Time-Resolved Photoluminescence Study of Silicon Nanoporous Pillar Array

【摘要】 A silicon nanoporous pillar array(Si-NPA) is thought to be a promising functional substrate for constructing a variety of Si-based optoelectronic nanodevices,due to its unique hierarchical structure and enhanced physical properties.This makes the in-depth understanding of the photoluminescence(PL) of Si-NPA crucial for both scientific research and practical applications.In this work,the PL properties of Si-NPA are studied by measuring both the steady-state and time-resolved PL spectrum.Based on the experimental data,the three PL bands of Si-NPA,i.e.,the ultraviolet band,the purple-blue plateau and the red band are assigned to the oxygen-excess defects in Si oxide or silanol groups at the surface of Si nanocrystallites(nc-Si),oxygen deficiency defects in Si oxide,and band-to-band transition of nc-Si under the frame of quantum confinement combining with the surface states like Si=O and Si-O-Si bonds at the surface of nc-Si,respectively.These results may provide some novel insight into the PL process of Si-NPA and may be helpful for clarifying the PL mechanism.更多还原

【Abstract】 A silicon nanoporous pillar array(Si-NPA) is thought to be a promising functional substrate for constructing a variety of Si-based optoelectronic nanodevices,due to its unique hierarchical structure and enhanced physical properties.This makes the in-depth understanding of the photoluminescence(PL) of Si-NPA crucial for both scientific research and practical applications.In this work,the PL properties of Si-NPA are studied by measuring both the steady-state and time-resolved PL spectrum.Based on the experimental data,the three PL bands of Si-NPA,i.e.,the ultraviolet band,the purple-blue plateau and the red band are assigned to the oxygen-excess defects in Si oxide or silanol groups at the surface of Si nanocrystallites(nc-Si),oxygen deficiency defects in Si oxide,and band-to-band transition of nc-Si under the frame of quantum confinement combining with the surface states like Si=O and Si-O-Si bonds at the surface of nc-Si,respectively.These results may provide some novel insight into the PL process of Si-NPA and may be helpful for clarifying the PL mechanism.更多还原