Records |
Author |
Clima, S.; Belmonte, A.; Degraeve, R.; Fantini, A.; Goux, L.; Govoreanu, B.; Jurczak, M.; Ota, K.; Redolfi, A.; Kar, G.S.; Pourtois, G. |
Title |
Kinetic and thermodynamic heterogeneity : an intrinsic source of variability in Cu-based RRAM memories |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
Volume |
16 |
Issue |
4 |
Pages |
1011-1016 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('The resistive random-access memory (RRAM) device concept is close to enabling the development of a new generation of non-volatile memories, provided that their reliability issues are properly understood. The design of a RRAM operating with extrinsic defects based on metallic inclusions, also called conductive bridge RAM, allows the use of a large spectrum of solid electrolytes. However, when scaled to device dimensions that meet the requirements of the latest technological nodes, the discrete nature of the atomic structure of the materials impacts the device operation. Using density functional theory simulations, we evaluated the migration kinetics of Cu conducting species in amorphous and solid electrolyte materials, and established that atomic disorder leads to a large variability in terms of defect stability and kinetic barriers. This variability has a significant impact on the filament resistance and its dynamics, as evidenced during the formation step of the resistive filament. Also, the atomic configuration of the formed filament can age/relax to another metastable atomic configuration, and lead to a modulation of the resistivity of the filament. All these observations are qualitatively explained on the basis of the computed statistical distributions of the defect stability and on the kinetic barriers encountered in RRAM materials.')); |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Place of publication unknown |
Editor |
|
Language |
|
Wos |
000417598100004 |
Publication Date |
2017-08-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1569-8025 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.526 |
Times cited |
2 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 1.526 |
Call Number |
UA @ lucian @ c:irua:148569 |
Serial |
4883 |
Permanent link to this record |
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|
Author |
Sorée, B.; Magnus, W.; Pourtois, G. |
Title |
Analytical and self-consistent quantum mechanical model for a surrounding gate MOS nanowire operated in JFET mode |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
Volume |
7 |
Issue |
3 |
Pages |
380-383 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We derive an analytical model for the electrostatics and the drive current in a silicon nanowire operating in JFET mode. We show that there exists a range of nanowire radii and doping densities for which the nanowire JFET satisfies reasonable device characteristics. For thin nanowires we have developed a self-consistent quantum mechanical model to obtain the electronic structure. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
000208473800067 |
Publication Date |
2008-02-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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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 |
70 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.526; 2008 IF: NA |
Call Number |
UA @ lucian @ c:irua:89504 |
Serial |
107 |
Permanent link to this record |
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|
Author |
Phung, Q.M.; Vancoillie, S.; Delabie, A.; Pourtois, G.; Pierloot, K. |
Title |
Ruthenocene and cyclopentadienyl pyrrolyl ruthenium as precursors for ruthenium atomic layer deposition : a comparative study of dissociation enthalpies |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Theoretical chemistry accounts : theory, computation, and modeling |
Abbreviated Journal |
Theor Chem Acc |
Volume |
131 |
Issue |
7 |
Pages |
1238 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
RuCp2 (ruthenocene) and RuCpPy (cyclopentadienyl pyrrolyl ruthenium) complexes are used in ruthenium (Ru) atomic layer deposition (ALD) but exhibit a markedly different reactivity with respect to the substrate and co-reactant. In search of an explanation, we report here the results of a comparative study of the heterolytic and homolytic dissociation enthalpy of these two ruthenium complexes, making use of either density functional theory (DFT) or multiconfigurational perturbation theory (CASPT2). While both methods predict distinctly different absolute dissociation enthalpies, they agree on the relative values between both molecules. A reduced heterolytic dissociation enthalpy is obtained for RuCpPy compared to RuCp2, although the difference obtained from CASPT2 (19.9 kcal/mol) is slightly larger than the one obtained with any of the DFT functionals (around 17 kcal/mol). Both methods also agree on the more pronounced stability of the Cp- ligand in RuCpPy than in RuCp2 (by around 9 kcal/mol with DFT and by 6 kcal/mol with CASPT2). |
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 |
000307274300003 |
Publication Date |
2012-07-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1432-881X;1432-2234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.89 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.89; 2012 IF: 2.233 |
Call Number |
UA @ lucian @ c:irua:101139 |
Serial |
2935 |
Permanent link to this record |
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|
Author |
Clima, S.; Garbin, D.; Opsomer, K.; Avasarala, N.S.; Devulder, W.; Shlyakhov, I.; Keukelier, J.; Donadio, G.L.; Witters, T.; Kundu, S.; Govoreanu, B.; Goux, L.; Detavernier, C.; Afanas'ev, V.; Kar, G.S.; Pourtois, G. |
Title |
Ovonic threshold-switching GexSey chalcogenide materials : stoichiometry, trap nature, and material relaxation from first principles |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physica Status Solidi-Rapid Research Letters |
Abbreviated Journal |
Phys Status Solidi-R |
Volume |
|
Issue |
|
Pages |
1900672 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Density functional theory simulations are used to identify the structural factors that define the material properties of ovonic threshold switches (OTS). They show that the nature of mobility-gap trap states in amorphous Ge-rich Ge50Se50 is related to Ge-Ge bonds, whereas in Se-rich Ge30Se70 the Ge valence-alternating-pairs and Se lone-pairs dominate. To obtain a faithful description of the electronic structure and delocalization of states, it is required to combine hybrid exchange-correlation functionals with large unit-cell models. The extent of localization of electronic states depends on the applied external electric field. Hence, OTS materials undergo structural changes during electrical cycling of the device, with a decrease in the population of less exothermic Ge-Ge bonds in favor of more exothermic Ge-Se. This reduces the amount of charge traps, which translates into coordination changes, an increase in mobility-gap, and subsequently changes in the selector-device electrical parameters. The threshold voltage drift process can be explained by natural evolution of the nonpreferred Ge-Ge bonds (or “chains”/clusters thereof) in Ge-rich GexSe1-x. The effect of extrinsic doping is shown for Si and N, which introduce strong covalent bonds into the system, increase both mobility-gap and crystallization temperature, and decrease the leakage current. |
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 |
|
Wos |
000512431100001 |
Publication Date |
2020-01-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1862-6254 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.8 |
Times cited |
3 |
Open Access |
|
Notes |
; This work was carried out in the framework of the imec Core CMOS-Emerging Memory Program. Financial support from EU H2020-NMBPTO-IND-2018 project “INTERSECT” (Grant No. 814487) is acknowledged. ; |
Approved |
Most recent IF: 2.8; 2020 IF: 3.032 |
Call Number |
UA @ admin @ c:irua:166492 |
Serial |
6575 |
Permanent link to this record |
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|
|
Author |
Clima, S.; Sankaran, K.; Chen, Y.Y.; Fantini, A.; Celano, U.; Belmonte, A.; Zhang, L.; Goux, L.; Govoreanu, B.; Degraeve, R.; Wouters, D.J.; Jurczak, M.; Vandervorst, W.; Gendt, S.D.; Pourtois, G.; |
Title |
RRAMs based on anionic and cationic switching : a short overview |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physica status solidi: rapid research letters |
Abbreviated Journal |
Phys Status Solidi-R |
Volume |
8 |
Issue |
6 |
Pages |
501-511 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Resistive random access memories are emerging as a new type of memory that has the potential to combine both the speed of volatile and the retention of nonvolatile memories. It operates based on the formation/dissolution of a low-resistivity filament being constituted of either metallic ions or atomic vacancies within an insulating matrix. At present, the mechanisms and the parameters controlling the performances of the device remain unclear. In that respect, first-principles simulations provide useful insights on the atomistic mechanisms, the thermodynamic and kinetics factors that modulate the material conductivity, providing guidance into the engineering of the operation of the device. In this paper, we review the current state-of-the-art knowledge on the atomistic switching mechanisms driving the operation of copper-based conductive bridge RRAM and HfOx valence change RRAM. [GRAPHICS] Conceptual illustration of the RRAM device with the filament formation and disruption during its operation. AE/IM/CE are the active electrode/insulating matrix/counterelectrode. The blue circles represent the conducting defects. (C) 2014 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000338021200004 |
Publication Date |
2014-04-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1862-6254; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.032 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.032; 2014 IF: 2.142 |
Call Number |
UA @ lucian @ c:irua:118679 |
Serial |
2933 |
Permanent link to this record |
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|
|
Author |
van den Broek, B.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
Title |
Current-voltage characteristics of armchair Sn nanoribbons |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physica status solidi: rapid research letters |
Abbreviated Journal |
Phys Status Solidi-R |
Volume |
8 |
Issue |
11 |
Pages |
931-934 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Two-dimensional group-IV lattices silicene and germanene are known to share many of graphene's remarkable mechanical and electronic properties. Due to the out-of-plane buckling of the former materials, there are more means of electronic funtionalization, e.g. by applying uniaxial strain or an out-of-plane electric field. We consider monolayer hexagonal Sn (stanene) as an ideal candidate to feasibly implement and exploit graphene physics for nanoelectronic applications: with increased out-of-plane buckling and sizable spin-orbit coupling it lends itself to improved Dirac cone engineering. We investigate the ballistic charge transport regime of armchair Sn nanoribbons, classified according to the ribbon width W = {3m – 1, 3m, 3m + 1} with integer m. We study transport through (non-magnetic) armchair ribbons using a combination of density functional theory and non-equilibrium Green's functions. Sn ribbons have earlier current onsets and carry currents 20% larger than C/Si/Ge-nanoribbons as the contact resistance of these ribbons is found to be comparable. ((c) 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000345274300009 |
Publication Date |
2014-09-25 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1862-6254; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.032 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.032; 2014 IF: 2.142 |
Call Number |
UA @ lucian @ c:irua:122148 |
Serial |
594 |
Permanent link to this record |
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|
Author |
de de Meux, A.J.; Bhoolokam, A.; Pourtois, G.; Genoe, J.; Heremans, P. |
Title |
Oxygen vacancies effects in a-IGZO : formation mechanisms, hysteresis, and negative bias stress effects |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
Volume |
214 |
Issue |
6 |
Pages |
1600889 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The amorphous oxide semiconductor Indium-Gallium-Zinc-Oxide (a-IGZO) has gained a large technological relevance as a semiconductor for thin-film transistors in active-matrix displays. Yet, major questions remain unanswered regarding the atomic origin of threshold voltage control, doping level, hysteresis, negative bias stress (NBS), and negative bias illumination stress (NBIS). We undertake a systematic study of the effects of oxygen vacancies on the properties of a-IGZO by relating experimental observations to microscopic insights gained from first-principle simulations. It is found that the amorphous nature of the semiconductor allows unusually large atomic relaxations. In some cases, oxygen vacancies are found to behave as perfect shallow donors without the formation of structural defects. Once structural defects are formed, their transition states can vary upon charge and discharge cycles. We associate this phenomenon to a possible presence of hysteresis in the transfer curve of the devices. Under NBS, the creation of oxygen vacancies becomes energetically very stable, hence thermodynamically very likely. This generation process is correlated with the occurrence of the negative bias stress instabilities observed in a-IGZO transistors. While oxygen vacancies can therefore be related to NBS and hysteresis, it appears unlikely from our results that they are direct causes of NBIS, contrary to common belief. |
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 |
|
Wos |
000403339900012 |
Publication Date |
2017-03-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1862-6300 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.775 |
Times cited |
8 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 1.775 |
Call Number |
UA @ lucian @ c:irua:144219 |
Serial |
4678 |
Permanent link to this record |
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|
Author |
Cornil, D.; Li, H.; Wood, C.; Pourtois, G.; Bredas, J.-L.; Cornil, J. |
Title |
Work-function modification of Au and Ag surfaces upon deposition of self-assembled monolayers : influence of the choice of the theoretical approach and the thiol decomposition scheme |
Type |
A1 Journal article |
Year |
2013 |
Publication |
ChemPhysChem : a European journal of chemical physics and physical chemistry |
Abbreviated Journal |
Chemphyschem |
Volume |
14 |
Issue |
13 |
Pages |
2939-2946 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We have characterized theoretically the work-function modifications of the (111) surfaces of gold and silver upon deposition of self-assembled monolayers based on methanethiol and trifluoromethanethiol. A comparative analysis is made between the experimental results and those obtained from two widely used approaches based on density functional theory. The contributions to the total work-function modifications are estimated on the basis of two decomposition schemes of the thiol molecules that have been proposed in the literature. The contributions are found to differ significantly between the two approaches, as do the corresponding adsorption energies. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000324316000014 |
Publication Date |
2013-07-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1439-4235; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.075 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.075; 2013 IF: 3.360 |
Call Number |
UA @ lucian @ c:irua:112278 |
Serial |
3923 |
Permanent link to this record |
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Author |
Adelmann, C.; Wen, L.G.; Peter, A.P.; Pourtois, G.; et al. |
Title |
Alternative metals for advanced interconnects |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
2014 Ieee International Interconnect Technology Conference / Advanced Metallization Conference (iitc/amc) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
173-175 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We discuss the selection criteria for alternative metals in order to fulfill the requirements necessary for interconnects at half pitch values below 10 nm. The performance of scaled interconnects using transition metal germanides and CoAl alloys as metallization are studied and compared to conventional Cu and W interconnects. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-4799-5018-8 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:127033 |
Serial |
91 |
Permanent link to this record |
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Author |
Sankaran, K.; Clima, S.; Mees, M.; Adelmann, C.; Tokei, Z.; Pourtois, G. |
Title |
Exploring alternative metals to Cu and W for interconnects : an ab initio Insight |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
2014 Ieee International Interconnect Technology Conference / Advanced Metallization Conference (iitc/amc) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
193-195 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The properties of alternative metals to Cu and W for interconnect applications are reviewed based on first-principles simulations and benchmarked in terms of intrinsic bulk resistivity and electromigration. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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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 |
|
Edition |
|
ISSN |
978-1-4799-5018-8 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:127034 |
Serial |
1149 |
Permanent link to this record |
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|
|
Author |
Sorée, B.; Magnus, W.; Szepieniec, M.; Vandenbreghe, W.; Verhulst, A.; Pourtois, G.; Groeseneken, G.; de Gendt, S.; Heyns, M. |
Title |
Novel device concepts for nanotechnology : the nanowire pinch-off FET and graphene tunnelFET |
Type |
A2 Journal article |
Year |
2010 |
Publication |
ECS transactions |
Abbreviated Journal |
|
Volume |
28 |
Issue |
|
Pages |
15-26 |
Keywords |
A2 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We explain the basic operation of a nanowire pinch-off FET and graphene nanoribbon tunnelFET. For the nanowire pinch-off FET we construct an analytical model to obtain the threshold voltage as a function of radius and doping density. We use the gradual channel approximation to calculate the current-voltage characteristics of this device and we show that the nanowire pinch-off FET has a subthreshold slope of 60 mV/dec and good ION and ION/IOFF ratios. For the graphene nanoribbon tunnelFET we show that an improved analytical model yields more realistic results for the transmission probability and hence the tunneling current. The first simulation results for the graphene nanoribbon tunnelFET show promising subthreshold slopes. |
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 |
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Publication Date |
0000-00-00 |
Series Editor |
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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 |
|
Edition |
|
ISSN |
1938-5862 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:89510 |
Serial |
2375 |
Permanent link to this record |
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|
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Author |
Sankaran, K.; Swerts, J.; Carpenter, R.; Couet, S.; Garello, K.; Evans, R.F.L.; Rao, S.; Kim, W.; Kundu, S.; Crotti, D.; Kar, G.S.; Pourtois, G. |
Title |
Evidence of magnetostrictive effects on STT-MRAM performance by atomistic and spin modeling |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 Ieee International Electron Devices Meeting (iedm) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
For the first time, we demonstrate, using an atomistic description of a 30nm diameter spin-transfer-torque magnetic random access memories (STT-MRAM), that the difference in mechanical properties of its sub-nanometer layers induces a high compressive strain in the magnetic tunnel junction (MTJ) and leads to a detrimental magnetostrictive effect. Our model explains the issues met in engineering the electrical and magnetic performances in scaled STT-MRAM devices. The resulting high compressive strain built in the stack, particularly in the MgO tunnel barrier (t-MgO), and its associated non-uniform atomic displacements, impacts on the quality of the MTJ interface and leads to strain relieve mechanisms such as surface roughness and adhesion issues. We illustrate that the strain gradient induced by the different materials and their thicknesses in the stacks has a negative impact on the tunnel magneto-resistance (TMR), on the magnetic nucleation process and on the STT-MRAM performance. |
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 |
000459882300147 |
Publication Date |
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Series Editor |
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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 |
|
Edition |
|
ISSN |
978-1-72811-987-8; 978-1-72811-987-8 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:158694 |
Serial |
7942 |
Permanent link to this record |
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Author |
Clima, S.; McMitchell, S.R.C.; Florent, K.; Nyns, L.; Popovici, M.; Ronchi, N.; Di Piazza, L.; Van Houdt, J.; Pourtois, G. |
Title |
First-principles perspective on poling mechanisms and ferroelectric/antiferroelectric behavior of Hf1-xZrxO2 for FEFET applications |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 Ieee International Electron Devices Meeting (iedm) |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
|
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We investigate at the atomic level the most probable phase transformations under strain, that are responsible for the ferroelectric/ antiferroelectric behavior in Hf1-xZrxO2 materials. Four different crystalline phase transformations exhibit a polar/non-polar transition: monoclinic-to-orthorhombic requires a gliding strain tensor, orthorhombic-to-orthorhombic transformation does not need strain to polarize the material, whereas tetragonal-to-cubic cell compression and tetragonal-to-orthorhombic cell elongation destabilizes the non-polar tetragonal phase, facilitating the transition towards a polar atomic configuration, therefore changing the polarization-electric field loop from antiferroelectric to ferroelectric. Oxygen vacancies can reduce drastically the polarization reversal barriers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000459882300073 |
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-72811-987-8; 978-1-72811-987-8 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:158693 |
Serial |
7972 |
Permanent link to this record |
|
|
|
Author |
Sankaran, K.; Moors, K.; Dutta, S.; Adelmann, C.; Tokei, Z.; Pourtois, G. |
Title |
Metallic ceramics for low resitivity interconnects : an ab initio insight |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
Proceedings of the IEEE ... International Interconnect Technology Conference
T2 – IEEE International Interconnect Technology Conference (IITC), JUN 04-07, 2018, Santa Clara, CA |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
160-162 |
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The scalability potential of low resistivity ternary metallic alloys (MAX) as an interconnect medium has been benchmarked against copper through first-principle simulations. We report that some carbon and nitrogen MAX phases have the potential to display a reduced sensitivity of their intrinsic resistivity to scaling, while showing improved electromigration properties. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000468672900053 |
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-5386-4337-2; 978-1-5386-4337-2 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:160474 |
Serial |
8219 |
Permanent link to this record |
|
|
|
Author |
Yu, H.; Schaekers, M.; Chew, S.A.; Eyeraert, J.-L.; Dabral, A.; Pourtois, G.; Horiguchi, N.; Mocuta, D.; Collaert, N.; De Meyer, K. |
Title |
Titanium (germano-)silicides featuring 10-9 Ω.cm2 contact resistivity and improved compatibility to advanced CMOS technology |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 18th International Workshop On Junction Technology (iwjt) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
80-84
T2 - 18th International Workshop on Junction |
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
uIn this work, we discuss three novel Ti (germano-)silicidation techniques featuring respectively the pre-contact amorphization implantation (PCAI), the TiSi co-deposition, and Ti atomic layer deposition (ALD). All three techniques form TiSix(Ge-y) contacts with ultralow contact resistivity (rho(c)) of (1-3)x10(-9) Omega.cm(2) on both highly doped n-Si and p-SiGe substrates: these techniques meet rho(c) requirement of 5-14 nm CMOS technology and feature unified CMOS contact solutions. We further discuss the compatibility of these techniques to the realistic CMOS transistor fabrication. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000502768600020 |
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-5386-4511-6; 978-1-5386-4511-6 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:165190 |
Serial |
8673 |
Permanent link to this record |
|
|
|
Author |
van den Broek, B.; Houssa, M.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
Title |
Two-dimensional hexagonal tin : ab initio geometry, stability, electronic structure and functionalization |
Type |
A1 Journal article |
Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
1 |
Issue |
|
Pages |
021004 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We study the structural, mechanical and electronic properties of the two-dimensional (2D) allotrope of tin: tinene/stanene using first-principles calculation within density functional theory, implemented in a set of computer codes. Continuing the trend of the group-IV 2D materials graphene, silicene and germanene; tinene is predicted to have a honeycomb lattice with lattice parameter of a(0) = 4.62 angstrom and a buckling of d(0) = 0.92 angstrom. The electronic dispersion shows a Dirac cone with zero gap at the Fermi energy and a Fermi velocity of v(F) = 0.97 x 10(6) m s(-1); including spin-orbit coupling yields a bandgap of 0.10 eV. The monolayer is thermally stable up to 700 K, as indicated by first-principles molecular dynamics, and has a phonon dispersion without imaginary frequencies. We explore applied electric field and applied strain as functionalization mechanisms. Combining these two mechanisms allows for an induced bandgap up to 0.21 eV, whilst retaining the linear dispersion, albeit with degraded electronic transport parameters. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000353650400004 |
Publication Date |
2014-08-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
58 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
Call Number |
UA @ lucian @ c:irua:134432 |
Serial |
4530 |
Permanent link to this record |
|
|
|
Author |
Scalise, E.; Houssa, M.; Cinquanta, E.; Grazianetti, C.; van den Broek, B.; Pourtois, G.; Stesmans, A.; Fanciulli, M.; Molle, A. |
Title |
Engineering the electronic properties of silicene by tuning the composition of MoX2 and GaX (X = S,Se,Te) chalchogenide templates |
Type |
A1 Journal article |
Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
1 |
Issue |
1 |
Pages |
011010 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
By using first-principles simulations, we investigate the interaction of a 2D silicon layer with two classes of chalcogenide-layered compounds, namely MoX2 and GaX (X = S, Se, Te). A rather weak (van der Waals) interaction between the silicene layers and the chalcogenide layers is predicted. We found that the buckling of the silicene layer is correlated to the lattice mismatch between the silicene layer and the MoX2 or GaX template. The electronic properties of silicene on these different templates largely depend on the buckling of the silicene layer: highly buckled silicene on MoS2 is predicted to be metallic, while low buckled silicene on GaS and GaSe is predicted to be semi-metallic, with preserved Dirac cones at the K points. These results indicate new routes for artificially engineering silicene nanosheets, providing tailored electronic properties of this 2D layer on non-metallic substrates. These non-metallic templates also open the way to the possible integration of silicene in future nanoelectronic devices. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000353649900011 |
Publication Date |
2014-05-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
49 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
Call Number |
UA @ lucian @ c:irua:126032 |
Serial |
1048 |
Permanent link to this record |
|
|
|
Author |
Schoeters, B.; Neyts, E.C.; Khalilov, U.; Pourtois, G.; Partoens, B. |
Title |
Stability of Si epoxide defects in Si nanowires : a mixed reactive force field/DFT study |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
15 |
Issue |
36 |
Pages |
15091-15097 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Modeling the oxidation process of silicon nanowires through reactive force field based molecular dynamics simulations suggests that the formation of Si epoxide defects occurs both at the Si/SiOx interface and at the nanowire surface, whereas for flat surfaces, this defect is experimentally observed to occur only at the interface as a result of stress. In this paper, we argue that the increasing curvature stabilizes the defect at the nanowire surface, as suggested by our density functional theory calculations. The latter can have important consequences for the opto-electronic properties of thin silicon nanowires, since the epoxide induces an electronic state within the band gap. Removing the epoxide defect by hydrogenation is expected to be possible but becomes increasingly difficult with a reduction of the diameter of the nanowires. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000323520600029 |
Publication Date |
2013-07-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
3 |
Open Access |
|
Notes |
; BS gratefully acknowledges financial support of the IWT, Institute for the Promotion of Innovation by Science and Technology in Flanders, via the SBO project “SilaSol”. This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. ; |
Approved |
Most recent IF: 4.123; 2013 IF: 4.198 |
Call Number |
UA @ lucian @ c:irua:110793 |
Serial |
3130 |
Permanent link to this record |
|
|
|
Author |
Schoeters, B.; Leenaerts, O.; Pourtois, G.; Partoens, B. |
Title |
Ab-initio study of the segregation and electronic properties of neutral and charged B and P dopants in Si and Si/SiO2 nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
104306 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We perform first-principles calculations to investigate the preferred positions of B and P dopants, both neutral and in their preferred charge state, in Si and Si/SiO2 core-shell nanowires (NWs). In order to understand the observed trends in the formation energy, we isolate the different effects that determine these formation energies. By making the distinction between the unrelaxed and the relaxed formation energy, we separate the impact of the relaxation from that of the chemical environment. The unrelaxed formation energies are determined by three effects: (i) the effect of strain caused by size mismatch between the dopant and the host atoms, (ii) the local position of the band edges, and (iii) a screening effect. In the case of the SiNW (Si/SiO2 NW), these effects result in an increase of the formation energy away from the center (interface). The effect of relaxation depends on the relative size mismatch between the dopant and host atoms. A large size mismatch causes substantial relaxation that reduces the formation energy considerably, with the relaxation being more pronounced towards the edge of the wires. These effects explain the surface segregation of the B dopants in a SiNW, since the atomic relaxation induces a continuous drop of the formation energy towards the edge. However, for the P dopants, the formation energy starts to rise when moving from the center but drops to a minimum just next to the surface, indicating a different type of behavior. It also explains that the preferential location for B dopants in Si/SiO2 core-shell NWs is inside the oxide shell just next to the interface, whereas the P dopants prefer the positions next to the interface inside the Si core, which is in agreement with recent experiments. These preferred locations have an important impact on the electronic properties of these core-shell NWs. Our simulations indicate the possibility of hole gas formation when B segregates into the oxide shell. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000361636900031 |
Publication Date |
2015-09-09 |
Series Editor |
|
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 |
This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:128729 |
Serial |
4056 |
Permanent link to this record |
|
|
|
Author |
Dhayalan, S.K.; Kujala, J.; Slotte, J.; Pourtois, G.; Simoen, E.; Rosseel, E.; Hikavyy, A.; Shimura, Y.; Iacovo, S.; Stesmans, A.; Loo, R.; Vandervorst, W.; |
Title |
On the manifestation of phosphorus-vacancy complexes in epitaxial Si:P films |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
108 |
Issue |
108 |
Pages |
082106 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In situ doped epitaxial Si: P films with P concentrations > 1 x 10(21) at./cm(3) are suitable for source-drain stressors of n-FinFETs. These films combine the advantages of high conductivity derived from the high P doping with the creation of tensile strain in the Si channel. It has been suggested that the tensile strain developed in the Si: P films is due to the presence of local Si3P4 clusters, which however do not contribute to the electrical conductivity. During laser annealing, the Si3P4 clusters are expected to disperse resulting in an increased conductivity while the strain reduces slightly. However, the existence of Si3P4 is not proven. Based on first-principles simulations, we demonstrate that the formation of vacancy centered Si3P4 clusters, in the form of four P atoms bonded to a Si vacancy, is thermodynamically favorable at such high P concentrations. We suggest that during post epi-growth annealing, a fraction of the P atoms from these clusters are activated, while the remaining part goes into interstitial sites, thereby reducing strain. We corroborate our conjecture experimentally using positron annihilation spectroscopy, electron spin resonance, and Rutherford backscattering ion channeling studies. (C) 2016 AIP Publishing LLC. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000373057000023 |
Publication Date |
2016-02-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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 |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.411 |
Call Number |
UA @ lucian @ c:irua:133245 |
Serial |
4217 |
Permanent link to this record |
|
|
|
Author |
Clima, S.; Chen, Y.Y.; Chen, C.Y.; Goux, L.; Govoreanu, B.; Degraeve, R.; Fantini, A.; Jurczak, M.; Pourtois, G. |
Title |
First-principles thermodynamics and defect kinetics guidelines for engineering a tailored RRAM device |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
119 |
Issue |
119 |
Pages |
225107 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Resistive Random Access Memories are among the most promising candidates for the next generation of non-volatile memory. Transition metal oxides such as HfOx and TaOx attracted a lot of attention due to their CMOS compatibility. Furthermore, these materials do not require the inclusion of extrinsic conducting defects since their operation is based on intrinsic ones (oxygen vacancies). Using Density Functional Theory, we evaluated the thermodynamics of the defects formation and the kinetics of diffusion of the conducting species active in transition metal oxide RRAM materials. The gained insights based on the thermodynamics in the Top Electrode, Insulating Matrix and Bottom Electrode and at the interfaces are used to design a proper defect reservoir, which is needed for a low-energy reliable switching device. The defect reservoir has also a direct impact on the retention of the Low Resistance State due to the resulting thermodynamic driving forces. The kinetics of the diffusing conducting defects in the Insulating Matrix determine the switching dynamics and resistance retention. The interface at the Bottom Electrode has a significant impact on the low-current operation and long endurance of the memory cell. Our first-principles findings are confirmed by experimental measurements on fabricated RRAM devices. Published by AIP Publishing. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000378925400035 |
Publication Date |
2016-06-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ lucian @ c:irua:134651 |
Serial |
4181 |
Permanent link to this record |
|
|
|
Author |
Lu, A.K.A.; Pourtois, G.; Luisier, M.; Radu, I.P.; Houssa, M. |
Title |
On the electrostatic control achieved in transistors based on multilayered MoS2 : a first-principles study |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of applied physics |
Abbreviated Journal |
|
Volume |
121 |
Issue |
4 |
Pages |
044505 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this work, the electrostatic control in metal-oxide-semiconductor field-effect transistors based on MoS2 is studied, with respect to the number of MoS2 layers in the channel and to the equivalent oxide thickness of the gate dielectric, using first-principles calculations combined with a quantum transport formalism. Our simulations show that a compromise exists between the drive current and the electrostatic control on the channel. When increasing the number of MoS2 layers, a degradation of the device performances in terms of subthreshold swing and OFF currents arises due to the screening of the MoS2 layers constituting the transistor channel. Published by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000393480100030 |
Publication Date |
2017-01-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:152673 |
Serial |
8329 |
Permanent link to this record |
|
|
|
Author |
de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. |
Title |
Effects of hole self-trapping by polarons on transport and negative bias illumination stress in amorphous-IGZO |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
123 |
Issue |
16 |
Pages |
161513 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The effects of hole injection in amorphous indium-gallium-zinc-oxide (a-IGZO) are analyzed by means of first-principles calculations. The injection of holes in the valence band tail states leads to their capture as a polaron, with high self-trapping energies (from 0.44 to 1.15 eV). Once formed, they mediate the formation of peroxides and remain localized close to the hole injection source due to the presence of a large diffusion energy barrier (of at least 0.6 eV). Their diffusion mechanism can be mediated by the presence of hydrogen. The capture of these holes is correlated with the low off-current observed for a-IGZO transistors, as well as with the difficulty to obtain a p-type conductivity. The results further support the formation of peroxides as being the root cause of Negative Bias Illumination Stress (NBIS). The strong self-trapping substantially reduces the injection of holes from the contact and limits the creation of peroxides from a direct hole injection. In the presence of light, the concentration of holes substantially rises and mediates the creation of peroxides, responsible for NBIS. Published by AIP Publishing. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Amer inst physics |
Place of Publication |
Melville |
Editor |
|
Language |
|
Wos |
000431147200043 |
Publication Date |
2017-10-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ lucian @ c:irua:151570 |
Serial |
5021 |
Permanent link to this record |
|
|
|
Author |
Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Porret, C.; Loo, R.; Vandervorst, W. |
Title |
Heavily phosphorus doped germanium : strong interaction of phosphorus with vacancies and impact of tin alloying on doping activation |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
125 |
Issue |
22 |
Pages |
225703 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We examined the vacancy trapping proficiency of Sn and P atoms in germanium using positron annihilation spectroscopy measurements, sensitive to the open-volume defects. Epitaxial Ge1 xSnx films were grown by chemical vapor deposition with different P concentrations in the 3: 0 1019-1: 5 1020 cm 3 range. We corroborate our findings with first principles simulations. Codoping of Ge with a Sn concentration of up to 9% is not an efficient method to suppress the free vacancy concentration and the formation of larger phosphorus-vacancy complexes. Experimental results confirm an increase in the number of P atoms around the monovacancy with P-doping, leading to dopant deactivation in epitaxial germanium-tin layers with similar Sn content. Vice versa, no impact on the improvement of maximum achieved P activation in Ge with increasing Sn-doping has been observed. Theoretical calculations also confirm that Pn-V (vacancy) complexes are energetically more stable than the corresponding SnmPn-V and Snm-V defect structures with the same number of alien atoms (Sn or P) around the monovacancy. he strong attraction of vacancies to the phosphorus atoms remains the dominant dopant deactivation mechanism in Ge as well as in Ge1 xSnx. Published under license by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000471698600044 |
Publication Date |
2019-06-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ admin @ c:irua:161333 |
Serial |
6300 |
Permanent link to this record |
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Author |
Khanam, A.; Vohra, A.; Slotte, J.; Makkonen, I.; Loo, R.; Pourtois, G.; Vandervorst, W. |
Title |
A demonstration of donor passivation through direct formation of V-As-i complexes in As-doped Ge1-XSnx |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
Volume |
127 |
Issue |
19 |
Pages |
195703 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Positron annihilation spectroscopy in the Doppler and coincidence Doppler mode was applied on Ge1 xSnx epitaxial layers, grown by chemical vapor deposition with different total As concentrations (1019-1021 cm3), high active As concentrations (1019 cm3), and similar Sn concentrations (5.9%-6.4%). Positron traps are identified as mono-vacancy complexes. Vacancy-As complexes, V-Asi, formed during the growth were studied to deepen the understanding of the electrical passivation of the Ge1 xSnx:As epilayers. Larger monovacancy complexes, V-Asi (i 2), are formed as the As doping increases. The total As concentration shows a significant impact on the saturation of the number of As atoms (i 1/4 4) around the vacancies in the sample epilayers. The presence of V-Asi complexes decreases the dopant activation in the Ge1 xSnx:As epilayers. Furthermore, the presence of Sn failed to hinder the formation of larger V-Asi complexes and thus failed to reduce the donor-deactivation. |
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 |
000536196000003 |
Publication Date |
2020-05-15 |
Series Editor |
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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 |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.2 |
Times cited |
|
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.2; 2020 IF: 2.068 |
Call Number |
UA @ admin @ c:irua:170252 |
Serial |
6447 |
Permanent link to this record |
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Author |
Lu, A.K.A.; Houssa, M.; Luisier, M.; Pourtois, G. |
Title |
Impact of layer alignment on the behavior of MoS2-ZrS2 tunnel field-effect transistors : an ab initio study |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physical review applied |
Abbreviated Journal |
Phys Rev Appl |
Volume |
8 |
Issue |
3 |
Pages |
034017 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Tunnel field-effect transistors based on van der Waals heterostructures are emerging device concepts for low-power applications, auguring sub-60 mV/dec subthreshold swing values. In these devices, the channel is built from a stack of several different two-dimensional materials whose nature allows tailoring the band alignments and enables a good electrostatic control of the device. In this work, we propose a theoretical study of the variability of the performances of a MoS2-ZrS2 tunnel field-effect transistor induced by fluctuations of the relative position or the orientation of the layers. Our results indicate that although a steep subthreshold slope (20 mV/dec) is achievable, fluctuations in the relative orientation of the ZrS2 layer with respect to the MoS2 one lead to a significant variability in the tunneling current by about one decade. This arises from changes in the orbital overlap between the layers and from the modulation of the transport direction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000411460400001 |
Publication Date |
2017-09-22 |
Series Editor |
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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 |
2331-7019 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.808 |
Times cited |
6 |
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 4.808 |
Call Number |
UA @ lucian @ c:irua:146741 |
Serial |
4785 |
Permanent link to this record |
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Author |
de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. |
Title |
Defects in amorphous semiconductors : the case of amorphous indium gallium zinc oxide |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review applied |
Abbreviated Journal |
Phys Rev Appl |
Volume |
9 |
Issue |
9 |
Pages |
054039 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Based on a rational classification of defects in amorphous materials, we propose a simplified model to describe intrinsic defects and hydrogen impurities in amorphous indium gallium zinc oxide (a-IGZO). The proposed approach consists of organizing defects into two categories: point defects, generating structural anomalies such as metal-metal or oxygen-oxygen bonds, and defects emerging from changes in the material stoichiometry, such as vacancies and interstitial atoms. Based on first-principles simulations, it is argued that the defects originating from the second group always act as perfect donors or perfect acceptors. This classification simplifies and rationalizes the nature of defects in amorphous phases. In a-IGZO, the most important point defects are metal-metal bonds (or small metal clusters) and peroxides (O-O single bonds). Electrons are captured by metal-metal bonds and released by the formation of peroxides. The presence of hydrogen can lead to two additional types of defects: metal-hydrogen defects, acting as acceptors, and oxygen-hydrogen defects, acting as donors. The impact of these defects is linked to different instabilities observed in a-IGZO. Specifically, the diffusion of hydrogen and oxygen is connected to positive-and negative-bias stresses, while negative-bias illumination stress originates from the formation of peroxides. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000433070900003 |
Publication Date |
2018-05-25 |
Series Editor |
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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 |
2331-7019 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.808 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 4.808 |
Call Number |
UA @ lucian @ c:irua:151497 |
Serial |
5019 |
Permanent link to this record |
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Author |
Mees, M.J.; Pourtois, G.; Neyts, E.C.; Thijsse, B.J.; Stesmans, A. |
Title |
Uniform-acceptance force-bias Monte Carlo method with time scale to study solid-state diffusion |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
13 |
Pages |
134301-134301,9 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Monte Carlo (MC) methods have a long-standing history as partners of molecular dynamics (MD) to simulate the evolution of materials at the atomic scale. Among these techniques, the uniform-acceptance force-bias Monte Carlo (UFMC) method [ G. Dereli Mol. Simul. 8 351 (1992)] has recently attracted attention [ M. Timonova et al. Phys. Rev. B 81 144107 (2010)] thanks to its apparent capacity of being able to simulate physical processes in a reduced number of iterations compared to classical MD methods. The origin of this efficiency remains, however, unclear. In this work we derive a UFMC method starting from basic thermodynamic principles, which leads to an intuitive and unambiguous formalism. The approach includes a statistically relevant time step per Monte Carlo iteration, showing a significant speed-up compared to MD simulations. This time-stamped force-bias Monte Carlo (tfMC) formalism is tested on both simple one-dimensional and three-dimensional systems. Both test-cases give excellent results in agreement with analytical solutions and literature reports. The inclusion of a time scale, the simplicity of the method, and the enhancement of the time step compared to classical MD methods make this method very appealing for studying the dynamics of many-particle systems. |
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 |
000302290500001 |
Publication Date |
2012-04-03 |
Series Editor |
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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 |
31 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:97160 |
Serial |
3809 |
Permanent link to this record |
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Author |
Scarrozza, M.; Pourtois, G.; Houssa, M.; Heyns, M.; Stesmans, A. |
Title |
Oxidation of the GaAs(001) surface : insights from first-principles calculations |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
19 |
Pages |
195307-195307,8 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We performed a detailed investigation of the oxidation of the technologically relevant GaAs(001)-beta 2(2x4) surface via density functional calculations. The purpose is to gain insights on the atomistic mechanisms and local bondings that underlie the degradation of the surface properties once exposed to oxygen. The study comprises the adsorption of single O atoms, through the sampling of several adsorption sites, and the subsequent formation of the O adsorbate at increasing coverage by taking into account multiple-atom adsorption. Based on the evaluation of the energetics and the structural properties of the atomistic models generated, the results here reported delineate a consistent picture of the initial stage of the surface oxidation: (i) at low coverage, in the limit of single O insertions, oxygen is incorporated on the surface forming a twofold-bridging Ga-O-As bond; (ii) at increasing coverage, as multiple O atoms are involved, this is accompanied by the formation of a threefold-coordinated bond (with two Ga and one As atoms); (iii) the latter has important implications regarding the electronic properties of the adsorbate since this O bonding may result in the formation of As dangling bonds. Moreover, a clear trend of increased energy gain for the incorporation of neighboring O atoms compared to single O insertions indicates that the formation of oxide clusters is favored over a regime of uniform oxidation. Our findings provide a detailed description of the O bonding and stress the importance of modeling the adsorption of multiple O atoms for an accurate description of the surface oxidation. |
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 |
000303755700006 |
Publication Date |
2012-05-08 |
Series Editor |
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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 |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:99122 |
Serial |
2538 |
Permanent link to this record |
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Author |
Nishio, K.; Lu, A.K.A.; Pourtois, G. |
Title |
Low-strain Si/O superlattices with tunable electronic properties : ab initio calculations |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
165303 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We propose that low-strain Si/O superlattices can be constructed by connecting reconstructed Si{001} surfaces by Si-O-Si bridges. Ab initio calculations show that our models are energetically more favorable than all the models proposed so far. The part of our Si/O superlattice model is experimentally accessible just by oxidizing a Si( 001) substrate. To complete our Si/O superlattice model, we propose a three-step method. We also explore the potential of our Si/O superlattice models for new materials used in future Si electronics. We find that the location of the channel where the carriers travel can be controlled between the interfaces and the Si layers by the insertion of O atoms into the Si-Si dimers. By revealing the origins of the interface electron and hole states, we find that similar interface states should be easily achieved for Si slabs and Si substrates. Interestingly, the interface electrons and holes have small effective masses in the direction parallel to the channel and large effective masses in the direction normal to the channel, which makes the Si/O superlattices attractive to be used for channel materials. We also find that the valley splitting of Si is enhanced by the formation of the Si/O/Si interfaces, which is ideal for developing Si-based qubits. Our findings open new perspectives to design and control the electronic properties of Si. |
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 |
000352986700002 |
Publication Date |
2015-04-16 |
Series Editor |
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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 |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:125998 |
Serial |
1852 |
Permanent link to this record |