Wafer Scale Formation of Monocrystalline Silicon-Based Mie Resonators via Silicon-on-Insulator Dewetting

Abstract

Subwavelength-sized dielectric Mie resonators have recently emerged as a promising photonic platform, as they combine the advantages of dielectric microstructures and metallic nanoparticles supporting surface plasmon polaritons. Here, we report the capabilities of a dewetting-based process, independent of the sample size, to fabricate Si-based resonators over large scales starting from commercial silicon-on-insulator (SOI) substrates. Spontaneous dewetting is shown to allow the production of monocrystalline Mie-resonators that feature two resonant modes in the visible spectrum, as observed in confocal scattering spectroscopy. Homogeneous scattering responses and improved spatial ordering of the Si-based resonators are observed when dewetting is assisted by electron beam lithography. Finally, exploiting different thermal agglomeration regimes, we highlight the versatility of this technique, which, when assisted by focused ion beam nanopatterning, produces monocrystalline nanocrystals with ad hoc size, position, and organization in complex multimers.

Self-assembled antireflection coatings for light trapping based on SiGe random metasurfaces

“…All these properties can be modified by adding Ge before, during or after dewetting [42][43][44][45]60,61,63 potentially providing full control over their physical properties. However, in SiGe-based samples, Si-rich and Ge-rich particles are spatially separate, leading to large inhomogeneities of the morphological properties over micrometric distances 44,60,61 that make this method unsuitable for performing devices.…”

“…One viable and promising route is solid-state dewetting of ultra-thin films of metals 18,[34][35][36][37][38][39][40][41] and semiconductors, [42][43][44][45][46] a natural phenomenon exploited for the self-assembly of high-quality photonic structures. The instability giving rise to the dewetting phenomenon in thin films is mediated by the surface diffusion of atoms and occurs upon annealing at high temperature (even well below the melting point of the material) [47][48][49][50][51][52][53][54][55][56][57][58] .…”

Laser fabrication of crystalline silicon nanoresonators from an amorphous film for low-loss all-dielectric nanophotonics

“…Therefore, various methods of the resonant silicon nanoparticles fabrication have been developed during last years, including colloidal chemistry 23 , thin film dewetting 24 and laser ablation 6,25 , where initially crystalline samples or additional annealing were used to achieve crystalline state of the nanoparticles.…”

Nanoporous Ge thin film production combining Ge sputtering and dopant implantation

“…In addition, the structure of the dewetted layers can be controlled using several techniques such as pulsed laser annealing [35,36] or a substrate patterned by focused ion beam. The study of Ge dewetting on SiO 2 [37] has already been reported in the literature, however, only in the case of very thin amorphous Ge layers (5−15 nm thick) [38][39][40].…”