Assembly of large hBN nanocrystal arrays for quantum light emission

Abstract We fabricate rectangular arrays of hexagonal boron nitride (hBN) nanoplatelet clusters extending over hundreds of microns. Positioning is achieved by capillary assembly of suspended hBN particles into submicron polymer holes, patterned by electron-beam lithography. After removal of the patterned polymer from the SiO₂/Si surface, average positioning yields of 74% at the desired locations are routinely achieved. At 10% of the locations, single-photon emitters (SPEs) are found. Thermal post-annealing of the prepared samples at 850 °C increases the number of SPEs by 50%. Our work paves the way for the production of wafer-scale SPE arrays based on commercially available hBN nanocrystals for a systematic statistical analysis of individually addressable SPEs, as well as for deterministic coupling of many emitters to a large number of photonic structures on photonic chips.