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In this work, the porous silicon (PS) was used to fabricate
porous siliconlight-emitting diodes (PS-LED). The PL
(photoluminescence) spcetrum of the usedporous silicon having PS
without oxidation had three peaks at about 660, 465, and 404 nm,
respectively. The PL spectrum of PS was blue-shifted after the
PSsample was oxidized at a high temperature around 950^oC. The
first p(PS)-n-i-p-n(a-Si:H) PS-LED with unoxidized had an EL
(electroluminescence) threshold voltage of about 8.2 V, and its
brightness was about 18cd/m^2 at an injectioncurrent density of
600 mA/cm^2. The second p(PS)-n-i-p-n(a-Si:H) PS-LED
havingoxidized PS, had an EL threshold voltage of about 47.6 V,
and its brightness was about 3 cd/m^2. The peaks of EL spectra
for PS-LED's having various oxid-ized PS's were also blue-
shifted to about 450 and 530 nm, silimar to the PL spectrum of
unoxidized PS. A green-blue or blue light emission from a PS-
LEDhaving an oxidized PS was observable in the dark with naked
eyes.
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