Records |
Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
Title |
Ballistic current in metal-oxide-semiconductor field-effect transistors: the role of device topology |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
106 |
Issue |
5 |
Pages |
053702,1-053702,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this study we investigate the effect of device topology on the ballistic current in n-channel metal-oxide-semiconductor field-effect transistors. Comparison of the nanoscale planar and double-gate devices reveals that, down to a certain thickness of the double gate film, the ballistic current flowing in the double gate device is twice as large compared to its planar counterpart. On the other hand, further thinning of the film beyond this threshold is found to change noticeably the confinement and transport characteristics, which are strongly depending on the film material and the surface orientation. For double gate Ge and Si devices there exists a critical film thickness below which the transverse gate field is no longer effectively screened by the inversion layer electron gas and mutual inversion of the two gates is turned on. In the case of GaAs and other similar IIIV compounds, a decrease in the film thickness may drastically change the occupation of the L-valleys and therefore amend the transport properties. The simulation results show that, in both cases, the ballistic current and the transconductance are considerably enhanced. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000269850300052 |
Publication Date |
2009-09-03 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
Call Number |
UA @ lucian @ c:irua:79744 |
Serial |
214 |
Permanent link to this record |
|
|
|
Author |
Buffière, M.; Zaghi, A.E.; Lenaers, N.; Batuk, M.; Khelifi, S.; Drijkoningen, J.; Hamon, J.; Stesmans, A.; Kepa, J.; Afanas’ev, V.V.; Hadermann, J.; D’Haen, J.; Manca, J.; Vleugels, J.; Meuris, M.; Poortmans, J.; |
Title |
Effect of binder content in Cu-In-Se precursor ink on the physical and electrical properties of printed CuInSe2 solar cells |
Type |
A1 Journal article |
Year |
2014 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
118 |
Issue |
47 |
Pages |
27201-27209 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Printed chalcopyrite thin films have attracted considerable attention in recent years due to their potential in the high-throughput production of photovoltaic devices. To improve the homogeneity of printed CuInSe2 (CISe) layers, chemical additives such as binder can be added to the precursor ink. In this contribution, we investigate the influence of the dicyandiamide (DCDA) content, used as a binder in the precursor ink, on the physical and electrical properties of printed CISe solar cells. It is shown that the use of the binder leads to a dense absorber, composed of large CISe grains close to the surface, while the bulk of the layer consists of CISe crystallites embedded in a CuxS particle based matrix, resulting from the limited sintering of the precursor in this region. The expected additional carbon contamination of the CISe layer due to the addition of the binder appears to be limited, and the optical properties of the CISe layer are similar to the reference sample without additive. The electrical characterization of the corresponding CISe/CdS solar cells shows a degradation of the efficiency of the devices, due to a modification in the predominant recombination mechanisms and a limitation of the space charge region width when using the binder; both effects could be explained by the inhomogeneity of the bulk of the CISe absorber and high defect density at the CISe/CuxS-based matrix interface. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000345722400003 |
Publication Date |
2014-11-06 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.536; 2014 IF: 4.772 |
Call Number |
UA @ lucian @ c:irua:121332 |
Serial |
801 |
Permanent link to this record |
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|
|
Author |
E. Zaghi, A.; Buffière, M.; Koo, J.; Brammertz, G.; Batuk, M.; Verbist, C.; Hadermann, J.; Kim, W.K.; Meuris, M.; Poortmans, J.; Vleugels, J.; |
Title |
Effect of selenium content of CuInSex alloy nanopowder precursors on recrystallization of printed CuInSe2 absorber layers during selenization heat treatment |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
|
Issue |
|
Pages |
1-7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Polycrystalline CuInSe2 semiconductors are efficient light absorber materials for thin film solar cell technology, whereas printing is one of the promising low cost and non-vacuum approaches for the fabrication of thin film solar cells. The printed precursors are transformed into a dense polycrystalline CuInSe2 semiconductor film via thermal treatment in ambient selenium atmosphere (selenization). In this study, the effect of the selenium content in high purity mechanically synthesized CuInSex (x = 2, 1.5, 1 or 0.5) alloy precursors on the recrystallization of the CuInSe2 phase during the selenization process was investigated. The nanostructure and phase variation of CuInSex nanopowders were investigated by different characterization techniques. The recrystallization process of the 12 μm thick CuInSex coatings into the CuInSe2 phase during selenization in selenium vapor was investigated via in-situ high temperature X-ray diffraction. The CuInSex precursors with lower selenium content showed a more pronounced phase conversion into CuInSe2 compared to the higher selenium content CuInSex precursors. Moreover, the CuInSex (x = 0.5 and 1) precursor resulted in a denser polycrystalline CuInSe2 semiconductor film with larger crystals. This could be attributed to a more intensive atomic interdiffusion within the CuInSex precursor system compared to a CuInSe2 phase precursor, and the formation of intermediate CuSe and CuSe2 fluxing phases during selenization. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000352225900004 |
Publication Date |
2014-10-13 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.879; 2014 IF: 1.759 |
Call Number |
c:irua:121330 |
Serial |
834 |
Permanent link to this record |
|
|
|
Author |
Batuk, M.; Buffiere, M.; Zaghi, A.E.; Lenaers, N.; Verbist, C.; Khelifi, S.; Vleugels, J.; Meuris, M.; Hadermann, J. |
Title |
Effect of the burn-out step on the microstructure of the solution-processed Cu(In,Ga)Se2 solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
583 |
Issue |
583 |
Pages |
142-150 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
For the development of the photovoltaic industry cheap methods for the synthesis of Cu(In,Ga)Se-2 (CIGSe) based solar cells are required. In this work, CIGSe thin films were obtained by a solution-based method using oxygen-bearing derivatives. With the aimof improving the morphology of the printed CIGSe layers, we investigated two different annealing conditions of the precursor layer, consisting of (1) a direct selenization step (reference process), and (2) a pre-treatment thermal step prior to the selenization. We showed that the use of an Air/H2S burn-out step prior to the selenization step increases the CIGSe grain size and reduces the carbon content. However, it leads to the reduction of the solar cell efficiency from 4.5% in the reference sample down to 0.5% in the annealed sample. Detailed transmission electron microscopy analysis, including high angle annular dark field scanning transmission electron microscopy and energy dispersive X-ray mapping, was applied to characterize the microstructure of the film and to determine the relationship between microstructure and the solar cell performance. We demonstrated that the relatively low efficiency of the reference solar cells is related not only to the nanosize of the CIGSe grains and presence of the pores in the CIGSe layer, but also to the high amount of secondary phases, namely, In/Ga oxide (or hydroxide) amorphous matter, residuals of organicmatter (carbon), and copper sulfide that is formed at the CIGSe/MoSe2 interface. The annealing in H2S during the burn-out step leads to the formation of the copper sulfide at all grain boundaries and surfaces in the CIGSe layer, which results in the noticeably efficiency drop. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000353812400024 |
Publication Date |
2015-04-05 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
Call Number |
c:irua:126009 |
Serial |
845 |
Permanent link to this record |
|
|
|
Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; de Meyer, K.; Meuris, M.; Heyns, M. |
Title |
General 2D Schrödinger-Poisson solver with open boundary conditions for nano-scale CMOS transistors |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
Volume |
7 |
Issue |
4 |
Pages |
475-484 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Employing the quantum transmitting boundary (QTB) method, we have developed a two-dimensional Schrödinger-Poisson solver in order to investigate quantum transport in nano-scale CMOS transistors subjected to open boundary conditions. In this paper we briefly describe the building blocks of the solver that was originally written to model silicon devices. Next, we explain how to extend the code to semiconducting materials such as germanium, having conduction bands with energy ellipsoids that are neither parallel nor perpendicular to the channel interfaces or even to each other. The latter introduces mixed derivatives in the 2D effective mass equation, thereby heavily complicating the implementation of open boundary conditions. We present a generalized quantum transmitting boundary method that mainly leans on the completeness of the eigenstates of the effective mass equation. Finally, we propose a new algorithm to calculate the chemical potentials of the source and drain reservoirs, taking into account their mutual interaction at high drain voltages. As an illustration, we present the potential and carrier density profiles obtained for a (111) Ge NMOS transistor as well as the ballistic current characteristics. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
000209032500002 |
Publication Date |
2008-09-02 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1569-8025;1572-8137; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.526 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.526; 2008 IF: NA |
Call Number |
UA @ lucian @ c:irua:89505 |
Serial |
1322 |
Permanent link to this record |
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|
|
Author |
Brammertz, G.; Oueslati, S.; Buffiere, M.; Bekaert, J.; El Anzeery, H.; Messaoud, K.B.; Sahayaraj, S.; Nuytten, T.; Koble, C.; Meuris, M.; Poortmans, J.; |
Title |
Investigation of properties limiting efficiency in Cu2ZnSnSe4-based solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
IEEE journal of photovoltaics |
Abbreviated Journal |
Ieee J Photovolt |
Volume |
5 |
Issue |
5 |
Pages |
649-655 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We have investigated different nonidealities in Cu2ZnSnSe4CdSZnO solar cells with 9.7% conversion efficiency, in order to determine what is limiting the efficiency of these devices. Several nonidealities could be observed. A barrier of about 300 meV is present for electron flow at the absorberbuffer heterojunction leading to a strong crossover behavior between dark and illuminated currentvoltage curves. In addition, a barrier of about 130 meV is present at the Moabsorber contact, which could be reduced to 15 meV by inclusion of a TiN interlayer. Admittance spectroscopy results on the devices with the TiN backside contact show a defect level with an activation energy of 170 meV. Using all parameters extracted by the different characterization methods for simulations of the two-diode model including injection and recombination currents, we come to the conclusion that our devices are limited by the large recombination current in the depletion region. Potential fluctuations are present in the devices as well, but they do not seem to have a special degrading effect on the devices, besides a probable reduction in minority carrier lifetime through enhanced recombination through the band tail defects. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000353524800026 |
Publication Date |
2014-12-19 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2156-3381;2156-3403; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.712 |
Times cited |
13 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.712; 2015 IF: 3.165 |
Call Number |
c:irua:123717 |
Serial |
1734 |
Permanent link to this record |
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|
|
Author |
Buffière, M.; Brammertz, G.; Sahayaraj, S.; Batuk, M.; Khelifi, S.; Mangin, D.; El Mel, A.A.; Arzel, L.; Hadermann, J.; Meuris, M.; Poortmans, J.; |
Title |
KCN chemical etch for interface engineering in Cu2ZnSnSe4 solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
14690-14698 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The removal of secondary phases from the surface of the kesterite crystals is one of the major challenges to improve the performances of Cu2ZnSn(S,Se)(4) (CZTSSe) thin film solar cells. In this Contribution, the KCN/KOH Chemical etching approach, originally developed for the removal of CuxSe phases in Cu(In,Ga)(S,Se)(2) thin films) is applied to CZTSe absorbers exhibiting various chemical compositions. Two distinct electrical behaviors were observed on CZTSe/CdS solar cells after treatment: (i) the improvement of the fill factor (FF) after 30 s of etching for the CZTSe absorbers showing initially a distortion of the electrical characteristic; (ii) the progressive degradation Of the FF after long treatment time for all Cu-poor CZTSe solar cell samples. The first effect can be attributed to the action of KCN on the absorber, that is found to clean the absorber free surface from most of the secondary phases surrounding the kesterite grains (e.g., Se-0, CuxSe, SnSex, SnO2, Cu2SnSe3 phases, excepting the ZnSe-based phases). The second observation was identified as a consequence of the preferential etching of Se, Sn, and Zn from the CZTSe surface by the KOH solution, combined with the modification of the alkali content of the absorber. The formation of a Cu-rich shell at the absorber/buffer layer interface, leading to the increase of the recombination rate at the interface, and the increase in the doping of the absorber layer after etching are found to be at the origin of the deterioration of the FF of the solar cells. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000358395200019 |
Publication Date |
2015-06-03 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.504 |
Times cited |
34 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
c:irua:127153 |
Serial |
1755 |
Permanent link to this record |
|
|
|
Author |
Zaghi, A.E.; Buffière, M.; Brammertz, G.; Batuk, M.; Lenaers, N.; Kniknie, B.; Hadermann, J.; Meuris, M.; Poortmans, J.; Vleugels, J. |
Title |
Mechanical synthesis of high purity Cu-In-Se alloy nanopowder as precursor for printed CISe thin film solar cells |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Advanced powder technology |
Abbreviated Journal |
Adv Powder Technol |
Volume |
25 |
Issue |
4 |
Pages |
1254-1261 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Mechanical alloying and ball milling are low cost, up-scalable techniques for the preparation of high purity chalcogenide nanopowders to be used as precursor material for printing thin film solar cells. In this study, high purity copper indium selenium (Cu-In-Se) alloy nanopowders with 20-200 nm particle size were synthesized from macroscopic elemental Cu, In and Se powders via mechanical alloying and planetary ball milling. The particle size distribution, morphology, composition, and purity level of the synthesized Cu-In-Se alloy nanopowders were investigated. Thin Cu-In-Se alloy nanopowder ink coatings, deposited on Mo-coated glass substrates by doctor blading, were converted into a CuInSe2 semiconductor film by selenization heat treatment in Se vapor. The CuInSe2 film showed semiconducting band gap around 1 eV measured by photoluminescence spectroscopy. CuInSe2 absorber layer based thin film solar cell devices were fabricated to assess their performance. The solar cell device showed a total efficiency of 4.8%, as measured on 0.25 cm(2) area cell. (c) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Zeist |
Editor |
|
Language |
|
Wos |
000341871700015 |
Publication Date |
2014-03-17 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-8831; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.659 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.659; 2014 IF: 2.638 |
Call Number |
UA @ lucian @ c:irua:119896 |
Serial |
1977 |
Permanent link to this record |
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|
|
Author |
Buffière, M.; Brammertz, G.; Batuk, M.; Verbist, C.; Mangin, D.; Koble, C.; Hadermann, J.; Meuris, M.; Poortmans, J. |
Title |
Microstructural analysis of 9.7% efficient Cu2ZnSnSe4 thin film solar cells |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
105 |
Issue |
18 |
Pages |
183903 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This work presents a detailed analysis of the microstructure and the composition of our record Cu 2ZnSnSe4 (CZTSe)-CdS-ZnO solar cell with a total area efficiency of 9.7%. The average composition of the CZTSe crystallites is Cu 1.94 Zn 1.12Sn0.95Se3.99. Large crystals of ZnSe secondary phase (up to 400 nm diameter) are observed at the voids between the absorber and the back contact, while smaller ZnSe domains are segregated at the grain boundaries and close to the surface of the CZTSe grains. An underlying layer and some particles of Cu xSe are observed at the Mo-MoSe2-Cu2ZnSnSe4 interface. The free surface of the voids at the back interface is covered by an amorphous layer containing Cu, S, O, and C, while the presence of Cd, Na, and K is also observed in this region. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000345000000086 |
Publication Date |
2014-11-08 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951;1077-3118; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.411; 2014 IF: 3.302 |
Call Number |
UA @ lucian @ c:irua:121329 |
Serial |
2038 |
Permanent link to this record |
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|
|
Author |
Zhang, Y.; Fischetti, M.V.; Sorée, B.; Magnus, W.; Heyns, M.; Meuris, M. |
Title |
Physical modeling of strain-dependent hole mobility in Ge p-channel inversion layers |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
106 |
Issue |
8 |
Pages |
083704,1-083704,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present comprehensive calculations of the low-field hole mobility in Ge p-channel inversion layers with SiO2 insulator using a six-band k·p band-structure model. The cases of relaxed, biaxially, and uniaxially (both tensily and compressively) strained Ge are studied employing an efficient self-consistent methodmaking use of a nonuniform spatial mesh and of the Broyden second methodto solve the coupled envelope-wave function k·p and Poisson equations. The hole mobility is computed using the KuboGreenwood formalism accounting for nonpolar hole-phonon scattering and scattering with interfacial roughness. Different approximations to handle dielectric screening are also investigated. As our main result, we find a large enhancement (up to a factor of 10 with respect to Si) of the mobility in the case of uniaxial compressive stress similarly to the well-known case of Si. Comparison with experimental data shows overall qualitative agreement but with significant deviations due mainly to the unknown morphology of the rough Ge-insulator interface, to additional scattering with surface optical phonon from the high- insulator, to Coulomb scattering interface traps or oxide chargesignored in our calculationsand to different channel structures employed. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000271358100050 |
Publication Date |
2009-10-20 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
29 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
Call Number |
UA @ lucian @ c:irua:80137 |
Serial |
2617 |
Permanent link to this record |
|
|
|
Author |
Buffière, M.; Brammertz, G.; Oueslati, S.; El Anzeery, H.; Bekaert, J.; Ben Messaoud, K.; Köble, C.; Khelifi, S.; Meuris, M.; Poortmans, J. |
Title |
Spectral current-voltage analysis of kesterite solar cells |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal Of Physics D-Applied Physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
47 |
Issue |
17 |
Pages |
175101-175105 |
Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
Abstract |
Current-voltage analysis using different optical band pass filters has been performed on Cu2ZnSnSe4 and Cu2ZnSn(S, Se)(4) thin-film solar cells. When using red or orange light (i.e. wavelengths above 600 nm), a distortion appears in the I-V curve of the Cu2ZnSnSe4 solar cell, indicating an additional potential barrier to the current flow in the device for these conditions of illumination. This barrier is reduced when using a Cu2ZnSn(S, Se)(4) absorber. Numerical simulations demonstrate that the barrier visible under red light could be explained by a positive conduction band offset at the front interface coupled with compensating defects in the buffer layer. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000334504800003 |
Publication Date |
2014-04-10 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
25 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2014 IF: 2.721 |
Call Number |
UA @ lucian @ c:irua:117170 |
Serial |
3070 |
Permanent link to this record |
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Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
Title |
Tunneling-lifetime model for metal-oxide-semiconductor structures |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
8 |
Pages |
085315,1-085315,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this paper we investigate the basic physics of charge carriers (electrons) leaking out of the inversion layer of a metal-oxide-semiconductor capacitor with a biased gate. In particular, we treat the gate leakage current as resulting from two combined processes: (1) the time-dependent decay of electron wave packets representing the inversion-layer charge and (2) the local generation of new electrons replacing those that have leaked away. As a result, the gate current simply emerges as the ratio of the total charge in the inversion layer to the tunneling lifetime. The latter is extracted from the quantum dynamics of the decaying wave packets, while the generation rate is incorporated as a phenomenological source term in the continuity equation. Not only do the gate currents calculated with this model agree very well with experiment, the model also provides an onset to solve the paradox of the current-free bound states representing the resonances of the Schrödinger equation that governs the fully coupled metal-oxide-semiconductor system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000269639300076 |
Publication Date |
2009-08-21 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:78294 |
Serial |
3763 |
Permanent link to this record |
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Author |
Oueslati, S.; Brammertz, G.; Buffiere, M.; ElAnzeery, H.; Touayar, O.; Koeble, C.; Bekaert, J.; Meuris, M.; Poortmans, J. |
Title |
Physical and electrical characterization of high-performance Cu2ZnSnSe4 based thin film solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
582 |
Issue |
582 |
Pages |
224-228 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We report on the electrical, optical and physical properties of Cu2ZnSnSe4 solar cells using an absorber layer fabricated by selenization of sputtered Cu, Zn and Cu10Sn90 multilayers. A maximum active-area conversion efficiency of 10.4% under AM1.5G was measured with a maximum short circuit current density of 39.7 mA/cm(2), an open circuit voltage of 394 mV and a fill factor of 66.4%. We perform electrical and optical characterization using photoluminescence spectroscopy, external quantum efficiency, current-voltage and admittance versus temperature measurements in order to derive information about possible causes for the low open circuit voltage values observed. The main defects derived from these measurements are strong potential fluctuations in the absorber layer as well as a potential barrier of the order of 133 meV at the back side contact. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000352225900048 |
Publication Date |
2014-10-20 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0040-6090 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
49 |
Open Access |
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Notes |
; We would like to acknowledge Tom De Geyter, Greetje Godiers, and Guido Huyberechts from Flamac in Gent for sputtering of the metal layers. AGC is acknowledged for providing substrates. This research is partially funded by the Flemish government, Department Economy, Science and Innovation. ; |
Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
Call Number |
UA @ lucian @ c:irua:132504 |
Serial |
4225 |
Permanent link to this record |
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Author |
Garud, S.; Gampa, N.; Allen, T.G.; Kotipalli, R.; Flandre, D.; Batuk, M.; Hadermann, J.; Meuris, M.; Poortmans, J.; Smets, A.; Vermang, B. |
Title |
Surface passivation of CIGS solar cells using gallium oxide |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
Volume |
215 |
Issue |
7 |
Pages |
1700826 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This work proposes gallium oxide grown by plasma-enhanced atomic layer deposition, as a surface passivation material at the CdS buffer interface of Cu(In,Ga)Se-2 (CIGS) solar cells. In preliminary experiments, a metal-insulator-semiconductor (MIS) structure is used to compare aluminium oxide, gallium oxide, and hafnium oxide as passivation layers at the CIGS-CdS interface. The findings suggest that gallium oxide on CIGS may show a density of positive charges and qualitatively, the least interface trap density. Subsequent solar cell results with an estimated 0.5nm passivation layer show an substantial absolute improvement of 56mV in open-circuit voltage (V-OC), 1mAcm(-2) in short-circuit current density (J(SC)), and 2.6% in overall efficiency as compared to a reference (with the reference showing 8.5% under AM 1.5G). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000430128500015 |
Publication Date |
2018-02-27 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1862-6300 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.775 |
Times cited |
8 |
Open Access |
Not_Open_Access |
Notes |
; The work published in this paper was supported by the European Research Council (ERC) under the Union's Horizon 2020 research and innovation programme (grant agreement No 715027). The authors would also like to thank Dr. Marcel Simor (Solliance) for the CIGS layer fabrication and Prof. Johan Lauwaert (Universtiy of Ghent) for his guidance on DLTS measurements. ; |
Approved |
Most recent IF: 1.775 |
Call Number |
UA @ lucian @ c:irua:150761 |
Serial |
4981 |
Permanent link to this record |
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Author |
Vermang, B.; Brammertz, G.; Meuris, M.; Schnabel, T.; Ahlswede, E.; Choubrac, L.; Harel, S.; Cardinaud, C.; Arzel, L.; Barreau, N.; van Deelen, J.; Bolt, P.-J.; Bras, P.; Ren, Y.; Jaremalm, E.; Khelifi, S.; Yang, S.; Lauwaert, J.; Batuk, M.; Hadermann, J.; Kozina, X.; Handick, E.; Hartmann, C.; Gerlach, D.; Matsuda, A.; Ueda, S.; Chikyow, T.; Felix, R.; Zhang, Y.; Wilks, R.G.; Baer, M. |
Title |
Wide band gap kesterite absorbers for thin film solar cells: potential and challenges for their deployment in tandem devices |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Sustainable Energy & Fuels |
Abbreviated Journal |
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Volume |
3 |
Issue |
9 |
Pages |
2246-2259 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
This work reports on developments in the field of wide band gap Cu2ZnXY4 (with X = Sn, Si or Ge, and Y = S, Se) kesterite thin film solar cells. An overview on recent developments and the current understanding of wide band gap kesterite absorber layers, alternative buffer layers, and suitable transparent back contacts is presented. Cu2ZnGe(S,Se)(4) absorbers with absorber band gaps up to 1.7 eV have been successfully developed and integrated into solar cells. Combining a CdS buffer layer prepared by an optimized chemical bath deposition process with a 1.36 eV band gap absorber resulted in a record Cu2ZnGeSe4 cell efficiency of 7.6%, while the highest open-circuit voltage of 730 mV could be obtained for a 1.54 eV band gap absorber and a Zn(O,S) buffer layer. Employing InZnOx or TiO2 protective top layers on SnO2:In transparent back contacts yields 85-90% of the solar cell performance of reference cells (with Mo back contact). These advances show the potential as well as the challenges of wide band gap kesterites for future applications in high-efficiency and low-cost tandem photovoltaic devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000482057500004 |
Publication Date |
2019-06-14 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
2 |
Open Access |
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Notes |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Program under grant agreement No. 640868. The synchrotron radiation experiments were performed at the SPring-8 beamline BL15XU with the approval of the NIMS Synchrotron X-ray Station (Proposals 2016A4600, 2016B4601, and 2017A4600) and at BESSY II with the approval of HZB. B. Vermang has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (grant agreement no. 715027). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:161785 |
Serial |
5404 |
Permanent link to this record |
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Author |
Ranjbar, S.; Hadipour, A.; Vermang, B.; Batuk, M.; Hadermann, J.; Garud, S.; Sahayaraj, S.; Meuris, M.; Brammertz, G.; da Cunha, A.F.; Poortmans, J. |
Title |
P-N Junction Passivation in Kesterite Solar Cells by Use of Solution-Processed TiO2 Layer |
Type |
A1 Journal article |
Year |
2017 |
Publication |
IEEE journal of photovoltaics |
Abbreviated Journal |
Ieee J Photovolt |
Volume |
7 |
Issue |
7 |
Pages |
1130-1135 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
In this work, we used a solution-processed TiO2 layer between Cu2ZnSnSe4 and CdS buffer layer to reduce the recombination at the p–n junction. Introducing the TiO2 layer showed a positive impact on VOC but fill factor and efficiency decreased. Using a KCN treatment, we could create openings in the TiO2 layer, as confirmed by transmission electron microscopy measurements. Formation of these openings in the TiO2 layer led to the improvement of the short-circuit current, fill factor, and the efficiency of the modified solar cells. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000404258900026 |
Publication Date |
2017-04-25 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2156-3381 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.712 |
Times cited |
2 |
Open Access |
OpenAccess |
Notes |
This work was supported in part by the European Union’s Horizon 2020 research and innovation program under Grant 640868, in part by the Flemish government, Department Economy, Science and Innovation, in part by the FEDER funds through the COMPETE 2020 Programme, and in part by the National Funds through FCT – Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013. The work of S. Ranjbar was supported by the Portuguese Science and Technology Foundation through Ph.D. grant SFRH/BD/78409/2011. The work of B. Vermang was supported by the Flemish Research Foundation FWO (mandate 12O4215N). |
Approved |
Most recent IF: 3.712 |
Call Number |
EMAT @ emat @ c:irua:143986 |
Serial |
4583 |
Permanent link to this record |
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Author |
Khelifi, S.; Brammertz, G.; Choubrac, L.; Batuk, M.; Yang, S.; Meuris, M.; Barreau, N.; Hadermann, J.; Vrielinck, H.; Poelman, D.; Neyts, K.; Vermang, B.; Lauwaert, J. |
Title |
The path towards efficient wide band gap thin-film kesterite solar cells with transparent back contact for viable tandem application |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Solar Energy Materials And Solar Cells |
Abbreviated Journal |
Sol Energ Mat Sol C |
Volume |
219 |
Issue |
|
Pages |
110824 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Wide band gap thin-film kesterite solar cell based on non-toxic and earth-abundant materials might be a suitable candidate as a top cell for tandem configuration in combination with crystalline silicon as a bottom solar cell. For this purpose and based on parameters we have extracted from electrical and optical characterization techniques of Cu2ZnGeSe4 absorbers and solar cells, a model has been developed to describe the kesterite top cell efficiency limitations and to investigate the different possible configurations with transparent back contact for fourterminal tandem solar cell application. Furthermore, we have studied the tandem solar cell performance in view of the band gap and the transparency of the kesterite top cell and back contact engineering. Our detailed analysis shows that a kesterite top cell with efficiency > 14%, a band gap in the range of 1.5-1.7 eV and transparency above 80% at the sub-band gaps photons energies are required to achieve a tandem cell with higher efficiency than with a single silicon solar cell. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000591683500002 |
Publication Date |
2020-10-08 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0927-0248 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.784 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
The authors would like to acknowledge the SWInG project financed by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 640868 and the Research Foundation Flanders-Hercules Foundation (FWO-Vlaanderen, project No AUGE/13/16:FT-IMAGER). |
Approved |
Most recent IF: 4.784 |
Call Number |
EMAT @ emat @c:irua:174337 |
Serial |
6706 |
Permanent link to this record |