scholarly journals Optoelectric Properties of GaInP p-i-n Solar Cells with Different i-Layer Thicknesses

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Tsung-Shine Ko ◽  
Der-Yuh Lin ◽  
You-Chi He ◽  
Chen-Chia Kao ◽  
Bo-Yuan Hu ◽  
...  
Keyword(s):  
Solar Cells ◽  
Field Strength ◽  
Layer Thickness ◽  
Photoluminescence Spectrum ◽  
Layer Structure ◽  
Crystal Quality ◽  
Full Width ◽  
Half Maximum ◽  
Series Of Experiments ◽  
Layer I

The optoelectric properties of GaInP p-i-n solar cells with different intrinsic layer (i-layer) thicknesses from 0.25 to 1 μm were studied. Both emission intensity and full width at half maximum features of the photoluminescence spectrum indicate that the optimum i-layer thickness would be between 0.5 and 0.75 μm. The integrated current results of photocurrent experiment also point out that the samples with 0.5 to 0.75 μm i-layer thicknesses have optimum value around 156 nA. Electroreflectance measurements reveal that the built-in electric field strength of the sample gradually deviates from the theoretical value larger when i-layer thickness of the sample is thicker than 0.75 μm.I-Vmeasurements also confirm crystal quality for whole samples by obtaining the information about short currents of photovoltaic performances. A series of experiments reflect that thicker i-layer structure would induce more defects generation lowering crystal quality.

Towards Bulk-Like 3C-SiC Growth Using Low Off-Axis Substrates

2013 ◽  
Vol 740-742 ◽  
pp. 275-278
Author(s):  
Valdas Jokubavicius ◽  
Ho Hsuan Huang ◽  
Saskia Schimmel ◽  
Rickard Liljedahl ◽  
Rositza Yakimova ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Domain Size ◽  
Crystal Quality ◽  
Domain Formation ◽  
Full Width ◽  
Half Maximum ◽  
Temperature Ramp ◽  
Sublimation Method ◽  
Effects Of Temperature

Bulk-like 3C-SiC was grown on 1.2 degrees low off-axis 6H-SiC substrates using a sublimation epitaxy technique. The effects of temperature ramp-up and increase in layer thickness on the 3C-SiC domain formation were explored. The temperature ramp-up had no significant effect on the domain size. The domain size was considerably increased and the crystal quality was significantly improved by increasing the thickness of the layer towards bulk-like material. Average full width at half maximum values of 149 arcsec and 65 arcsec were measured in samples with thicknesses of 305 µm and 1080 µm, respectively, at a footprint of 1x3 mm2. This result implies that heteropeitaxial growth of 3C-SiC on low off-axis 6H-SiC substrates by a sublimation method can be used to prepare 3C-SiC seeds or can be further developed for growth of bulk 3C-SiC material.

scholarly journals Spectroscopic Studies of Laser-Based Far-Ultraviolet Plasma Light Source

2021 ◽  
Vol 11 (15) ◽  
pp. 6919
Author(s):  
Majid Masnavi ◽  
Martin Richardson
Keyword(s):  
Dense Plasma ◽  
Wavelength Region ◽  
Spectroscopic Studies ◽  
Radiation Hydrodynamics ◽  
Full Width ◽  
Half Maximum ◽  
Laser Plasmas ◽  
Series Of Experiments ◽  
Far Ultraviolet ◽  
Radiation Conversion

A series of experiments is described which were conducted to measure the absolute spectral irradiances of laser plasmas created from metal targets over the wavelength region of 123–164 nm by two separate 1.0 μm lasers, i.e., using 100 Hz, 10 ns, 2–20 kHz, 60–100 ns full-width-at-half-maximum pulses. A maximum radiation conversion efficiency of ≈ 3%/2πsr is measured over a wavelength region from ≈ 125 to 160 nm. A developed collisional-radiative solver and radiation-hydrodynamics simulations in comparison to the spectra detected by the Seya–Namioka-type monochromator reveal the strong broadband experimental radiations which mainly originate from bound–bound transitions of low-ionized charges superimposed on a strong continuum from a dense plasma with an electron temperature of less than 10 eV.

The Effect of Modified Crucible Design and Seed Attachment on SiC Crystal Grown by PVT

2013 ◽  
Vol 740-742 ◽  
pp. 77-80
Author(s):  
Jung Young Jung ◽  
Sang Il Lee ◽  
Mi Seon Park ◽  
Doe Hyung Lee ◽  
Hee Tae Lee ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Temperature Gradient ◽  
Single Crystals ◽  
Crystal Quality ◽  
Full Width ◽  
Half Maximum ◽  
Radial Temperature Gradient ◽  
Radial Temperature ◽  
Better Than

The present research was focused to investigate the effect of internal crucible design that influenced the 4H-SiC crystal growth onto a 6H-SiC seed by PVT method. The crucible design was modified to produce a uniform radial temperature gradient in the growth cell. The seed attachment was also modified with a use of polycrystalline SiC plate. The crystal quality of 4H-SiC single crystals grown in modified crucible and grown with modified seed attachment was revealed to be better than that of crystal grown in conventional crucible. The full width at half maximum (FWHM) values of grown SiC crystals in the conventional crucible, the modified seed attachment and the modified crucible were 285 arcsec, 134 arcsec and 128 arcsec, respectively. The micropipe density (MPD) of grown SiC crystals in the conventional crucible, the modified seed attachment and the modified crucible were 101ea/cm^2, 81ea/cm^2 and 42ea/cm^2, respectively.

A review of Schottky and cold field-emission cathode characteristics

1994 ◽  
Vol 52 ◽  
pp. 938-939
Author(s):  
L. W. Swanson
Keyword(s):  
Field Strength ◽  
Field Emission ◽  
Full Width ◽  
Half Maximum ◽  
Continuous Change ◽  
Field Emission Cathode ◽  
High Brightness ◽  
Surface Electric Field ◽  
Electron Focusing ◽  
Emission Cathode

Two high brightness, point cathodes currently being used in TEM's and nanometer electron focusing systems are the cold field emission (CFE) and Schottky emission (SE) cathodes. In terms of emission mechanisms, CFE and SE represent two extremes of a continuous change in surface electric field strength F and temperature T of a pointed cathode of work function ϕ. The conditions for CFE and SE emission modes can be stated as follows:CFE: 4π(2mϕ(1/2 kT/heF < 0.5SE: he1/4F3/42<2m1/2 < 0.5When the above conditions are met most electrons are tunnelling from at or near the Fermi level inthe case of CFE and thermally excited over the vacuum barrier in the case of SE. The expressions for the current density J are:CFE: JCFE = a(F2/ϕ)exp(10.4/ϕ1/2)exp(-bϕ3/2/F)(A/cm2SE: JSE = 1202exp(-(ϕ - 3.8F1/2)/)kT)(A/cm2)where a = 1.54×10-6, b = 0.644 and F and ϕ are in units of V/Å and eV respectively.One important aspect for source optics applications is the energy spread of the emitted electrons for the two emission regimes. Fig. 1 gives the theoretical values of the full width at half maximum (FWHM) of the energy distribution for the case of CFE with ϕ = 4.0 eV, T = 300 K, J = 1×105 A/cm2 and SE with ϕ = 3.0 eV, T = 1800, J = 1×103 A/cm2.

Epitaxial growth of (010)-oriented β-FeSi2 film on Si(110) substrate

2013 ◽  
Vol 1493 ◽  
pp. 189-194 ◽  
Author(s):  
Kensuke Akiyama ◽  
Hiroshi Funakubo ◽  
Masaru Itakura
Keyword(s):  
Thin Layer ◽  
Epitaxial Growth ◽  
Photoluminescence Spectrum ◽  
Lattice Strain ◽  
Lattice Parameter ◽  
Silver Layer ◽  
Full Width ◽  
Half Maximum ◽  
High Quality ◽  
Rocking Curve

ABSTRACTHigh-quality (010)-oriented epitaxial β-FeSi2 films were grown on Si(110) substrates by coating silver thin layer. The full width at half maximum of the rocking curve of β-FeSi2040 was 0.14o for the film deposited at 800°C on Si(110) substrates with 95 nm-thick silver layer. Moreover, this epitaxial β-FeSi2 film was constructed with single domain structure, and the lattice parameter of a-axis was extended by 0.7%. The photoluminescence spectrum from this epitaxial β-FeSi2 indicated that the band-gap was modulated by lattice strain of a-axis.

ATOMIC ENVIRONMENT IN LEAD-BISMUTHATE GLASSES CONTAINING MANGANESE

2003 ◽  
Vol 17 (07) ◽  
pp. 291-301 ◽  
Author(s):  
V. SIMON ◽  
H. BAKO-SZILAGYI ◽  
M. NEUMANN ◽  
S. G. CHIUZBĂIAN ◽  
S. SIMON
Keyword(s):  
Heat Treatment ◽  
Electronic Structure ◽  
Field Strength ◽  
Structural Changes ◽  
Full Width ◽  
Half Maximum ◽  
X Ray ◽  
Gaussian Functions ◽  
Intermediate Range ◽  
Simulation Based

The atomic environment of 20MnO · 80(x Bi 2 O 3 · y PbO ) glass samples having the ratio of bismuth to lead atoms of 8:1 and 3:1 was investigated with respect to the thermal induced structural changes, cationic field strength and electronic structure of the compound. The position and full width at half maximum of X-ray photoelectron peaks were estimated using spectra simulation based on the summation of Lorentzian and Gaussian functions. Data obtained from XPS core-level spectra Bi 4f, Pb 4f, Mn 2p, and O 1s indicate a reduction of glass disorder both by heat treatment and by increasing the PbO content in the samples. The cations behave essentially as network formers that could be correlated with an intermediate range structure.

Analysis on 3C-SiC Layer Grown on Pseudomorphic-Si/Si1-xGex/Si(001) Heterostructures

2014 ◽  
Vol 806 ◽  
pp. 21-25 ◽  
Author(s):  
Nicolo’ Piluso ◽  
Massimo Camarda ◽  
Ruggero Anzalone ◽  
Andrea Severino ◽  
Silvia Scalese ◽  
...  
Keyword(s):  
Stress Relaxation ◽  
Thin Layer ◽  
Raman Spectra ◽  
Lattice Parameter ◽  
Crystal Quality ◽  
Raman Mode ◽  
Full Width ◽  
Half Maximum ◽  
Raman Characterization

Micro Raman characterization has been used to determine the stress status of 3C-SiC epilayer grown on pseudomorphic-Si thin layer on Si1-xGex/Si(001). The strain conditions of the Si1-xGexfilms grown on Si(001) have been determined by the analysis of additional Silicon Raman peaks, which Raman shifts are related to the lattice parameter. Through the analysis of the Raman spectra, the correlation between the Si1-xGexfilm, the crystal quality and the stress relaxation of the 3C-SiC as a function of the Germanium fraction (x), have been evaluated. The increase of Germanium fraction determines the reduction of the voids density located at the 3C-SiC/Si interface and the relaxation of the stress within the epilayer. Moreover, the 3C-SiC crystal quality, monitored by the Full Width at Half Maximum of the TO Raman mode, remains unchanged for any Germanium fraction values.

Study of the Zeeman Effect of Er3+ in GaAs:Er,O

1996 ◽  
Vol 422 ◽  
Author(s):  
Dieter Haase ◽  
Achim Dörnen ◽  
Kenichiro Takahei ◽  
Akihito Taguchi
Keyword(s):  
Photoluminescence Spectrum ◽  
Optical Transition ◽  
Zeeman Effect ◽  
Full Width ◽  
Half Maximum ◽  
Monoclinic Symmetry ◽  
Organic Vapor ◽  
Rhombic Symmetry ◽  
Metal Organic ◽  
Low Symmetry

AbstractWe analyze the Zeeman effect of the 4/13/2 → 4/15/2 transition of Er3+ in GaAs:Er,O grown by metal-organic vapor-phase epitaxy. The photoluminescence spectrum has been assigned previously to one specific Er-O complex. The dominant optical transition at 1538 nm (6499.5 cm−1), which shows a full width at half maximum of only 0.05 cm−1, has been investigated by high-resolution Zeeman spectroscopy. A highly anisotropic Zeeman pattern is found which indicates the low symmetry of the underlying complex. A detailed analysis shows that the defect has a predominant rhombic symmetry C2v,. Additionally, smaller contributions of a crystal field with a monoclinic symmetry Clh are found. The results provide further arguments that an ErO2 complex is the responsible center observed.

scholarly journals InP nanowires quality control using SEM and Raman spectroscopy

2016 ◽  
Vol 34 (4) ◽  
pp. 851-855
Author(s):  
K. Grodecki ◽  
E. Dumiszewska ◽  
M. Romaniec ◽  
W. Strupinski
Keyword(s):  
Raman Spectroscopy ◽  
Low Energy ◽  
Crystal Quality ◽  
Full Width ◽  
Half Maximum ◽  
Sem Images ◽  
Different Types ◽  
Si Doped ◽  
Scanning Electron

AbstractThree different types of samples of InP nanowires, i.e. undoped, doped with Si and doped with Te, were grown and measured using SEM and Raman spectroscopy. Scanning Electron Microscope (SEM) images showed differences in the length, homogeneity and curvature of the nanowires. The most homogenous wires, grown most perpendicular to the surface, were those Si doped. They were also the shortest. Raman spectroscopy showed that the nanowires doped with Si had the lowest Full Width at Half Maximum (FWHM) TO band, which suggests the highest crystal quality of these wires. For the wires doped with Te, which were the most inhomogeneous, a low energy acoustic band was also observed, which suggests the lowest crystal quality of these structures.

scholarly journals Influence of the Active Layer Structure on the Photovoltaic Performance of Water-Soluble Polythiophene-Based Solar Cells

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1640
Author(s):  
Massimiliano Lanzi ◽  
Debora Quadretti ◽  
Martina Marinelli ◽  
Yasamin Ziai ◽  
Elisabetta Salatelli ◽  
...  
Keyword(s):  
Solar Cells ◽  
Layer Structure ◽  
Photovoltaic Performance ◽  
Phase Segregation ◽  
Water Soluble ◽  
Polymerization Reaction ◽  
Fullerene Derivative ◽  
C60 Fullerene ◽  
Photovoltaic Efficiency ◽  
Single Material

A new side-chain C60-fullerene functionalized thiophene copolymer bearing tributylphosphine-substituted hexylic lateral groups was successfully synthesized by means of a fast and effective post-polymerization reaction on a regioregular ω-alkylbrominated polymeric precursor. The growth of the polymeric intermediate was followed by NMR spectrometry in order to determine the most convenient reaction time. The obtained copolymer was soluble in water and polar solvents and was used as a photoactive layer in single-material organic photovoltaic (OPV) solar cells. The copolymer photovoltaic efficiency was compared with that of an OPV cell containing a water-soluble polythiophenic homopolymer, functionalized with the same tributylphosphine-substituted hexylic side chains, in a blend with a water-soluble C60-fullerene derivative. The use of a water-soluble double-cable copolymer made it possible to enhance the control on the nanomorphology of the active blend, thus reducing phase-segregation phenomena, as well as the macroscale separation between the electron acceptor and donor components. Indeed, the power conversion efficiency of OPV cells based on a single material was higher than that obtained with the classical architecture, involving the presence of two distinct ED and EA materials (PCE: 3.11% vs. 2.29%, respectively). Moreover, the synthetic procedure adopted to obtain single material-based cells is more straightforward and easier than that used for the preparation of the homopolymer-based BHJ solar cell, thus making it possible to completely avoid the long synthetic pathway which is required to prepare water-soluble fullerene derivatives.

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