Enhancing light emission of Si nanocrystals by means of high-pressure hydrogenation

High-density Si nanocrystal thin film composed of Si nanocrystals and SiO2, or SiNCs:SiO2, was prepared by annealing hydrogen silsesquioxane (HSQ) in a hydrogen and nitrogen (H-2:N-2=5%:95%) atmosphere at 1100 degrees C. Conventional normal-pressure (1-bar) hydrogenation failed to enhance the light emission of the Si-NCs:SiO2 sample made from HSQ. High-pressure hydrogenation was then applied to the sample in a 30-bar hydrogen atmosphere for this purpose. The light emission of Si-NCs increased steadily with increasing hydrogenation time. The photoluminescence (PL) intensity, the PL quantum yield, the maximal electroluminescence intensity, and the optical gain were increased by 90%, 114%, 193% and 77%, respectively, after 10-day high-pressure hydrogenation, with the PL quantum yield as high as 59 degrees 70, under the current experimental condition. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement