Top down Fabrication of Silicon Photonic Structures by Metal Assisted Chemical Etching

Silicon, the ubiquitous material for computer chips, has recently been shown to be instrumental for hosting sources of single-photons emitting in the strategic optical telecommunication O-band (1260-1360 nm)[1], the so-called G center. To increase the brightness and the photon extraction efficiency of single G center, the coupling of these centers into photonic structures is strong.
This work presents a top-down approach avoiding the use of ion beam-based etching methods for fabricating high-quality defect-free photonic structures such as silicon nanopillars, which can host single photon emitters. This method builds upon a wet-chemical process known as MACEtch. We report the successful fabrication of two-dimensional arrays of vertically directed wave guiding silicon nanopillars. The confocal microscopy after carbon ion implantation shows presence of ensembles of G centers.