纳米制造技术在制造复杂的3D纳米设备中显示出巨大的潜力。