A novel structure of silicon-riched nitride(SRN)/silicon-riched oxide(SRO) is proposed and prepared using RF reactive magnetron co-sputtering. High temperature annealing of SRN/SRO multilayers leads to formation of Si...A novel structure of silicon-riched nitride(SRN)/silicon-riched oxide(SRO) is proposed and prepared using RF reactive magnetron co-sputtering. High temperature annealing of SRN/SRO multilayers leads to formation of Si nanocrystals(NC) from isolating SRN and SRO layers simultaneously, which efficiently improves carrier transport ability compared to conventional SRN/Si_3N_4 counterpart. Micro-Raman scattering analysis reveals that SRN layer has dominating number of denser and smaller Si NCs, while SRO layer has relatively less, sparser and bigger Si NCs, as confirmed by high resolution transmission electron microscopy observation. The substitute SRO layers for Si_3N_4 counterparts significantly increase the amount of Si NCs as well as crystallization ratio in SRN layers; while the average Si NC size can be well controlled by the thickness of SRN layers and the content of N, and hence an obvious stronger absorption in UV region for the novel structure can be observed in absorption spectra. The I-V characteristics show that the current of hybrid SRN/SRO system increases up to 2 orders of magnitude at 1 V and even 5 orders of magnitude at 4 V compared to that of SRN/Si_3N_4 structure. Si NCs in Si Oylayers provide a transport pathway for adjacent Si NCs in Si Nxlayers. The obvious advantage in carrier transportation suggests that SRN/SRO hybrid system could be a promising structure and platform to build Si nanostructured solar cells.展开更多
基金supported by the National Natural Science Foundation of China(No.61036001,51072194and 60906035)
文摘A novel structure of silicon-riched nitride(SRN)/silicon-riched oxide(SRO) is proposed and prepared using RF reactive magnetron co-sputtering. High temperature annealing of SRN/SRO multilayers leads to formation of Si nanocrystals(NC) from isolating SRN and SRO layers simultaneously, which efficiently improves carrier transport ability compared to conventional SRN/Si_3N_4 counterpart. Micro-Raman scattering analysis reveals that SRN layer has dominating number of denser and smaller Si NCs, while SRO layer has relatively less, sparser and bigger Si NCs, as confirmed by high resolution transmission electron microscopy observation. The substitute SRO layers for Si_3N_4 counterparts significantly increase the amount of Si NCs as well as crystallization ratio in SRN layers; while the average Si NC size can be well controlled by the thickness of SRN layers and the content of N, and hence an obvious stronger absorption in UV region for the novel structure can be observed in absorption spectra. The I-V characteristics show that the current of hybrid SRN/SRO system increases up to 2 orders of magnitude at 1 V and even 5 orders of magnitude at 4 V compared to that of SRN/Si_3N_4 structure. Si NCs in Si Oylayers provide a transport pathway for adjacent Si NCs in Si Nxlayers. The obvious advantage in carrier transportation suggests that SRN/SRO hybrid system could be a promising structure and platform to build Si nanostructured solar cells.
