基于双光束光场调制的动态三维阵列超分辨光刻技术研究

Super-resolution nanolithography is a key technology for producing new photonic materials and devices, and improving their performance. The current two-dimensional nanofabrication techniques including electron beam lithography (EBL) and focused ion beam (FIB) lithography provide high resolution. But the major limitation of these techniques is their incapability of three-dimensional (3D) nanofabrication. Single-beam laser direct writing (LDW) technique has a superior 3D nanofabrication. However, because of the diffraction nature of light, single-beam LDW cannot facilitate the nanofabrication of high nanometer resolution that the EBL has. Thus, how to break through the optical diffraction limit, and achieve super-resolution in the far optical field and 3D nanofabrication, is one of the important academic topics. This project will be carried out super-resolution 3D nanofabrication in the far optical field by using phase modulation of coaxial two-beam and photoinduction-inhibited nonlinear effect of photolithographic materials, leading to break through the optical diffraction limit and improved resolution in the far-field 3D nanofabrication. We will study the phase modulation of the two beam using spatial light modulator (SLM) and Fourier imaging system, to produce 3D array multifocal spots. And, the position, spot shape and polarization orientation of each spot in the multifocal spots can be effectively controlled using accurate phase manipulations assisted by SLM. It provides a new and high-efficiency dynamic super-resolution 3D nanofabrication technique for metamaterial fabrication.

具有超高分辨率的纳米光刻是制备新型光子材料及器件并提高其性能的关键技术。现有的电子束刻蚀、聚焦离子束刻蚀等二维加工技术，具有极高的空间分辨率，但却不具有快速的三维纳米加工能力。单光束激光直写技术具有优异的远场加工能力，但受限于光学衍射极限，很难实现与电子束刻蚀等同等的加工分辨率。因此，如何突破衍射极限，实现远场超分辨的三维纳米光刻技术，成为当前研究的重要课题。本项目拟通过对同轴双光束的相位及偏振调制的远场聚焦光斑的调控技术和双光束的光激发-光抑制效应，并且利用光刻材料的非线性效应，突破光学衍射极限，提高纳米光刻技术的分辨率，同时实现远场超分辨的三维纳米光刻。通过纯相位空间光调制器和傅里叶变换成像系统对双光束相位调制的研究，产生超高分辨率的形状、位置及偏振可控的三维焦点阵列，实现动态三维的双光束纳米并行加工，为人工微结构材料制作等领域提供一种新型的、高效的远场超分辨三维纳米光刻手段。