The origin of efficient luminescence in highly porous silicon

doi:10.1016/0022-2313(94)90150-3

Journal of Luminescence

Volumes 60–61, April 1994, Pages 297-301

https://doi.org/10.1016/0022-2313(94)90150-3 Get rights and content

Abstract

The efficient visible luminescence of highly porous silicon is identified using photoluminescence spectroscopy. The observation of momentum-conserving phonon satellites of crystalline silicon shows beyond doubt that crystalline silicon is the luminescent material. We report a weak three-phonon satellite in photoluminescence excitation spectra of porous silicon. This is a manifestation of the weak two-phonon momentum-conserving transitions of crystalline silicon. The exchange splitting of the luminescent exciton is dramatically enhanced by quantum confinement, in agreement with theoretical predictions.

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The origin of efficient luminescence in highly porous silicon

Abstract

Phys. Rev. Lett.

J. Lumin.

J. Phys. C

Appl. Phys. Lett.

Appl. Phys. Lett.

Nature

Phys. Rev. Lett.

Phys. Rev. Lett.

J. Phys.: Condens. Matter