Limits...
Visible and infrared emission from Si/Ge nanowires synthesized by metal-assisted wet etching.

Irrera A, Artoni P, Fioravanti V, Franzò G, Fazio B, Musumeci P, Boninelli S, Impellizzeri G, Terrasi A, Priolo F, Iacona F - Nanoscale Res Lett (2014)

Bottom Line: In particular, we prepared ultrathin Si/Ge NWs having a mean diameter of about 8 nm and lengths spanning from 1.0 to 2.7 μm.NW diameter is compatible with the occurrence of quantum confinement effects and, accordingly, we observed light emission assignable to the presence of Si and Ge nanostructures.PACS: 61.46.Km; 78.55.-m; 78.67.Lt.

View Article: PubMed Central - HTML - PubMed

Affiliation: IPCF CNR, viale F, Stagno d'Alcontres 37, Faro Superiore, Messina 98158, Italy. irrera@its.me.cnr.it.

ABSTRACT
Multi-quantum well Si/Ge nanowires (NWs) were realized by combining molecular beam epitaxy deposition and metal-assisted wet etching, which is a low-cost technique for the synthesis of extremely dense (about 1011 cm-2) arrays of NWs with a high and controllable aspect ratio. In particular, we prepared ultrathin Si/Ge NWs having a mean diameter of about 8 nm and lengths spanning from 1.0 to 2.7 μm. NW diameter is compatible with the occurrence of quantum confinement effects and, accordingly, we observed light emission assignable to the presence of Si and Ge nanostructures. We performed a detailed study of the photoluminescence properties of the NWs, with particular attention to the excitation and de-excitation properties as a function of the temperature and of the excitation photon flux, evaluating the excitation cross section and investigating the presence of non-radiative phenomena. PACS: 61.46.Km; 78.55.-m; 78.67.Lt.

No MeSH data available.


Related in: MedlinePlus

PL spectra of Si/Ge NWs. (a) Room temperature spectrum in the visible region. (b) Spectrum in the IR region obtained at 11 K. Both spectra were obtained with a photon flux of 3.1 × 1020 cm−2 · s−1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3928609&req=5

Figure 5: PL spectra of Si/Ge NWs. (a) Room temperature spectrum in the visible region. (b) Spectrum in the IR region obtained at 11 K. Both spectra were obtained with a photon flux of 3.1 × 1020 cm−2 · s−1.

Mentions: We studied the PL properties of the Si/Ge NWs having a length of 2.7 μm. In agreement with the extremely small diameter obtained, an intense room temperature PL coming from quantum-confined Si nanostructures occurs under a 488-nm excitation, as shown in Figure 5a; the PL spectrum consists of a broadband centered at about 670 nm which strongly resembles that one previously observed and reported for pure Si NWs [2,12]. A similar PL spectrum, although less intense, was observed in shorter NWs. No Ge-related PL signals are detected in the IR region at room temperature.


Visible and infrared emission from Si/Ge nanowires synthesized by metal-assisted wet etching.

Irrera A, Artoni P, Fioravanti V, Franzò G, Fazio B, Musumeci P, Boninelli S, Impellizzeri G, Terrasi A, Priolo F, Iacona F - Nanoscale Res Lett (2014)

PL spectra of Si/Ge NWs. (a) Room temperature spectrum in the visible region. (b) Spectrum in the IR region obtained at 11 K. Both spectra were obtained with a photon flux of 3.1 × 1020 cm−2 · s−1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3928609&req=5

Figure 5: PL spectra of Si/Ge NWs. (a) Room temperature spectrum in the visible region. (b) Spectrum in the IR region obtained at 11 K. Both spectra were obtained with a photon flux of 3.1 × 1020 cm−2 · s−1.
Mentions: We studied the PL properties of the Si/Ge NWs having a length of 2.7 μm. In agreement with the extremely small diameter obtained, an intense room temperature PL coming from quantum-confined Si nanostructures occurs under a 488-nm excitation, as shown in Figure 5a; the PL spectrum consists of a broadband centered at about 670 nm which strongly resembles that one previously observed and reported for pure Si NWs [2,12]. A similar PL spectrum, although less intense, was observed in shorter NWs. No Ge-related PL signals are detected in the IR region at room temperature.

Bottom Line: In particular, we prepared ultrathin Si/Ge NWs having a mean diameter of about 8 nm and lengths spanning from 1.0 to 2.7 μm.NW diameter is compatible with the occurrence of quantum confinement effects and, accordingly, we observed light emission assignable to the presence of Si and Ge nanostructures.PACS: 61.46.Km; 78.55.-m; 78.67.Lt.

View Article: PubMed Central - HTML - PubMed

Affiliation: IPCF CNR, viale F, Stagno d'Alcontres 37, Faro Superiore, Messina 98158, Italy. irrera@its.me.cnr.it.

ABSTRACT
Multi-quantum well Si/Ge nanowires (NWs) were realized by combining molecular beam epitaxy deposition and metal-assisted wet etching, which is a low-cost technique for the synthesis of extremely dense (about 1011 cm-2) arrays of NWs with a high and controllable aspect ratio. In particular, we prepared ultrathin Si/Ge NWs having a mean diameter of about 8 nm and lengths spanning from 1.0 to 2.7 μm. NW diameter is compatible with the occurrence of quantum confinement effects and, accordingly, we observed light emission assignable to the presence of Si and Ge nanostructures. We performed a detailed study of the photoluminescence properties of the NWs, with particular attention to the excitation and de-excitation properties as a function of the temperature and of the excitation photon flux, evaluating the excitation cross section and investigating the presence of non-radiative phenomena. PACS: 61.46.Km; 78.55.-m; 78.67.Lt.

No MeSH data available.


Related in: MedlinePlus