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Optical Properties of Free-Standing Porous Si Films

  • Y. Kanemitsu (a1), H. Uto (a1), Y. Masumoto (a1), T. Matsumoto (a2), T. Futagi (a2) and H. Mimura (a2)...


We have studied optical properties of free-standing porous Si thin films fabricated by electrochemical anodization. The average diameter of Si crystallite spheres is evaluated by Raman spectroscopy and transmission electron microscopy. The blueshift of optical absorption spectrum is observed with a decrease in the average diameter of Si crystallites. However, there is no clear size dependence of the peak energy of broad photoluminescence spectrum. Spectroscopic analysis strongly suggests that the photogeneration of carriers occurs in the c-Si core whose band gap is modified by the quantum confinement effect, whereas the radiative recombination of carriers occurs in the near-surface region of small crystallites.



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Optical Properties of Free-Standing Porous Si Films

  • Y. Kanemitsu (a1), H. Uto (a1), Y. Masumoto (a1), T. Matsumoto (a2), T. Futagi (a2) and H. Mimura (a2)...


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