Conformal CVD-Grown MoS2 on Three-Dimensional Woodpile Photonic Crystals for Photonic Bandgap Engineering

To achieve the modification of photonic band structures and realize the dispersion control toward functional photonic devices, composites of photonic crystal templates with high-refractive-index material are fabricated. A two-step process is used: 3D polymeric woodpile templates are fabricated by a direct laser writing method followed by chemical vapor deposition of MoS₂. We observed red-shifts of partial bandgaps at the near-infrared region when the thickness of deposited MoS₂ films increases. A ∼10 nm red-shift of fundamental and high-order bandgap is measured after each 1 nm MoS₂ thin film deposition and confirmed by simulations and optical measurements using an angle-resolved Fourier imaging spectroscopy system.