Physical mechanism for photon emissions from group-IV-semiconductor quantum-dots in quartz-glass and thermal-oxide layers

2021 ◽  
Author(s):  
Tomohisa Mizuno ◽  
Kohki Murakawa ◽  
Kazuma Yoshimizu ◽  
Takashi Aoki ◽  
Toshiyuki SAMESHIMA
Keyword(s):  
Quantum Dots ◽  
Quartz Glass ◽  
Group Iv ◽  
Semiconductor Quantum Dots ◽  
Implantation Technique ◽  
Dangling Bond ◽  
Impurity Density ◽  
Bond Density ◽  
Thermal Oxide ◽  
Group Iv Semiconductor

Abstract We experimentally studied the influence of both impurity density and dangling-bond density on PL emissions from group-IV-semiconductor quantum-dots (IV-QDs) of Si and SiC fabricated by hot-ion implantation technique, to improve the PL intensity (IPL) from IV-QDs embedded in two types of insulators of quartz glass (QZ) with low impurity density and thermal-oxide (OX) layers. First, we verified the IPL reduction in the IV-QDs in QZ. However, we demonstrated the IPL enhancement of IV-QDs in doped QZ, which is attributable to multiple-level emission owing to acceptor and donor ion implantations into QZ. Secondly, we confirmed the large IPL enhancement of IV-QDs in QZ and OX, owing to forming gas annealing with H2/N2 mixed gas, which are attributable to the reduction of the dangling-bond density in IV-QDs. Consequently, it is possible to improve the IPL of IV-QDs by increasing impurity density and reducing dangling-bond density.

Group-IV-semiconductor quantum-dots in thermal SiO2 layer fabricated by hot-ion implantation technique: different wavelength photon emissions

2021 ◽  
Vol 60 (SB) ◽  
pp. SBBK08
Author(s):  
Tomohisa Mizuno ◽  
Rikito Kanazawa ◽  
Kazuhiro Yamamoto ◽  
Kohki Murakawa ◽  
Kazuma Yoshimizu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Ion Implantation ◽  
Group Iv ◽  
Semiconductor Quantum Dots ◽  
Sio2 Layer ◽  
Implantation Technique ◽  
Group Iv Semiconductor

Formation of Direct Energy Gap Group IV Semiconductor Alloys and Quantum Dot Arrays in SnxSi1−x /Si and SnxGe1−x/Ge Alloy Systems

1999 ◽  
Vol 583 ◽  
Author(s):  
Harry A. Atwater ◽  
Regina Ragan ◽  
Kyu S. Min
Keyword(s):  
Quantum Dots ◽  
Phase Separation ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Energy Gap ◽  
Group Iv ◽  
Semiconductor Alloys ◽  
Group Iv Semiconductor ◽  
Direct Energy ◽  
Direct Energy Gap

AbstractThe narrow gap semiconductor alloys SnxGe1−x, and SnxSi1−x offer the possibility for engineering tunable direct energy gap Group IV semiconductor materials. For pseudomorphic SnxGe1−x, alloys grown on Ge (001) by molecular beam epitaxy, an indirect-to-direct bandgap transition with increasing Sn composition is observed, and the effects of misfit on the bandgap analyzed in terms of a deformation potential model. Key results are that pseudomorphic strain has only a very slight effect on the energy gap of SnxGe1−x, alloys grown on Ge (001) but for SnxGe1−x alloys grown on Ge (111) no indirect-to-direct gap transition is expected. In the SnxSi1−x system, ultrathin pseudomorphic epitaxially-stabilized α-SnxSi1−x alloys are grown on Si (001) substrates by conventional molecular beam epitaxy. Coherently strained oa-Sn quantum dots are formed within a defect-free Si (001) crystal by phase separation of the thin SnxSi1−x layers embedded in Si (001). Phase separation of the thin alloy film, and subsequent evolution occurs via growth and coarsening of regularly-shaped α-Sn quantum dots that appear as 4–6 nm diameter tetrakaidecahedra with facets oriented along elastically soft [100] directions. Attenuated total reflectance infrared absorption measurements indicate an absorption feature due to the α-Sn quantum dot array with onset at ˜0.3 eV and absorption strength of 8 × 103 cm−1, which are consistent with direct interband transitions.

MONTE CARLO SIMULATION OF THE KINETICS IN THE GROWTH OF SEMICONDUCTOR QUANTUM DOTS

2011 ◽  
Vol 25 (07) ◽  
pp. 465-471 ◽  
Author(s):  
CHANG ZHAO ◽  
M. ZHAO ◽  
Y. WANG ◽  
A. J. LV ◽  
G. M. WU ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Molecular Beam ◽  
Kinetic Monte Carlo ◽  
Semiconductor Quantum Dots ◽  
Dangling Bond ◽  
Good Qualitative Agreement ◽  
Kinetic Effects ◽  
Selection Of

By means of kinetic Monte Carlo simulation, which is based on the random selection of the surface hops of single adatom, we investigate the atoms' kinetics during the growth of the semiconductor quantum dots in a molecular beam epitaxy system, the deposition, diffusion and nucleation are considered as the main relevant processes during the growth of the quantum dots, taking into account the contribution of the dangling bond of the adatoms in the simulation. The dependence of the quantum dot size on the temperature and flux as well as the atomic kinetic effects are discussed in detail. The simulation results are in good qualitative agreement with those of the experiment.

Semiconductor Quantum Dots for Multicolor Fluorescence Imaging and Spectroscopy of Single Cancer Cells

2003 ◽  
Vol 773 ◽  
Author(s):  
Xiaohu Gao ◽  
Shuming Nie ◽  
Wallace H. Coulter
Keyword(s):  
Quantum Dots ◽  
Cancer Cells ◽  
Fluorescence Imaging ◽  
Organic Dyes ◽  
Fluorescent Proteins ◽  
Single Cells ◽  
Quantitative Imaging ◽  
Semiconductor Quantum Dots ◽  
Single Cancer ◽  
Imaging And Spectroscopy

AbstractLuminescent quantum dots (QDs) are emerging as a new class of biological labels with unique properties and applications that are not available from traditional organic dyes and fluorescent proteins. Here we report new developments in using semiconductor quantum dots for quantitative imaging and spectroscopy of single cancer cells. We show that both live and fixed cells can be labeled with multicolor QDs, and that single cells can be analyzed by fluorescence imaging and wavelength-resolved spectroscopy. These results raise new possibilities in cancer imaging, molecular profiling, and disease staging.

Hot Topic and Challenge of Semiconductor Quantum Dots as Fluorescence Labels*

2010 ◽  
Vol 37 (1) ◽  
pp. 103-110 ◽  
Author(s):  
Chang-Yan LI ◽  
Qian LI ◽  
Hai-Tao LIU ◽  
Jun ZHANG ◽  
DAMIRIN Aletangaole
Keyword(s):  
Quantum Dots ◽  
Semiconductor Quantum Dots
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