scholarly journals Fabrication of Graphene-Metal Transparent Conductive Nanocomposite Layers for Photoluminescence Enhancement

Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1037
Author(s):  
Hongyong Huang ◽  
Zhiyou Guo ◽  
Sitong Feng ◽  
Huiqing Sun ◽  
Shunyu Yao ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Electron Mobility ◽  
Single Layer Graphene ◽  
Multiple Quantum ◽  
Preparation Technique ◽  
High Electron ◽  
Conductive Layer ◽  
Ag Nps ◽  
Layer Graphene ◽  
Transparent Conductive Layer

In this work, the synthesis and characterization ofgraphene-metal nanocomposite, a transparent conductive layer, is examined. This transparent conductive layer is named graphene-Ag-graphene (GAG), which makes full use of the high electron mobility and high conductivity characteristics of graphene, while electromagnetically induced transparency (EIT) is induced by Ag nanoparticles (NPs). The nanocomposite preparation technique delivers three key parts including the transfer of the first layer graphene, spin coating of Ag NPs and transfer of the second layer of graphene. The GAG transparent conductive nanocomposite layer possess a sheet resistance of 16.3 ohm/sq and electron mobility of 14,729 cm2/(v s), which are superior to single-layer graphene or other transparent conductive layers. Moreover, the significant enhancement of photoluminescence can be ascribed to the coupling of the light emitters in multiple quantum wells with the surface plasmon Ag NPs and the EIT effect.

Bandstructure Near Misfit Dislocations in Si Quantum Wells

1998 ◽  
Vol 4 (S2) ◽  
pp. 794-795
Author(s):  
P.E. Batson
Keyword(s):  
Quantum Wells ◽  
Conduction Band ◽  
Electron Mobility ◽  
Axial Strain ◽  
Strain Relaxation ◽  
Local Potential ◽  
Misfit Dislocations ◽  
High Electron ◽  
Strained Si ◽  
Growth Interface

High electron mobility structures have been built for several years now using strained silicon layers grown on SixGe(1-x) with x in the 25-40% range. In these structures, a thin layer of silicon is grown between layers of unstrained GeSi alloy. Matching of the two lattices in the plane of growth produces a bi-axial strain in the silicon, splitting the conduction band and providing light electron levels for enhanced mobility. If the silicon channel becomes too thick, strain relaxation can occur by injection of misfit dislocations at the growth interface between the silicon and GeSi alloy. The strain field of these dislocations then gives rise to a local potential variation that limits electron mobility in the strained Si channel. This study seeks to verify this mechanism by measuring the absolute conduction band shifts which track the local potential near the misfit dislocations.

scholarly journals Особенности ионизации доноров кремния и рассеяние электронов в псевдоморфных квантовых ямах AlGaAs/InGaAs/GaAs при сильном одностороннем delta-легировании

2018 ◽  
Vol 44 (4) ◽  
pp. 34
Author(s):  
Д.А. Сафонов ◽  
А.Н. Виниченко ◽  
Н.И. Каргин ◽  
И.С. Васильевский
Keyword(s):  
Electron Transport ◽  
Quantum Wells ◽  
Transport Properties ◽  
Electron Mobility ◽  
High Electron ◽  
High Electron Mobility ◽  
Dimensional Quantization ◽  
Spacer Layer ◽  
Electron Transport Properties ◽  
Nonmonotonic Variation

AbstractThe influence of the concentration of silicon donors on the electron-transport properties of pseudomorphous Al_0.25Ga_0.75As/In_0.2Ga_0.8As/GaAs quantum wells (QWs) in heterostructures with heavy unilateral δ-doping by Si atoms was studied in a broad temperature interval (2.1–300 K). High electron mobility (up to 35700 cm^2/(V s)) at T = 4.2 K was observed at a 2D (sheet) electron density of 2 × 10^12 cm^–2 in the QW. A band mechanism limiting the ionization of donors at an increased level of doping is described. The nonmonotonic variation of electron mobility with increasing silicon concentration is explained. A growth in the mobility is related to increase in the Fermi momentum and screening, while the subsequent decay is caused by tunneling-induced degradation of the spacer layer with decreasing potential of the conduction band in the region of δ-Si layer. It is shown that the effect is not related to filling of the upper subband of dimensional quantization.

Reduction of microtwin defects for high-electron-mobility InSb quantum wells

2007 ◽  
Vol 91 (6) ◽  
pp. 062106 ◽  
Author(s):  
T. D. Mishima ◽  
M. Edirisooriya ◽  
M. B. Santos
Keyword(s):  
Quantum Wells ◽  
Electron Mobility ◽  
High Electron ◽  
High Electron Mobility

Electron mobility enhancement by confining optical phonons in GaAs/AlAs multiple quantum wells

1992 ◽  
Vol 60 (17) ◽  
pp. 2141-2143 ◽  
Author(s):  
X. Theodore Zhu ◽  
Herbert Goronkin ◽  
George N. Maracas ◽  
Ravi Droopad ◽  
Michael A. Stroscio
Keyword(s):  
Quantum Wells ◽  
Electron Mobility ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
Optical Phonons

scholarly journals Электронный квантовый транспорт в псевдоморфных и метаморфных квантовых ямах на основе In-=SUB=-0.2-=/SUB=-Ga-=SUB=-0.8-=/SUB=-As

2019 ◽  
Vol 53 (3) ◽  
pp. 359
Author(s):  
А.Н. Виниченко ◽  
Д.А. Сафонов ◽  
Н.И. Каргин ◽  
И.С. Васильевский
Keyword(s):  
Quantum Wells ◽  
Electron Mobility ◽  
High Electron Mobility Transistor ◽  
Structural Defects ◽  
High Electron ◽  
Scattering Mechanism ◽  
Metamorphic Buffer ◽  
Angle Scattering ◽  
Hemt Structure ◽  
First Time

AbstractMetamorphic high-electron-mobility transistor (HEMT) structures based on deep In_0.2Ga_0.8As/In_0.2Al_0.8As quantum wells (0.7 eV for Γ electrons) with different metamorphic buffer designs are implemented and investigated for the first time. The electronic properties of metamorphic and pseudomorphic HEMT structures with the same doping are compared. It is found that, over a temperature range of 4–300 K, both the electron mobility and concentration in the HEMT structure with a linear metamorphic buffer are higher than those in the pseudomorphic HEMT structure due to an increase in the depth of the quantum well. Low-temperature magnetotransport measurements demonstrate that the quantum momentum-relaxation time decreases considerably in metamorphic HEMT structures because of enhanced small-angle scattering resulting from structural defects and inhomogeneities, while the dominant scattering mechanism in structures of both types is still due to remote ionized impurities.

Atomic and electronic structure of a 60° misfit dislocation

1995 ◽  
Vol 53 ◽  
pp. 276-277
Author(s):  
P.E. Batson
Keyword(s):  
Quantum Wells ◽  
Electron Mobility ◽  
Lattice Mismatch ◽  
High Mobility ◽  
Misfit Dislocations ◽  
High Electron ◽  
Strained Si ◽  
Electron Conduction ◽  
Thick Layers ◽  
Atomic And Electronic Structure

Strained Si quantum wells provide high electron mobility channels for devices within the standard Si-based technology. These wells consist of 8-12nm thick layers, epitaxially grown over relaxed Si-Ge alloys. The 1.4% lattice mismatch between Si and a Ge40Si60 alloy produces a Si layer strained in tension in the plane of the layer and in compression in the direction perpendicular to the layer, splitting the Si conduction band into a higher energy four-fold degenerate band and a lower energy two-fold degenerate band. The latter band is a high mobility channel for electron conduction. If the Si layer is made thicker than the critical thickness for epitaxy, misfit dislocations result to accommodate the strain. For growth of Si on (001) Ge40Si60 these are of the 60° type, dissociated into a 30° partial dislocation at the Si/alloy interface, a 90° partial some tens of Angstroms away in the alloy, and a connecting stacking fault. In the presence of this strain relieving structure, the electron mobility is degraded.

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