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

摘要： 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.