Enhancement of green electroluminescence from nanocrystalline silicon by wet and dry processes.
Correlation between defects and luminescence property from electroluminescent (EL) device composed of nanocrystalline silicon (nc-Si) prepared by wet and dry processes such as hydrofluoric (HF) acid solution treatment and annealing have investigated using electron spin resonance and EL measurements. The EL device using HF-treated nc-Si emitted strong red light, because of existence of only P'ce-centers (radiative recombination centers) on the surface vicinity. On the other hand, the EL device using annealed nc-Si above 400 degrees C exhibited green luminescence by the reduction of particle size due to surface oxidation. When the annealing temperature was risen from 400 degrees C up to 600 degrees C, the green luminescence strengthened with increasing the P'ce-centers. These results indicate that the formation of many radiative recombination centers onto the nc-Si surface vicinity lead to the enhancement of green luminescence from the nc-Si based EL device.
Department of Electronic and Computer Engineering, Tokyo Denki University, Ishizaka, Hatoyama, Hikigun, Saitama 350-0394, Japan.
Keisuke
K
Sato
Kenji
K
Hirakuri
D003116:Color; D004563:Electrochemistry; D004578:Electron Spin Resonance Spectroscopy; D049449:Luminescence; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water
D014867:Water; D012825:Silicon