Single-photon emitters in PECVD-grown silicon nitride films: from material growth to photophysical properties.

Silicon nitride (SiN) is a key material for quantum photonics due to its wide transparency window, high refractive index, low optical losses, and semiconductor foundry compatibility. We study the formation of single-photon emitters in SiN films grown by plasma-enhanced chemical vapor deposition (PECVD), exploring their photophysical properties and dependence on growth conditions. Emitters were observed across the entire range of nitrogen-to-silicon precursor ratios, from silicon-rich to nitrogen-rich conditions, enabled by the low background fluorescence. We demonstrate single-photon emitters in SiN films with a higher refractive index (1.8-1.9) compared to our previous reports (∼1.7). Notably, nitrogen-rich, thinner films yield particularly bright emitters with shorter emission lifetimes, likely due to more efficient annealing. Silicon-rich SiN films exhibit red-shifted emission, suggesting that composition may provide a mechanism for wavelength tuning. These findings establish the feasibility of emitters formation in foundry standard PECVD tools, advancing the scalability and lab-to-fab transition of SiN-based quantum photonic technologies.