Department of Electrical Engineering and Applied Physics, Yale University, New Haven, CT 06520, USA.
Nanotechnology. 2012 Feb 3;23(4):045301. doi: 10.1088/0957-4484/23/4/045301. Epub 2012 Jan 4.
We report a single-step lithographic approach for precisely mapping near field light diffraction in photoresist and fabricating complex subwavelength structures. This method relies on the diffraction of UV light from opaque patterns on a photomask, and utilizes the central diffraction maximum (known as the 'Poisson spot' for an opaque disk) and its higher orders. By correlating pattern geometries with the resulting diffraction, we demonstrate that the near field light intensity can be quantified to high precision and is in good agreement with theory. The method is further extended to capture higher order diffraction, which is utilized to fabricate unconventional subwavelength nanostructures with three-dimensional topographies. The simplicity of this process and its capability for light mapping suggest it to be an important tool for near field optical lithography.
我们报告了一种单步光刻方法，用于精确映射光致抗蚀剂中的近场光衍射，并制造复杂的亚波长结构。该方法依赖于光掩模上不透明图案的紫外光衍射，并利用中心衍射最大值（对于不透明盘，称为“泊松光斑”）及其更高阶。通过将图案几何形状与产生的衍射相关联，我们证明可以高精度地量化近场光强度，并且与理论吻合良好。该方法进一步扩展到捕获更高阶衍射，利用该衍射来制造具有三维形貌的非常规亚波长纳米结构。该过程的简单性及其光映射能力表明它是近场光学光刻的重要工具。
