Evolution of the porous silicon sample properties in the atmospheric ambient

Dacenko, O.I.; Макара, В. А.; Naumenko, S. N.; Ostapchuk, T. V.; Руденко, О. В.; Shevchenko, V. B.; Vakulenko, O. V.; Boltovets, Mykola S.

doi:10.1016/s0022-2313(99)00012-5

Cited by 8 publications

(9 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These compounds are the PL sensitizers in PS [12,13]. According to the supposition of [10], the interaction of PS with oxygen takes place preferentially near the surface of porous layer when storing the sample in the air. After a prolonged contact with the atmosphere, an emitting layer is formed in the near-surface region.…”

Section: Resultsmentioning

confidence: 99%

“…In principle, this correlates with the most of data for the PL intensity behaviour when ageing a PS sample in the air (see, e.g., [3,4,6,9,11]). The causes for the rise of PS PL intensity in the air are associated with the atmospheric oxidation of the nanostructure [10]: increase of the sensitizer mass (which is the Si oxide for UV region of excitation [12]), effective saturation of the silicon dangling bonds (nonradiative recombination cen- ters [2]) by oxygen, and the nanostructure modification due to the oxidation. For the reference sample which was stored in the dark, a monotonous increase of PL intensity is documented as well, but it was significantly slower than that for the laser-illuminated sample.…”

Section: Resultsmentioning

confidence: 99%

“…After anodizing, the samples were kept in the air for 3 months. Their luminescence intensities essentially increased during that period of time, which occurred, probably, due to effects of porous layer oxidation [9,10]. Immediately before the experiment, the samples were chemically etched in HF for 3 seconds.…”

Section: Methodsmentioning

confidence: 99%

“…Such a treatment returned the nanostructure surface to the initial state, that is, removed the surface oxide and saturated the external silicon bonds by hydrogen. Furthermore, the porous layer surface cracks as a result of the HF treatment, which promotes the penetration of oxygen into the depth of porous layer and accelerates the PS ageing process [10,11].…”

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Evidence for photochemical transformations in porous silicon

Shevchenko¹

1999

Semicond. Phys. Quantum Electron. Optoelectron.

View full text Add to dashboard Cite

The dynamics of the variation of photoluminescence intensity (PLI) of porous silicon (PS) samples subjected to laser irradiation (337 nm, 3.7 mW) during their ageing in air has been studied. The PLI turned out to increase rapidly under UV irradiation and to flatten out in several hours. The subsequent irradiation leads to intensity degradation, which may be explained by the luminescence fatigue effect. At the same time, the PLI of the unilluminated sample almost does not change during the experiment. It turned out that the anomaly as a small surge down is observed on the PLI evolution curve at the stage of the initial monotonous increase of PLI after a short-time (1 to 2 minutes) interruption of the laser illumination of the sample, whereas this anomaly is a surge up at the stage of the monotonous fall of the PLI curve. In the case of a long-time (tens of hours) discontinuation of illumination, the anomaly was similar for all the portions of the PLI curve. The described results are explained by effect of two competing factors which are the luminescence fatigue and light-induced formation of unstable (molecular) chemical bonds that can transform to the stable atomic ones.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Evidence for photochemical transformations in porous silicon

Shevchenko¹

1999

Semicond. Phys. Quantum Electron. Optoelectron.

View full text Add to dashboard Cite

show abstract

“…Освещение поверхности видимым или УФ све-том ускоряет ее окисление, что приводит к па-данию интенсивности ФЛ [22]. При выдержи-вании ПК на воздухе и дневном освещении интенсивность ФЛ возрастает [23], причем с большей скоростью, чем для образцов, кото-рые находились в темноте. Имеются сведения [24] о химическом окислении ПК с помощью Н 2 О 2 или HNO 3 .…”

Section: 1окислениеunclassified