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Author Houssa, M.; Scalise, E.; Sankaran, K.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. doi  openurl
  Title Electronic properties of hydrogenated silicene and germanene Type A1 Journal article
  Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 98 Issue 22 Pages 223107  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The electronic properties of hydrogenated silicene and germanene, so called silicane and germanane, respectively, are investigated using first-principles calculations based on density functional theory. Two different atomic configurations are found to be stable and energetically degenerate. Upon the adsorption of hydrogen, an energy gap opens in silicene and germanene. Their energy gaps are next computed using the HSE hybrid functional as well as the G(0)W(0) many-body perturbation method. These materials are found to be wide band-gap semiconductors, the type of gap in silicane (direct or indirect) depending on its atomic configuration. Germanane is predicted to be a direct-gap material, independent of its atomic configuration, with an average energy gap of about 3.2 eV, this material thus being potentially interesting for optoelectronic applications in the blue/violet spectral range. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3595682]  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000291405700057 Publication Date 2011-06-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 63 Open Access  
  Notes Approved Most recent IF: 3.411; 2011 IF: 3.844  
  Call Number UA @ lucian @ c:irua:105586 Serial 1003  
Permanent link to this record
 

 
Author Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. doi  openurl
  Title Electronic properties of two-dimensional hexagonal germanium Type A1 Journal article
  Year 2010 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 96 Issue 8 Pages 082111,1-082111,3  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The electronic properties of two-dimensional hexagonal germanium, so called germanene, are investigated using first-principles simulations. Consistent with previous reports, the surface is predicted to have a poor metallic behavior, i.e., being metallic with a low density of states at the Fermi level. It is found that biaxial compressively strained germanene is a gapless semiconductor with linear energy dispersions near the K pointslike graphene. The calculated Fermi velocity of germanene is almost independent of the strain and is about 1.7×10<sup>6</sup> m/s, quite comparable to the value in graphene.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000275027200044 Publication Date 2010-02-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 86 Open Access  
  Notes Approved Most recent IF: 3.411; 2010 IF: 3.841  
  Call Number UA @ lucian @ c:irua:91716 Serial 1004  
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Author Sankaran, K.; Pourtois, G.; Degraeve, R.; Zahid, M.B.; Rignanese, G.-M.; Van Houdt, J. doi  openurl
  Title First-principles modeling of intrinsic and extrinsic defects in \gamma-Al2O3 Type A1 Journal article
  Year 2010 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 97 Issue 21 Pages 212906  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The electronic properties of a set of intrinsic and extrinsic point defects in gamma-Al2O3 are investigated using quasiparticle calculations within the G(0)W(0) approximation. We find that the electronic signature of atomic vacancies lie deep in the band gap, close to the top of the valence band edge. The introduction of C, Si, and N impurities induces defective levels that are located close to the conduction band edge and near the middle of the band gap of the oxide. The comparison with electrical measurements reveals that the energy levels of some of these defects match with the electronic fingerprint of the defects reported in gamma-Al2O3 based nonvolatile memories. (C) 2010 American Institute of Physics. [doi:10.1063/1.3507385]  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000284618300039 Publication Date 2010-11-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 12 Open Access  
  Notes Approved Most recent IF: 3.411; 2010 IF: 3.841  
  Call Number UA @ lucian @ c:irua:105617 Serial 1213  
Permanent link to this record
 

 
Author Clima, S.; Chen, Y.Y.; Degraeve, R.; Mees, M.; Sankaran, K.; Govoreanu, B.; Jurczak, M.; De Gendt, S.; Pourtois, G. doi  openurl
  Title First-principles simulation of oxygen diffusion in HfOx : role in the resistive switching mechanism Type A1 Journal article
  Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 100 Issue 13 Pages 133102-133102,4  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Transition metal oxide-based resistor random access memory (RRAM) takes advantage of oxygen-related defects in its principle of operation. Since the change in resistivity of the material is controlled by the oxygen deficiency level, it is of major importance to quantify the kinetics of the oxygen diffusion, key factor for oxide stoichiometry. Ab initio accelerated molecular dynamics techniques are employed to investigate the oxygen diffusivity in amorphous hafnia (HfOx, x = 1.97, 1.0, 0.5). The computed kinetics is in agreement with experimental measurements. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3697690]  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000302230800060 Publication Date 2012-03-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 63 Open Access  
  Notes Approved Most recent IF: 3.411; 2012 IF: 3.794  
  Call Number UA @ lucian @ c:irua:97786 Serial 1214  
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Author Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. doi  openurl
  Title Inelastic electron tunneling spectroscopy of HfO2 gate stacks : a study based on first-principles modeling Type A1 Journal article
  Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 99 Issue 13 Pages 132101,1-132101,3  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract A first-principles modeling approach is used to investigate the vibrational properties of HfO2. The calculated phonon density of states is compared to experimental results obtained from inelastic electron tunneling spectroscopy (IETS) of various metal-oxide-semiconductor devices with HfO2 gate stacks. This comparison provides deep insights into the nature of the signatures of the complicated IETS spectra and provides valuable structural information about the gate stack, such as the possible presence of oxygen vacancies in jet-vapour deposited HfO2. Important structural differences between the interface of atomic-layer or molecular-beam deposited HfO2 and the Si substrate are also revealed.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000295618000036 Publication Date 2011-09-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 1 Open Access  
  Notes Approved Most recent IF: 3.411; 2011 IF: 3.844  
  Call Number UA @ lucian @ c:irua:93611 Serial 1606  
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Author Chen, Y.Y.; Pourtois, G.; Adelmann, C.; Goux, L.; Govoreanu, B.; Degreave, R.; Jurczak, M.; Kittl, J.A.; Groeseneken, G.; Wouters, D.J. doi  openurl
  Title Insights into Ni-filament formation in unipolar-switching Ni/HfO2/TiN resistive random access memory device Type A1 Journal article
  Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 100 Issue 11 Pages 113513-113513,4  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this letter, CMOS-compatible Ni/HfO2/TiN resistive random access memory stacks demonstrated attractive unipolar switching properties, showing >10(3) endurance and long retention at 150 degrees C. The Ni bottom electrode (BE) improved the switching yield over the NiSiPt BE. To better understand the unipolar forming mechanism, ab initio simulation and time of flight-secondary ion mass spectroscopy were utilized. Compared to the NiSiPt BE, Ni BE gives larger Ni diffusion in the HfO2 and lower formation enthalpy of Ni2+ species during electrical forming. Both the electrical and physical results supported a Ni-injection mechanism for the filament formation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3695078]  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000302204900091 Publication Date 2012-03-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 29 Open Access  
  Notes Approved Most recent IF: 3.411; 2012 IF: 3.794  
  Call Number UA @ lucian @ c:irua:98295 Serial 1674  
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Author Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. doi  openurl
  Title Structural and vibrational properties of amorphous GeO2 from first-principles Type A1 Journal article
  Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 98 Issue 20 Pages 202110,1-202110,3  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The structural and vibrational properties of amorphous germanium oxide (a-GeO<sub>2</sub>) are investigated using first-principles calculations based on density functional theory. We first generate an a-GeO<sub>2</sub> structure by first-principles molecular dynamics and analyze its structural properties. The vibrational spectra is then calculated within a density-functional approach. Both static and dynamic properties are in good agreement with experimental data. We next generate defects in our structure (oxygen vacancies with several density and charge states) and consider the most stable atomic configurations, focusing on the vibrational features of threefold coordinated O and divalent Ge centers.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000290812100038 Publication Date 2011-05-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 226 Open Access  
  Notes Approved Most recent IF: 3.411; 2011 IF: 3.844  
  Call Number UA @ lucian @ c:irua:90222 Serial 3202  
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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.; url  doi
openurl 
  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 (up) 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  
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Author Lu, A.K.A.; Pourtois, G.; Agarwal, T.; Afzalian, A.; Radu, I.P.; Houssa, M. doi  openurl
  Title Origin of the performances degradation of two-dimensional-based metal-oxide-semiconductor field effect transistors in the sub-10 nm regime: A first-principles study Type A1 Journal article
  Year 2016 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 108 Issue 4 Pages 043504  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The impact of the scaling of the channel length on the performances of metal-oxide-semiconductor field effect transistors, based on two-dimensional (2D) channel materials, is theoretically investigated, using density functional theory combined with the non-equilibrium Green's function method. It is found that the scaling of the channel length below 10nm leads to strong device performance degradations. Our simulations reveal that this degradation is essentially due to the tunneling current flowing between the source and the drain in these aggressively scaled devices. It is shown that this electron tunneling process is modulated by the effective mass of the 2D channel material, and sets the limit of the scaling in future transistor designs. (C) 2016 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000375217200061 Publication Date 2016-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 4 Open Access  
  Notes Approved Most recent IF: 3.411  
  Call Number UA @ lucian @ c:irua:144750 Serial 4677  
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Author Guo, J.; Clima, S.; Pourtois, G.; Van Houdt, J. doi  openurl
  Title Identifying alternative ferroelectric materials beyond Hf(Zr)O-₂ Type A1 Journal article
  Year 2020 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett  
  Volume 117 Issue 26 Pages 262903  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract A database-driven approach combined with ab initio density functional theory (DFT) simulations is used to identify and simulate alternative ferroelectric materials beyond Hf(Zr)O-2. The database-driven screening method identifies a class of wurtzite ferroelectric materials. DFT simulations of wurtzite magnesium chalcogenides, including MgS, MgSe, and MgTe, show their potential to achieve improved ferroelectric (FE) stability, simple atomistic unit cell structure, and large FE polarization. Strain engineering can effectively modulate the FE switching barrier height for facilitating FE switching. The effect of the piezoelectric property on the FE switching barrier heights is also examined.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000608049700003 Publication Date 2020-12-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4 Times cited Open Access  
  Notes Approved Most recent IF: 4; 2020 IF: 3.411  
  Call Number UA @ admin @ c:irua:176053 Serial 6766  
Permanent link to this record
 

 
Author Clima, S.; Wouters, D.J.; Adelmann, C.; Schenk, T.; Schroeder, U.; Jurczak, M.; Pourtois, G. doi  openurl
  Title Identification of the ferroelectric switching process and dopant-dependent switching properties in orthorhombic HfO2 : a first principles insight Type A1 Journal article
  Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 104 Issue 9 Pages 092906  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The origin of the ferroelectric polarization switching in orthorhombic HfO2 has been investigated by first principles calculations. The phenomenon can be regarded as being the coordinated displacement of four O ions in the orthorhombic unit cell, which can lead to a saturated polarization as high as 53 mu C/cm(2). We show the correlation between the computed polarization reversal barrier and the experimental coercive fields. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000332729200078 Publication Date 2014-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 79 Open Access  
  Notes Approved Most recent IF: 3.411; 2014 IF: 3.302  
  Call Number UA @ lucian @ c:irua:116873 Serial 1550  
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Author Neyts, E.; Maeyens, A.; Pourtois, G.; Bogaerts, A. doi  openurl
  Title A density-functional theory simulation of the formation of Ni-doped fullerenes by ion implantation Type A1 Journal article
  Year 2011 Publication Carbon Abbreviated Journal Carbon  
  Volume 49 Issue 3 Pages 1013-1017  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Using self-consistent KohnSham density-functional theory molecular dynamics simulations, we demonstrate the theoretical possibility to synthesize NiC60, the incarfullerene Ni@C60 and the heterofullerene C59Ni in an ion implantation setup. The corresponding formation mechanisms of all three complexes are elucidated as a function of the ion implantation energy and impact location, suggesting possible routes for selectively synthesizing these complexes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000286683500032 Publication Date 2010-11-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.337 Times cited 13 Open Access  
  Notes Approved Most recent IF: 6.337; 2011 IF: 5.378  
  Call Number UA @ lucian @ c:irua:85139 Serial 639  
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Author Schoeters, B.; Leenaerts, O.; Pourtois, G.; Partoens, B. pdf  url
doi  openurl
  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  
  Corporate Author Thesis  
  Publisher 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 (up) 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  
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Author Clima, S.; Chen, Y.Y.; Chen, C.Y.; Goux, L.; Govoreanu, B.; Degraeve, R.; Fantini, A.; Jurczak, M.; Pourtois, G. url  doi
openurl 
  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 (up) 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 Dutta, S.; Sankaran, K.; Moors, K.; Pourtois, G.; Van Elshocht, S.; Bommels, J.; Vandervorst, W.; Tokei, Z.; Adelmann, C. doi  openurl
  Title Thickness dependence of the resistivity of platinum-group metal thin films Type A1 Journal article
  Year 2017 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 122 Issue 2 Pages 025107  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract We report on the thin film resistivity of several platinum-group metals (Ru, Pd, Ir, and Pt). Platinum-group thin films show comparable or lower resistivities than Cu for film thicknesses below about 5 nm due to a weaker thickness dependence of the resistivity. Based on experimentally determined mean linear distances between grain boundaries as well as ab initio calculations of the electron mean free path, the data for Ru, Ir, and Cu were modeled within the semiclassical Mayadas-Shatzkes model [Phys. Rev. B 1, 1382 (1970)] to assess the combined contributions of surface and grain boundary scattering to the resistivity. For Ru, the modeling results indicated that surface scattering was strongly dependent on the surrounding material with nearly specular scattering at interfaces with SiO2 or air but with diffuse scattering at interfaces with TaN. The dependence of the thin film resistivity on the mean free path is also discussed within the Mayadas-Shatzkes model in consideration of the experimental findings. Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000405663800038 Publication Date 2017-07-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 42 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ lucian @ c:irua:145213 Serial 4729  
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Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. pdf  url
doi  openurl
  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 (up) 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  
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Author Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Loo, R.; Vandervorst, W. pdf  doi
openurl 
  Title Evolution of phosphorus-vacancy clusters in epitaxial germanium Type A1 Journal article
  Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 125 Issue 2 Pages 025701  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The E centers (dopant-vacancy pairs) play a significant role in dopant deactivation in semiconductors. In order to gain insight into dopant-defect interactions during epitaxial growth of in situ phosphorus doped Ge, positron annihilation spectroscopy, which is sensitive to open-volume defects, was performed on Ge layers grown by chemical vapor deposition with different concentrations of phosphorus (similar to 1 x 10(18)-1 x 10(20) cm(-3)). Experimental results supported by first-principles calculations based on the two component density-functional theory gave evidence for the existence of mono-vacancies decorated by several phosphorus atoms as the dominant defect type in the epitaxial Ge. The concentration of vacancies increases with the amount of P-doping. The number of P atoms around the vacancy also increases, depending on the P concentration. The evolution of P-n-V clusters in Ge contributes significantly to the dopant deactivation. Published under license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000455922100057 Publication Date 2019-01-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 5 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:156722 Serial 5274  
Permanent link to this record
 

 
Author Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Porret, C.; Loo, R.; Vandervorst, W. url  doi
openurl 
  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  
  Corporate Author 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 (up) 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
 

 
Author Khanam, A.; Vohra, A.; Slotte, J.; Makkonen, I.; Loo, R.; Pourtois, G.; Vandervorst, W. url  doi
openurl 
  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  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000536196000003 Publication Date 2020-05-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.2 Times cited Open Access  
  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
 

 
Author Lu, A.K.A.; Pourtois, G.; Luisier, M.; Radu, I.P.; Houssa, M. url  doi
openurl 
  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  
  Corporate Author Thesis  
  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 (up) 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 Mehta, A.N.; Zhang, H.; Dabral, A.; Richard, O.; Favia, P.; Bender, H.; Delabie, A.; Caymax, M.; Houssa, M.; Pourtois, G.; Vandervorst, W. pdf  doi
openurl 
  Title Structural characterization of SnS crystals formed by chemical vapour deposition Type A1 Journal article
  Year 2017 Publication Journal of microscopy T2 – 20th International Conference on Microscopy of Semiconducting Materials, (MSM), APR 09-13, 2017, Univ Oxford, Univ Oxford, Oxford, ENGLAND Abbreviated Journal J Microsc-Oxford  
  Volume 268 Issue 3 Pages 276-287  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract <script type='text/javascript'>document.write(unpmarked('The crystal and defect structure of SnS crystals grown using chemical vapour deposition for application in electronic devices are investigated. The structural analysis shows the presence of two distinct crystal morphologies, that is thin flakes with lateral sizes up to 50 m and nanometer scale thickness, and much thicker but smaller crystallites. Both show similar Raman response associated with SnS. The structural analysis with transmission electron microscopy shows that the flakes are single crystals of -SnS with [010] normal to the substrate. Parallel with the surface of the flakes, lamellae with varying thickness of a new SnS phase are observed. High-resolution transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), first-principles simulations (DFT) and nanobeam diffraction (NBD) techniques are employed to characterise this phase in detail. DFT results suggest that the phase is a strain stabilised \u0027 one grown epitaxially on the -SnS crystals. TEM analysis shows that the crystallites are also -SnS with generally the [010] direction orthogonal to the substrate. Contrary to the flakes the crystallites consist of two to four grains which are tilted up to 15 degrees relative to the substrate. The various grain boundary structures and twin relations are discussed. Under high-dose electron irradiation, the SnS structure is reduced and -Sn formed. It is shown that this damage only occurs for SnS in direct contact with SiO2. Lay description SnS is a p-type semiconductor, which has attracted significant interest for electronic devices due to its unique properties, low-toxicity and abundance of Sn in nature. Although in the past it has been most extensively studied as the absorber material in solar cells, it has recently garnered interest for application as a p-type two-dimensional semiconductor in nanoelectronic devices due to its anisotropic layered structure similar to the better known phosphorene. Tin sulphide can take the form of several phases and the electronic properties of the material depend strongly on its crystal structure. It is therefore crucial to study the crystal structure of the material in order to predict the electronic properties and gain insight into the growth mechanism. In this work, SnS crystals deposited using a chemical vapour deposition technique are investigated extensively for their crystal and defect structure using transmission electron microscopy (TEM) and related techniques. We find the presence of two distinct crystal morphologies, that is thin flakes with lateral sizes up to 50 m and nm scale thickness, and much thicker but smaller crystallites. The flakes are single crystals of -SnS and contain lamellae with varying thickness of a different phase which appear to be -SnS at first glance. High-resolution scanning transmission electron microscopy is used to characterise these lamellae where the annular bright field (ABF) mode better reveals the position of the sulphur columns. The sulphur columns in the lamellae are found to be shifted relative to the -SnS structure which indicates the formation of a new phase which is a distorted version of the phase which we tentatively refer to as \u0027-SnS. Simulations based on density functional theory (DFT) are used to model the interface and a similar shift of sulphur columns in the -SnS layer is observed which takes place as a result of strong interaction at the interface between the two phases resulting in strain transfer. Nanobeam electron diffraction (NBD) is used to map the lattice mismatch in the thickness of the flakes which reveals good in-plane matching and some expansion out-of-plane in the lamellae. Contrary to the flakes the crystallites are made solely of -SnS and consist of two to four grains which are tilted up to 15 degrees relative to the substrate. The various grain boundary structures and twin relations are discussed. At high electron doses, SnS is reduced to -Sn, however the damage occurs only for SnS in direct contact with SiO2.'));  
  Address  
  Corporate Author Thesis  
  Publisher Wiley Place of Publication Hoboken Editor  
  Language Wos 000415900300009 Publication Date 2017-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0022-2720 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.692 Times cited 2 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 1.692  
  Call Number UA @ lucian @ c:irua:147692 Serial 4898  
Permanent link to this record
 

 
Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. pdf  doi
openurl 
  Title Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor : structure, tail states and strain effects Type A1 Journal article
  Year 2015 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 48 Issue 48 Pages 435104  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced variation in the effective mass is found to be negligible (less than 1%).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000365876300012 Publication Date 2015-09-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.588 Times cited 23 Open Access  
  Notes Approved Most recent IF: 2.588; 2015 IF: 2.721  
  Call Number UA @ lucian @ c:irua:130277 Serial 4153  
Permanent link to this record
 

 
Author Hardy, A.; Van Elshocht, S.; De Dobbelaere, C.; Hadermann, J.; Pourtois, G.; De Gendt, S.; Afanas'ev, V.V.; Van Bael, M.K. pdf  doi
openurl 
  Title Properties and thermal stability of solution processed ultrathin, high-k bismuth titanate (Bi2Ti2O7) films Type A1 Journal article
  Year 2012 Publication Materials research bulletin Abbreviated Journal Mater Res Bull  
  Volume 47 Issue 3 Pages 511-517  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Ultrathin bismuth titanate films (Bi2Ti2O7, 5-25 nm) are deposited onto SiO2/Si substrates by aqueous chemical solution deposition and their evolution during annealing is studied. The films crystallize into a preferentially oriented, pure pyrochlore phase between 500 and 700 degrees C, depending on the film thickness and the total thermal budget. Crystallization causes a strong increase of surface roughness compared to amorphous films. An increase of the interfacial layer thickness is observed after anneal at 600 degrees C, together with intermixing of bismuth with the substrate as shown by TEM-EDX. The band gap was determined to be similar to 3 eV from photoconductivity measurements and high dielectric constants between 30 and 130 were determined from capacitance voltage measurements, depending on the processing conditions. (C) 2012 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000301994100001 Publication Date 2012-01-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0025-5408; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.446 Times cited Open Access  
  Notes Approved Most recent IF: 2.446; 2012 IF: 1.913  
  Call Number UA @ lucian @ c:irua:97797 Serial 2727  
Permanent link to this record
 

 
Author Pham, A.-T.; Zhao, Q.-T.; Jungemann, C.; Meinerzhagen, B.; Mantl, S.; Sorée, B.; Pourtois, G. pdf  doi
openurl 
  Title Comparison of strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs : CV characteristics, mobility, and ON current Type A1 Journal article
  Year 2011 Publication Solid state electronics Abbreviated Journal Solid State Electron  
  Volume 65-66 Issue Pages 64-71  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs are investigated including important aspects like CV characteristics, mobility, and ON current. The simulations are based on the self-consistent solution of 6 × 6 k · p Schrödinger Equation, multi subband Boltzmann Transport Equation and Poisson Equation, and capture size quantization, strain, crystallographic orientation, and SiGe alloy effects on a solid physical basis. The simulation results are validated by comparison with different experimental data sources. The simulation results show that the strained SiGe HOI PMOSFET with (1 1 0) surface orientation has a higher gate capacitance and a much higher mobility and ON current compared to a similar device with the traditional (0 0 1) surface orientation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000297182700012 Publication Date 2011-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0038-1101; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.58 Times cited 2 Open Access  
  Notes ; ; Approved Most recent IF: 1.58; 2011 IF: 1.397  
  Call Number UA @ lucian @ c:irua:92866 Serial 433  
Permanent link to this record
 

 
Author Pham, A.-T.; Sorée, B.; Magnus, W.; Jungemann, C.; Meinerzhagen, B.; Pourtois, G. pdf  doi
openurl 
  Title Quantum simulations of electrostatics in Si cylindrical junctionless nanowire nFETs and pFETs with a homogeneous channel including strain and arbitrary crystallographic orientations Type A1 Journal article
  Year 2012 Publication Solid state electronics Abbreviated Journal Solid State Electron  
  Volume 71 Issue Pages 30-36  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Simulation results of electrostatics in Si cylindrical junctionless nanowire transistors with a homogenous channel are presented. Junctionless transistors including strain and arbitrary crystallographic orientations are studied. Size quantization effects are simulated by self-consistent solutions of the Poisson and Schrodinger equations. The 6 x 6 k.p method is employed for the calculation of the valence subband structure in a junctionless nanowire pFET. The influence of stress/strain and crystallographic channel orientation on to the electrostatics in terms of subband structure, charge density, and C-V curve is systematically studied. (C) 2011 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000303033800007 Publication Date 2011-12-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0038-1101; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.58 Times cited 2 Open Access  
  Notes ; ; Approved Most recent IF: 1.58; 2012 IF: 1.482  
  Call Number UA @ lucian @ c:irua:98245 Serial 2786  
Permanent link to this record
 

 
Author Clima, S.; Garbin, D.; Devulder, W.; Keukelier, J.; Opsomer, K.; Goux, L.; Kar, G.S.; Pourtois, G. pdf  doi
openurl 
  Title Material relaxation in chalcogenide OTS SELECTOR materials Type A1 Journal article
  Year 2019 Publication Microelectronic engineering Abbreviated Journal Microelectron Eng  
  Volume 215 Issue 215 Pages 110996  
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Nature of the mobility-gap states in amorphous Ge-rich Ge50Se50 was found to be related to homopolar Ge bonds in the chains/clusters of Ge atoms. Threshold switching material suffers Ge-Ge bond concentration drift during material ageing, which can explain the observed reliability of the aGe(50)Se(50) selector devices. Strong Ge-N bonds were introduced to alleviate the observed instability.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000480665600008 Publication Date 2019-05-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0167-9317 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.806 Times cited 1 Open Access  
  Notes Approved Most recent IF: 1.806  
  Call Number UA @ admin @ c:irua:161905 Serial 6308  
Permanent link to this record
 

 
Author Pourtois, G.; Lauwers, A.; Kittl, J.; Pantisano, L.; Sorée, B.; De Gendt, S.; Magnus, W.; Heyns, A.; Maex, K. pdf  doi
openurl 
  Title First-principle calculations on gate/dielectric interfaces : on the origin of work function shifts Type A1 Journal article
  Year 2005 Publication Microelectronic engineering Abbreviated Journal Microelectron Eng  
  Volume 80 Issue Pages 272-279  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The impact of interfacial chemistry occurring at dielectric/gate interface of P-MOS and N-MOS devices is reviewed through a quick literature survey. A specific emphasis is put on the way the bond polarization that occurs between a dielectric and a metal substrate impacts on the gate work function. First-principle simulations are then used to study the work function changes induced by dopant aggregation in nickel monosilicide metal gates. It is shown that the changes are a natural consequence of the variation of the interface polarization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000231517000062 Publication Date 2005-06-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0167-9317; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.806 Times cited 31 Open Access  
  Notes Approved Most recent IF: 1.806; 2005 IF: 1.347  
  Call Number UA @ lucian @ c:irua:95095 Serial 1199  
Permanent link to this record
 

 
Author Clima, S.; Govoreanu, B.; Jurczak, M.; Pourtois, G. pdf  doi
openurl 
  Title HfOx as RRAM material : first principles insights on the working principles Type A1 Journal article
  Year 2014 Publication Microelectronic engineering Abbreviated Journal Microelectron Eng  
  Volume 120 Issue Pages 13-18  
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract First-principles simulations were employed to gain atomistic insights on the working principles of amorphous HfO2 based Resistive Random Access Memory stack: the nature of the defect responsible for the switching between the High and Low Resistive States has been unambiguously identified to be the substoichiometric Hf sites (commonly called oxygen vacancy-V-O) and the kinetics of the process have been investigated through the study of O diffusion. Also the role of each material layer in the TiN/HfO2/Hf/TiN RRAM stack and the impact of the deposition techniques have been examined: metallic Hf sputtering is needed to provide an oxygen exchange layer that plays the role of defect buffer. TiN shall be a good defect barrier for O but a bad defect buffer layer. A possible scenario to explain the device degradation (switching failure) mechanism has been proposed – the relaxation of the metastable amorphous phase towards crystalline structure leads to denser, more structured cluster that can increase the defect migration barriers. (C) 2013 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000336697300004 Publication Date 2013-08-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0167-9317; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.806 Times cited 22 Open Access  
  Notes Approved Most recent IF: 1.806; 2014 IF: 1.197  
  Call Number UA @ lucian @ c:irua:117767 Serial 3535  
Permanent link to this record
 

 
Author van den Broek, B.; Houssa, M.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. doi  openurl
  Title First-principles electronic functionalization of silicene and germanene by adatom chemisorption Type A1 Journal article
  Year 2014 Publication Applied surface science Abbreviated Journal Appl Surf Sci  
  Volume 291 Issue Pages 104-108  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract This study presents first-principles results on the electronic functionalization of silicene and germanene monolayers by means of chemisorption of adatom species H, Li, F, Sc, Ti, V. Three general adatom-monolayer configurations are considered, each having its distinct effect on the electronic structure, yielding metallic or semiconducting dispersions depending on the adatom species and configuration. The induced bandgap is a (in)direct F gap ranging from 0.2 to 2.3 eV for both silicene and germanene. In general the alternating configuration was found to be the most energetically stable. The boatlike and chairlike conformers are degenerate with the former having anisotropic effective carrier masses. The top configuration leads to the planar monolayer and predominately to a gapped dispersion. The hollow configuration with V adatoms retains the Dirac cone, but with strong orbital planar hybridization at the Fermi level. We also observe a planar surface state the Fermi level for the latter systems. (C) 2013 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000329327700023 Publication Date 2013-09-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0169-4332; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.387 Times cited 32 Open Access  
  Notes Approved Most recent IF: 3.387; 2014 IF: 2.711  
  Call Number UA @ lucian @ c:irua:113766 Serial 1208  
Permanent link to this record
 

 
Author Houssa, M.; van den Broek, B.; Scalise, E.; Ealet, B.; Pourtois, G.; Chiappe, D.; Cinquanta, E.; Grazianetti, C.; Fanciulli, M.; Molle, A.; Afanas’ev, V.V.; Stesmans, A.; doi  openurl
  Title Theoretical aspects of graphene-like group IV semiconductors Type A1 Journal article
  Year 2014 Publication Applied surface science Abbreviated Journal Appl Surf Sci  
  Volume 291 Issue Pages 98-103  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Silicene and germanene are the silicon and germanium counterparts of graphene, respectively. Recent experimental works have reported the growth of silicene on (1 1 1)Ag surfaces with different atomic configurations, depending on the growth temperature and surface coverage. We first theoretically study the structural and electronic properties of silicene on (1 1 1) Ag surfaces, focusing on the (4 x 4) silicene/Ag structure. Due to symmetry breaking in the silicene layer (nonequivalent number of top and bottom Si atoms), the corrugated silicene layer, with the Ag substrate removed, is predicted to be semiconducting, with a computed energy bandgap of about 0.3 eV. However, the hybridization between the Si 3p orbitals and the Ag 5s orbital in the silicene/(1 1 1)Ag slab model leads to an overall metallic system, with a distribution of local electronic density of states, which is related to the slightly disordered structure of the silicene layer on the (1 1 1)Ag surface. We next study the interaction of silicene and germanene with different hexagonal non-metallic substrates, namely ZnS and ZnSe. On reconstructed (0 0 0 1)ZnS or ZnSe surfaces, which should be more energetically stable for very thin layers, silicene and germanene are found to be semiconducting. Remarkably, the nature and magnitude of their energy bandgap can be controlled by an out-of-plane electric field, an important finding for the potential use of these materials in nanoelectronic devices. (C) 2013 Elsevier B. V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000329327700022 Publication Date 2013-09-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0169-4332; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.387 Times cited 20 Open Access  
  Notes Approved Most recent IF: 3.387; 2014 IF: 2.711  
  Call Number UA @ lucian @ c:irua:113765 Serial 3603  
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