High Transmittance and High Diffraction Efficiency with SiN Metasurface Holograms

The high 92% transmittance and 73% diffraction efficiency were achieved in polarization-independent full-color metasurface holograms made of silicon nitride (SiN) high-aspect-ratio nanopillars. The absolute efficiency of 67% calculated from these results is a significant improvement over the results reported at IEEE-MEMS-2023 [1]. This achievement was obtained by optimizing the RIE conditions for SiN, a meta-atom material with high transmittance in the visible light range. A full-color dielectric metasurface holographic image was achieved by spatially multiplexing frames with blue, green, and red color channels at the wavelengths of 445 nm, 532 nm, and 633 nm.