Realization of high aspect ratio metalenses by facile nanoimprint lithography using water-soluble stamps
Realization of high aspect ratio metalenses by facile nanoimprint lithography using water-soluble stamps
复制标题
使用水溶性印模通过简便的纳米压印光刻实现高纵横比超透镜
作者：
Hojung Choi;Joo;Won;Junhwa Seong;Chanwoong Park;M. Choi;N. Kim;Jisung Ha;Cheng;J. Rho;Heon Lee
纳米压印光刻(NIL)作为一种低成本、高产量的介电金属材料制备方法，近年来引起了人们的广泛关注。然而，需要高纵横比(HAR)的纳米结构来操纵光的全2π位相。采用硬质聚二甲基硅氧烷(h-PDMS)模具的常规NIL不可避免地会在纳米结构上产生剪应力，而剪应力与平行于剥离方向的表面积成反比。因此，HAR结构承受较大的剪应力，导致结构破坏。在此，我们提出了一种新的无剥离工艺的湿法无腐蚀方法来制备无缺陷的HAr金属。水溶性复制品模具是用聚乙烯醇(PVA)制造的，比h-PDMS模具简单，PVA模具的灵活性适合直接打印，因为其高拉伸模数允许高分辨率的HAR金属图案化。印刷金属透镜的衍射限制聚焦表明，它在可见光区域是一种理想的透镜。这种方法有可能用于制造各种需要HAr纳米结构的纳米光电子器件，成本低，产量高，有利于商业化。
Nanoimprint lithography (NIL) has attracted attention recently as a promising fabrication method for dielectric metalenses owing to its low cost and high throughput, however, high aspect ratio (HAR) nanostructures are required to manipulate the full 2π phase of light. Conventional NIL using a hard-polydimethylsiloxane (h-PDMS) mold inevitably incurs shear stress on the nanostructures which is inversely proportional to the surface area parallel to the direction of detachment. Therefore, HAR structures are subjected to larger shear stresses, causing structural failure. Herein, we propose a novel wet etching NIL method with no detachment process to fabricate flawless HAR metalenses. The water-soluble replica mold is fabricated with polyvinyl alcohol (PVA) which is simpler than an h-PDMS mold, and the flexibility of the PVA mold is suitable for direct printing as its high tensile modulus allows high-resolution patterning of HAR metalenses. The diffraction-limited focusing of the printed metalenses demonstrates that it operates as an ideal lens in the visible regime. This method can potentially be used for manufacturing various nanophotonic devices that require HAR nanostructures at low cost and high throughput, facilitating commercialization.
影响因子：
38.3
作者：
Zheng, Guoxing;Muehlenbernd, Holger;Zhang, Shuang
通讯作者：
Zhang, Shuang
影响因子：
17.1
作者：
McPhillips, John;Murphy, Antony;Pollard, Robert J.
通讯作者：
Pollard, Robert J.