A model of quantum confined state modified by surface potential in porous silicon

Xue, F. S.; Bao, Xiaoguang; Yan, Feng

doi:10.1063/1.364146

Cited by 11 publications

(8 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2,3 The origin of light emission has been extensively studied. [4][5][6] The similarity between PL and EL spectra indicates that a common recombination mechanism is involved in both cases but the quantum efficiency of the EL is smaller than that of the PL by at least one order of magnitude. In order to improve the efficiency, it is important to study the influence of recombination centers, surface states, and electrical contacts on the EL and PL.…”

Section: Introductionmentioning

confidence: 97%

Transport mechanisms in porous silicon

Ray¹,

Mabrook²,

Nabok³

et al. 1998

Journal of Applied Physics

View full text Add to dashboard Cite

The current transport mechanism through porous silicon ͑PS͒ films fabricated from 8 to 12 ⍀ cm p-type silicon (p-Si) substrates has been investigated using current-voltage I(V) measurements on metal/PS/p-Si/metal devices in the temperature range of 77-300 K. The characteristics for all devices show a rectifying behavior with ideality factor very close to unity. A value of 0.7 eV is obtained for the barrier height at the interface between PS and bulk p-Si at room temperature and the barrier height is found to increase with rising temperature. A band model is proposed in order to explain the observed characteristics.

show abstract

Section: Introductionmentioning

confidence: 97%

Transport mechanisms in porous silicon

Ray¹,

Mabrook²,

Nabok³

et al. 1998

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…With increasing the storage time, the Fe 2 O 3 layer will thicken as a result of the increase of the Fe-O bond density. 15 If considering the presence of a transition region between the ␤-FeSi 2 and Fe 2 O 3 layers and its thinning caused by its stor-age in air, we found that the band-mixing model, 14 which can give the energy levels of electrons and holes confined in the Si/ FeSi 2 nanocomposite consisting of nanocrystalline Si core, interfacial FeSi 2 layer, and outer Fe 2 O 3 crust, can explain very well the observed PL intensity increase with the sample storage time and the pinning behavior of the PL peak position. This implies that the PL behavior from the FePS samples is related to both the quantum confinement of Si nanocrystal and its surface passivation ͑the formation of Fe-Si and Fe-O bonds͒.…”

Section: Resultsmentioning

confidence: 89%

“…For PS, many experiments have demonstrated that its luminescence property is not only determined by the quantum confinement effect of Si nanocrystals but also controlled by the surface chemical bonds. [8][9][10][11][12][13][14] Both the surface layer and nc-Si core constitute a nanoparticle composite. Naturally, its luminescence is a result of the interaction of the two nanoparticles.…”

Section: Introductionmentioning

confidence: 99%

Photoluminescence from C60-coupled porous structures formed on Fe+-implanted silicon

Zhang

Qiu

et al. 2006

The Journal of Chemical Physics

View full text Add to dashboard Cite

111-oriented p-type Si wafer with a resistivity of 1-5 Omega cm was implanted with Fe+ and then annealed at 1100 degrees C in N2 for 60 min, followed by anodization in a solution of HF to form porous structure with beta-FeSi2 nanocrystallites. Photoluminescence (PL) spectral measurements show that a strong PL peak appears in the range of 610-670 nm. The position of the PL peak remains unchanged, but its intensity increases with the storage time in air until about three months and then saturates. C60 molecules were chemically coupled on the porous structure through a kind of silane coupling agent to form a nanocomposite. It is revealed that the stable PL peak monotonically shifts to a pinning wavelength at 570 nm. Experimental results from PL, PL excitation, Raman scattering, and x-ray diffraction measurements clearly show that the pinned PL originates from optical transition in C60-related defect states, whereas the photoexcited carriers occur in the beta-FeSi2 nanocrystallites formed during anodization. This work opens a new way to tailor nanometer environment for seeking optimal luminescent properties.

show abstract

“…To get a comprehensive understanding of underlying physical phenomena, the porous Si has been intensively studied using various theoretical methods, namely by model calculations [18,19], effective mass approximation [20], tight binding [21,22], density functional theory [23][24][25][26].…”

Section: Introductionmentioning

confidence: 99%

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

et al. 2020

View full text Add to dashboard Cite

The paper reports the results on first-principles investigation of energy band spectrum and optical properties of bulk and nanoporous silicon. We present the evolution of energy band-gap, refractive indices and extinction coefficients going from the bulk Si of cubic symmetry to porous Si with periodically ordered square-shaped pores of 7.34, 11.26 and 15.40 Å width. We consider two natural processes observed in practice, the hydroxylation of Si pores (introduction of OH groups into pores) and the penetration of water molecules into Si pores, as well as their impact on the electronic spectrum and optical properties of Si superstructures. The penetration of OH groups into the pores of the smallest 7.34 Å width causes a disintegration of hydroxyl groups and forms non-bonded protons which might be a reason for proton conductivity of porous Si. The porosity of silicon increases the extinction coefficient, k, in the visible range of the spectrum. The water structuring in pores of various diameters is analysed in detail. By using the bond valence sum approach we demonstrate that the types and geometry of most of hydrogen bonds created within the pores manifest a structural evolution from distorted hydrogen bonds inherent to small pores (∼7 Å) to typical hydrogen bonds observed by us in larger pores (∼15 Å) which are consistent with those observed in a wide database of inorganic crystals.

show abstract

A model of quantum confined state modified by surface potential in porous silicon

Cited by 11 publications

References 21 publications

Transport mechanisms in porous silicon

Transport mechanisms in porous silicon

Photoluminescence from C60-coupled porous structures formed on Fe+-implanted silicon

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

Contact Info

Product

Resources

About