Fabricating 3D Metastructures by Simultaneous Modulation of Flexible Resist Stencils and Basal Molds

• Published in: Advanced materials (Weinheim) Vol. 32; no. 36; pp. e2002570 - n/a
• Main Authors: Cai, Hongbing, Meng, Qiushi, Chen, Qiang, Ding, Huaiyi, Dai, Yanmeng, Li, Sijia, Chen, Disheng, Tan, Qinghai, Pan, Nan, Zeng, Changgan, Qi, Zeming, Liu, Gang, Tian, Yangchao, Gao, Weibo, Wang, Xiaoping
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.09.2020
• Subjects: 3D fabrication; Contact angle; Controllability; flexible resist stencils; Materials science; metallic spirals; Metamaterials; metastructures; Molds; Morphology; Optical properties; Robust control; split‐ring resonators
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202002570

Metamaterials have gained much attention thanks to their extraordinary and intriguing optical properties beyond natural materials. However, universal high‐resolution fabrications of 3D micro/nanometastructures with high‐resolution remain a challenge. Here, a novel approach to fabricate sophisticated 3D micro/nanostructures with excellent robustness and precise controllability is demonstrated by simultaneously modulating of flexible resist stencils and basal molds. This method allows arbitrary manipulations of morphology, size, and orientation, as well as contact angles of the objects. Combined with a new alignment strategy of high‐resolution, previously inaccessible architectures are fabricated with ultrahigh precision, leading to an excellent spectra response from the fabricated metastructures. This method provides a new possibility to realize true 3D metamaterial fabrications featuring high‐resolution and direct‐compatibility with broad planar lithography platforms. Orthotropic control of resist stencils and basal molds is developed to realize high‐resolution true triaxial fabrication of 3D metastructures. New strategies to modulate the basal mold with high precision are realized by a controlled annealing process. A new alignment technique is also introduced to stacking the 3D metastructures with high addressability.