{'fraction_non_alphanumeric': 0.03556485355648536, 'fraction_numerical': 0.02301255230125523, 'mean_word_length': 4.696428571428571, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A combined approach to greatly enhancing the photoluminescence of Si nanocrystals embedded in SiO2

An approach combining back- and front-side doping of Ce3+ in Si nanocrystals embedded in SiO2 (nc-Si:SiO2) with hydrogen passivation has been developed, which largely enhances the photoluminescence (PL) of Si nanocrystals. The sample of nc-Si:SiO2 was prepared via a phase separation process of SiO thin film at 1100 °C. For the back-side doping, a SiO2 buffer layer was placed between the CeF3 layer and SiO one, thus Ce3+ doping could be accomplished without disrupting the phase separation of SiO. The front-side doping was then followed by evaporating CeF3 onto the front surface of the formed nc-Si:SiO2, followed by diffusion annealing at 500 °C. The double-side doping enhanced the PL intensity of Si nanocrystals by a factor of 7.3. After hydrogenation of the double-side doped sample, a 14.6-fold increase in the PL intensity was finally achieved.