Micro Grating Deposition on Non‐Planar Surfaces by Polymer‐Assisted Transfer Printing

By spin‐coating a few hundred of nanometer thick poly(methyl methacrylate) (PMMA) film on a micron or a sub‐micron scale structure, the structure can be transferred on an arbitrary substrate. More precisely, by using a thin PMMA support layer and releasing the structure from the transient substrate into water, the PMMA with the structure can be collected on a desired substrate. Here, this technique is demonstrated to be suitable for transferring metallic binary grating and few‐layer Bragg gratings from flat substrates onto 3D‐printed convex lenses. Moreover, the thin PMMA film is sufficiently strong to support centimeter size free‐standing areas. This enables fabrication of 1.5 μm thick, free‐standing structure of a Bragg‐grating with PMMA. Thus, the presented technique provides a powerful tool for transfer printing of micron scale structures. Micro‐grating structures are conventionally fabricated on flat surfaces. However, by using a thin poly(methyl methacrylate) (PMMA) film those micro‐scale structures can be transferred on nonplanar surfaces or can be made free‐standing. The presented technique that mimics graphene wet‐transfer technique is suitable for transferring metallic and dielectric grating structures on arbitrary substrates.