Reversible Degradation of Photoluminescence in Si/SiGe Three Dimensional Nanostructures

ABSTRACTWe report the degradation of low temperature photoluminescence (PL) from Si/SiGe three-dimensional cluster morphology nanostructures under continuous photoexcitation. The PL intensity initially decreases slowly for about 15 minutes, and then decreases rapidly, until only ∼ 10% of the original PL intensity remains. A complete recovery of the PL requires restoring the sample temperature to ∼ 300K. We propose that a slow accumulation of charge in SiGe clusters enhances the rate of Auger recombination and results in the observed PL degradation.

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Silicon layers grown over SiO2 by liquid phase epitaxy: Electron Microscopical study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017596x ◽

1990 ◽

Vol 48 (4) ◽

pp. 566-567

Author(s):

F. Banhart ◽

F.O. Phillipp ◽

R. Bergmann ◽

E. Czech ◽

M. Konuma ◽

...

Keyword(s):

Electron Microscopy ◽

Liquid Phase ◽

Plasma Etching ◽

Liquid Phase Epitaxy ◽

Three Dimensional ◽

Microscopical Study ◽

Sample Temperature ◽

Structural Defects ◽

Si Substrates ◽

Etched Surface

Defect-free silicon layers grown on insulators (SOI) are an essential component for future three-dimensional integration of semiconductor devices. Liquid phase epitaxy (LPE) has proved to be a powerful technique to grow high quality SOI structures for devices and for basic physical research. Electron microscopy is indispensable for the development of the growth technique and reveals many interesting structural properties of these materials. Transmission and scanning electron microscopy can be applied to study growth mechanisms, structural defects, and the morphology of Si and SOI layers grown from metallic solutions of various compositions.The treatment of the Si substrates prior to the epitaxial growth described here is wet chemical etching and plasma etching with NF3 ions. At a sample temperature of 20°C the ion etched surface appeared rough (Fig. 1). Plasma etching at a sample temperature of −125°C, however, yields smooth and clean Si surfaces, and, in addition, high anisotropy (small side etching) and selectivity (low etch rate of SiO2) as shown in Fig. 2.

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LOW TEMPERATURE PHOTOLUMINESCENCE AND ABSORPTION OF GaxIn1-xAs/ InP

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1982543 ◽

1982 ◽

Vol 43 (C5) ◽

pp. C5-383-C5-392 ◽

Cited By ~ 2

Author(s):

K. H. Goetz ◽

A. V. Solomonov ◽

D. Bimberg ◽

H. Jürgensen ◽

M. Razeghi ◽

...

Keyword(s):

Low Temperature ◽

Low Temperature Photoluminescence

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Rapid Growth of TiO2 Nanoflowers via Low-Temperature Solution Process: Photovoltaic and Sensing Applications

Materials ◽

10.3390/ma12040566 ◽

2019 ◽

Vol 12 (4) ◽

pp. 566 ◽

Cited By ~ 7

Author(s):

M. Akhtar ◽

Ahmad Umar ◽

Swati Sood ◽

InSung Jung ◽

H. Hegazy ◽

...

Keyword(s):

Low Temperature ◽

Anatase Phase ◽

Three Dimensional ◽

Solution Process ◽

Dye Sensitized Solar Cell ◽

Sensor Applications ◽

Dye Sensitized ◽

Sensing Applications ◽

Density Growth ◽

Temperature Solution

This paper reports the rapid synthesis, characterization, and photovoltaic and sensing applications of TiO2 nanoflowers prepared by a facile low-temperature solution process. The morphological characterizations clearly reveal the high-density growth of a three-dimensional flower-shaped structure composed of small petal-like rods. The detailed properties confirmed that the synthesized nanoflowers exhibited high crystallinity with anatase phase and possessed an energy bandgap of 3.2 eV. The synthesized TiO2 nanoflowers were utilized as photo-anode and electron-mediating materials to fabricate dye-sensitized solar cell (DSSC) and liquid nitroaniline sensor applications. The fabricated DSSC demonstrated a moderate conversion efficiency of ~3.64% with a maximum incident photon to current efficiency (IPCE) of ~41% at 540 nm. The fabricated liquid nitroaniline sensor demonstrated a good sensitivity of ~268.9 μA mM−1 cm−2 with a low detection limit of 1.05 mM in a short response time of 10 s.

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