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	Author	Mehta, A.N.; Zhang, H.; Dabral, A.; Richard, O.; Favia, P.; Bender, H.; Delabie, A.; Caymax, M.; Houssa, M.; Pourtois, G.; Vandervorst, W.
	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	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	Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
	Title	First-principles study of strained 2D MoS₂			Type	A1 Journal article
	Year	2014	Publication	Physica. E: Low-dimensional systems and nanostructures	Abbreviated Journal	Physica E
	Volume	56	Issue		Pages	416-421
	Keywords	A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The electronic and vibrational properties of 2D honeycomb structures of molybdenum disulfide (MoS2) subjected to strain have been investigated using first-principles calculations based on density functional theory. We have studied the evolution of the electronic properties of bulk and layered MoS2, going down from a few layers up to a mono-layer, and next investigated the effect of bi-axial strain on their electronic structure and vibrational frequencies. Both for tensile and compressive biaxial strains, the shrinking of the energy band-gap of MoS2 with increasing level of applied strain is observed and a transition limit of the system from semiconducting to metallic is predicted to occur for strains in the range of 8-10%. We also found a progressive downshift (upshift) of both the E-2g(1) and A(1g) Raman active modes with increasing level of applied tensile (compressive) strain. Interestingly, significant changes in the curvature of the conduction and valence band near their extrema upon the application of strain are also predicted, with correlated variations of the electron and hole effective masses. These changes present interesting possibilities for engineering the electronic properties of 2D structures of MoS2. (C) 2012 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher	North-Holland	Place of Publication	Amsterdam	Editor
	Language		Wos	000330815800070	Publication Date	2012-08-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1386-9477;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.221	Times cited	72	Open Access
	Notes				Approved	Most recent IF: 2.221; 2014 IF: 2.000
	Call Number	UA @ lucian @ c:irua:115761			Serial	1220
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	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
	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
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	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
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	Author	van den Broek, B.; Houssa, M.; Iordanidou, K.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
	Title	Functional silicene and stanene nanoribbons compared to graphene: electronic structure and transport			Type	A1 Journal article
	Year	2016	Publication	2D materials	Abbreviated Journal	2D Mater
	Volume	3	Issue	1	Pages	015001
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Since the advent of graphene, other 2D materials have garnered interest; notably the single element materials silicene, germanene, and stanene. Weinvestigate the ballistic current-voltage (I-V) characteristics of armchair silicene and stanene armchair nanoribbons (AXNRs with X = Si, Sn) using a combination of density functional theory and non-equilibrium Green's functions. The impact of out-of-plane electric field and in-plane uniaxial strain on the ribbon geometries, electronic structure, and (I-V)s are considered and contrasted with graphene. Since silicene and stanene are sp(2)/sp(3) buckled layers, the electronic structure can be tuned by an electric field that breaks the sublattice symmetry, an effect absent in graphene. This decreases the current by similar to 50% for Sn, since it has the largest buckling. Uniaxial straining of the ballistic channel affects the AXNR electronic structure in multiple ways: it changes the bandgap and associated effective carrier mass, and creates a local buckling distortion at the lead-channel interface which induces a interface dipole. Due to the increasing sp(3) hybridization character with increasing element mass, large reconstructions rectify the strained systems, an effect absent in sp(2) bonded graphene. This results in a smaller strain effect on the current: a decrease of 20% for Sn at 15% tensile strain compared to a similar to 75% decrease for C.
	Address
	Corporate Author				Thesis
	Publisher	IOP Publishing	Place of Publication	Bristol	Editor
	Language		Wos	000373936300021	Publication Date	2016-01-06
	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	19	Open Access
	Notes				Approved	Most recent IF: 6.937
	Call Number	UA @ lucian @ c:irua:144746			Serial	4658
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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
	Corporate Author				Thesis
	Publisher	Ieee	Place of Publication	New york	Editor
	Language		Wos		Publication Date	0000-00-00
	Series Editor		Series Title		Abbreviated Series Title
	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
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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
	Corporate Author				Thesis
	Publisher	Ieee	Place of Publication	New york	Editor
	Language		Wos		Publication Date	0000-00-00
	Series Editor		Series Title		Abbreviated Series Title
	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:127034			Serial	1149
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	Author	Goux, L.; Fantini, A.; Govoreanu, B.; Kar, G.; Clima, S.; Chen, Y.-Y.; Degraeve, R.; Wouters, D.J.; Pourtois, G.; Jurczak, M.
	Title	Asymmetry and switching phenomenology in TiN\ (Al₂O₃) \ HfO₂ \ Hf systems			Type	A1 Journal article
	Year	2012	Publication	ECS solid state letters	Abbreviated Journal	Ecs Solid State Lett
	Volume	1	Issue	4	Pages	63-65
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this letter, we address the bipolar resistive switching phenomenology in scaled TiN\HfO2\Hf cells. By means of stack engineering using a thin Al2O3 layer inserted either at the TiN\HfO2 or at the Hf\HfO2 interface, we demonstrate that the reset operation takes place close to the TiNanode. Due to the increase of the oxygen-vacancy profile from the TiN to the Hf interface, the filament-confining and wide band-gap Al2O3 layer should indeed be engineered at the interface with the TiN electrode in order to further improve the switching control and to allow reaching larger state resistances. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.003204ssl] All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical society	Place of Publication	Pennington (N.J.)	Editor
	Language		Wos	000318340300005	Publication Date	2012-08-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2162-8742;2162-8750;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.184	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 1.184; 2012 IF: NA
	Call Number	UA @ lucian @ c:irua:108530			Serial	160
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	Author	Delabie, A.; Jayachandran, S.; Caymax, M.; Loo, R.; Maggen, J.; Pourtois, G.; Douhard, B.; Conard, T.; Meersschaut, J.; Lenka, H.; Vandervorst, W.; Heyns, M.;
	Title	Epitaxial chemical vapor deposition of silicon on an oxygen monolayer on Si(100) substrates			Type	A1 Journal article
	Year	2013	Publication	ECS solid state letters	Abbreviated Journal	Ecs Solid State Lett
	Volume	2	Issue	11	Pages	P104-P106
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Crystalline superlattices consisting of alternating periods of Si layers and O-atomic layers are potential new channel materials for scaled CMOS devices. In this letter, we investigate Chemical Vapor Deposition (CVD) for the controlled deposition of O-atoms with O-3 as precursor on Si(100) substrates and Si epitaxy on the O-layer. The O-3 reaction at 50 degrees C on the H-terminated Si results in the formation of Si-OH and/or Si-O-Si-H surface species with monolayer O-content. Defect-free epitaxial growth of Si on an O-layer containing 6.4E+14 O-atoms/cm(2) is achieved from SiH4 at 500 degrees C. (C) 2013 The Electrochemical Society. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical society	Place of Publication	Pennington (N.J.)	Editor
	Language		Wos	000324582600006	Publication Date	2013-09-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2162-8742;2162-8750;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.184	Times cited	12	Open Access
	Notes				Approved	Most recent IF: 1.184; 2013 IF: 0.781
	Call Number	UA @ lucian @ c:irua:111208			Serial	1070
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	Author	Sankaran, K.; Clima, S.; Mees, M.; Pourtois, G.
	Title	Exploring alternative metals to Cu and W for interconnects applications using automated first-principles simulations			Type	A1 Journal article
	Year	2015	Publication	ECS journal of solid state science and technology	Abbreviated Journal	Ecs J Solid State Sc
	Volume	4	Issue	4	Pages	N3127-N3133
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The bulk properties of elementary metals and copper based binary alloys have been investigated using automated first-principles simulations to evaluate their potential to replace copper and tungsten as interconnecting wires in the coming CMOS technology nodes. The intrinsic properties of the screened candidates based on their cohesive energy and on their electronic properties have been used as a metrics to reflect their resistivity and their sensitivity to electromigration. Using these values, the 'performances' of the alloys have been benchmarked with respect to the Cu and W ones. It turns out that for some systems, alloying Cu with another element leads to a reduced tendency to electromigration. This is however done at the expense of a decrease of the conductivity of the alloy with respect to the bulk metal. (C) 2014 The Electrochemical Society. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical society	Place of Publication	Pennington (N.J.)	Editor
	Language		Wos	000349547900018	Publication Date	2014-11-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2162-8769;2162-8777;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.787	Times cited	19	Open Access
	Notes				Approved	Most recent IF: 1.787; 2015 IF: 1.558
	Call Number	c:irua:125296			Serial	1150
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	Author	Loo, R.; Arimura, H.; Cott, D.; Witters, L.; Pourtois, G.; Schulze, A.; Douhard, B.; Vanherle, W.; Eneman, G.; Richard, O.; Favia, P.; Mitard, J.; Mocuta, D.; Langer, R.; Collaert, N.
	Title	Epitaxial CVD Growth of Ultra-Thin Si Passivation Layers on Strained Ge Fin Structures			Type	A1 Journal article
	Year	2018	Publication	ECS journal of solid state science and technology	Abbreviated Journal	Ecs J Solid State Sc
	Volume	7	Issue	2	Pages	P66-P72
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Epitaxially grown ultra-thin Si layers are often used to passivate Ge surfaces in the high-k gate module of (strained) Ge FinFET and Gate All Around devices. We use Si4H10 as Si precursor as it enables epitaxial Si growth at temperatures down to 330 degrees. C-V characteristics of blanket capacitors made on Ge virtual substrates point to the presence of an optimal Si thickness. In case of compressively strained Ge fin structures, the Si growth results in non-uniform and high strain levels in the strained Ge fin. These strain levels have been calculated for different shapes of the Ge fin and in function of the grown Si thickness. The high strain is the driving force for potential (unwanted) Ge surface reflow during Si deposition. The Ge surface reflow is strongly affected by the strength of the H-passivation during Si-capping and can be avoided by carefully selected process conditions. (C) The Author(s) 2018. Published by ECS.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical society	Place of Publication	Pennington (N.J.)	Editor
	Language		Wos	000425215200010	Publication Date	2018-01-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2162-8769; 2162-8777	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.787	Times cited	5	Open Access	OpenAccess
	Notes				Approved	Most recent IF: 1.787
	Call Number	UA @ lucian @ c:irua:149326			Serial	4933
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	Author	Dabral, A.; Pourtois, G.; Sankaran, K.; Magnus, W.; Yu, H.; de de Meux, A.J.; Lu, A.K.A.; Clima, S.; Stokbro, K.; Schaekers, M.; Collaert, N.; Horiguchi, N.; Houssa, M.
	Title	Study of the intrinsic limitations of the contact resistance of metal/semiconductor interfaces through atomistic simulations			Type	A1 Journal article
	Year	2018	Publication	ECS journal of solid state science and technology	Abbreviated Journal	Ecs J Solid State Sc
	Volume	7	Issue	6	Pages	N73-N80
	Keywords	A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this contribution, we report a fundamental study of the factors that set the contact resistivity between metals and highly doped n-type 2D and 3D semiconductors. We investigate the case of n-type doped Si contacted with amorphous TiSi combining first principles calculations with Non-Equilibrium Green functions transport simulations. The evolution of the intrinsic contact resistivity with the doping concentration is found to saturate at similar to 2 x 10(-10) Omega.cm(2) for the case of TiSi and imposes an intrinsic limit to the ultimate contact resistance achievable for n-doped Silamorphous-TiSi (aTiSi). The limit arises from the intrinsic properties of the semiconductors and of the metals such as their electron effective masses and Fermi energies. We illustrate that, in this regime, contacting heavy electron effective mass metals with semiconductor helps reducing the interface intrinsic contact resistivity. This observation seems to hold true regardless of the 3D character of the semiconductor, as illustrated for the case of three 2D semiconducting materials, namely MoS2, ZrS2 and HfS2. (C) The Author(s) 2018. Published by ECS.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical society	Place of Publication	Pennington (N.J.)	Editor
	Language		Wos	000440836000004	Publication Date	2018-05-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2162-8769; 2162-8777	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.787	Times cited	2	Open Access	Not_Open_Access
	Notes	; The authors thank the imec core CMOS program members, the European Commission, its TAKEMI5 ECSEL research project and the local authorities for their support. ;			Approved	Most recent IF: 1.787
	Call Number	UA @ lucian @ c:irua:153205UA @ admin @ c:irua:153205			Serial	5130
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	Author	Dhayalan, S.K.; Kujala, J.; Slotte, J.; Pourtois, G.; Simoen, E.; Rosseel, E.; Hikavyy, A.; Shimura, Y.; Loo, R.; Vandervorst, W.
	Title	On the evolution of strain and electrical properties in as-grown and annealed Si:P epitaxial films for source-drain stressor applications			Type	A1 Journal article
	Year	2018	Publication	ECS journal of solid state science and technology	Abbreviated Journal	Ecs J Solid State Sc
	Volume	7	Issue	5	Pages	P228-P237
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Heavily P doped Si:P epitaxial layers have gained interest in recent times as a promising source-drain stressor material for n type FinFETs (Fin Field Effect Transistors). They are touted to provide excellent conductivity as well as tensile strain. Although the as-grown layers do provide tensile strain, their conductivity exhibits an unfavorable behavior. It reduces with increasing P concentration (P > 1E21 at/cm(3)), accompanied by a saturation in the active carrier concentration. Subjecting the layers to laser annealing increases the conductivity and activates a fraction of P atoms. However, there is also a concurrent reduction in tensile strain (<1%). Literature proposes the formation of local semiconducting Si3P4 complexes to explain the observed behaviors in Si:P [Z. Ye et al., ECS Trans., 50(9) 2013, p. 1007-10111. The development of tensile strain and the saturation in active carrier is attributed to the presence of local complexes while their dispersal on annealing is attributed to strain reduction and increase in active carrier density. However, the existence of such local complexes is not proven and a fundamental void exists in understanding the structure-property correlation in Si:P films. In this respect, our work investigates the reason behind the evolution of strain and electrical properties in the as-grown and annealed Si:P epitaxial layers using ab-initio techniques and corroborate the results with physical characterization techniques. It will be shown that the strain developed in Si:P films is not due to any specific complexes while the formation of Phosphorus-vacancy complexes will be shown responsible for the carrier saturation and the increase in resistivity in the as-grown films. Interstitial/precipitate formation is suggested to be a reason for the strain loss in the annealed films. (C) The Author(s) 2018. Published by ECS.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical society	Place of Publication	Pennington (N.J.)	Editor
	Language		Wos	000440834200010	Publication Date	2018-05-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2162-8769; 2162-8777	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.787	Times cited	4	Open Access	OpenAccess
	Notes				Approved	Most recent IF: 1.787
	Call Number	UA @ lucian @ c:irua:153204			Serial	5122
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	Author	Houssa, M.; van den Broek, B.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
	Title	Theoretical study of silicene and germanene			Type	P1 Proceeding
	Year	2013	Publication	Graphene, Ge/iii-v, And Emerging Materials For Post Cmos Applications 5	Abbreviated Journal
	Volume		Issue		Pages
	Keywords	P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The structural and electronic properties of silicene and germanene on metallic and non-metallic substrates are investigated theoretically, using first-principles simulations. We first study the interaction of silicene with Ag(111) surfaces, focusing on the (4x4) silicene/Ag structure. Due to symmetry breaking in the silicene layer (nonequivalent number of top and bottom Si atoms), silicene is predicted to be semiconducting, with a computed energy gap of about 0.3 eV. However, the charge transfer occurring at the silicene/Ag(111) interface leads to an overall metallic system. We next investigate the interaction of silicene and germanene with hexagonal non-metallic substrates, namely ZnS and ZnSe. On reconstructed (semiconducting) (0001) ZnS or ZnSe surfaces, silicene and germanene are found to be semiconducting. Remarkably, the nature (indirect or direct) and magnitude of their energy band gap can be controlled by an out-of-plane electric field.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical soc inc	Place of Publication	Pennington	Editor
	Language		Wos	000354468000006	Publication Date	2013-05-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	978-1-60768-374-2; 978-1-62332-023-2	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	6	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:134451			Serial	4529
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	Author	Loo, R.; Arimura, H.; Cott, D.; Witters, L.; Pourtois, G.; Schulze, A.; Douhard, B.; Vanherle, W.; Eneman, G.; Richard, O.; Favia, P.; Mitard, J.; Mocuta, D.; Langer, R.; Collaert, N.
	Title	Epitaxial CVD growth of ultra-thin Si passivation layers on strained Ge fin structures			Type	P1 Proceeding
	Year	2017	Publication	Semiconductor Process Integration 10	Abbreviated Journal
	Volume		Issue		Pages	241-252
	Keywords	P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Epitaxially grown ultra-thin Si layers are often used to passivate Ge surfaces in the high-k gate module of (strained) Ge FinFET devices. We use Si4H10 as Si precursor as it enables epitaxial Si growth at temperatures down to 330 degrees C. C-V characteristics of blanket capacitors made on Ge virtual substrates point to the presence of an optimal Si thickness. In case of compressively strained Ge fin structures, the Si growth results in non-uniform and high strain levels in the strained Ge fin. These strain levels have been calculated for different shapes of the Ge fin and in function of the grown Si thickness. The high strain is the driving force for potential (unwanted) Ge surface reflow during the Si deposition. The Ge surface reflow is strongly affected by the strength of the H-passivation during Si-capping and can be avoided by carefully selected process conditions.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical soc inc	Place of Publication	Pennington	Editor
	Language		Wos	000426269800024	Publication Date	2017-10-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	80	Series Issue	4	Edition
	ISSN	978-1-60768-821-1; 978-1-62332-473-5	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:149965			Serial	4966
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	Author	Pourtois, G.; Dabral, A.; Sankaran, K.; Magnus, W.; Yu, H.; de de Meux, A.J.; Lu, A.K.A.; Clima, S.; Stokbro, K.; Schaekers, M.; Houssa, M.; Collaert, N.; Horiguchi, N.
	Title	Probing the intrinsic limitations of the contact resistance of metal/semiconductor interfaces through atomistic simulations			Type	P1 Proceeding
	Year	2017	Publication	Semiconductors, Dielectrics, And Metals For Nanoelectronics 15: In Memory Of Samares Kar	Abbreviated Journal
	Volume		Issue		Pages	303-311
	Keywords	P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this contribution, we report a fundamental study of the factors that set the contact resistivity between metals and highly doped semiconductors. We investigate the case of n-type doped Si contacted with amorphous TiSi combining first-principles calculations with Non-Equilibrium Green functions transport simulations. The intrinsic contact resistivity is found to saturate at similar to 2x10(-10) Omega.cm(2) with the doping concentration and sets an intrinsic limit to the ultimate contact resistance achievable for n-doped Si vertical bar amorphous-TiSi. This limit arises from the intrinsic properties of the semiconductor and of the metal such as their electron effective masses and Fermi energies. We illustrate that, in this regime, contacting metals with a heavy electron effective mass helps reducing the interface intrinsic contact resistivity.
	Address
	Corporate Author				Thesis
	Publisher	Electrochemical soc inc	Place of Publication	Pennington	Editor
	Language		Wos	000426271800028	Publication Date	2017-10-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	80	Series Issue	1	Edition
	ISSN	978-1-62332-470-4; 978-1-60768-818-1	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	1	Open Access	Not_Open_Access
	Notes	; ;			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:149966			Serial	4976
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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
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	College Park, Md	Editor
	Language		Wos	000411460400001	Publication Date	2017-09-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	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				Approved	Most recent IF: 4.808
	Call Number	UA @ lucian @ c:irua:146741			Serial	4785
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	Author	de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P.
	Title	Method to quantify the delocalization of electronic states in amorphous semiconductors and its application to assessing charge carrier mobility of p-type amorphous oxide semiconductors			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	97	Issue	4	Pages	045208
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Amorphous semiconductors are usually characterized by a low charge carrier mobility, essentially related to their lack of long-range order. The development of such material with higher charge carrier mobility is hence challenging. Part of the issue comes from the difficulty encountered by first-principles simulations to evaluate concepts such as the electron effective mass for disordered systems since the absence of periodicity induced by the disorder precludes the use of common concepts derived from condensed matter physics. In this paper, we propose a methodology based on first-principles simulations that partially solves this problem, by quantifying the degree of delocalization of a wave function and of the connectivity between the atomic sites within this electronic state. We validate the robustness of the proposed formalism on crystalline and molecular systems and extend the insights gained to disordered/amorphous InGaZnO4 and Si. We also explore the properties of p-type oxide semiconductor candidates recently reported to have a low effective mass in their crystalline phases [G. Hautier et al., Nat. Commun. 4, 2292 (2013)]. Although in their amorphous phase none of the candidates present a valence band with delocalization properties matching those found in the conduction band of amorphous InGaZnO4, three of the seven analyzed materials show some potential. The most promising candidate, K2Sn2O3, is expected to possess in its amorphous phase a slightly higher hole mobility than the electron mobility in amorphous silicon.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000423427600005	Publication Date	2018-01-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	2	Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:149318			Serial	4943
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	Author	De Clercq, M.; Moors, K.; Sankaran, K.; Pourtois, G.; Dutta, S.; Adelmann, C.; Magnus, W.; Sorée, B.
	Title	Resistivity scaling model for metals with conduction band anisotropy			Type	A1 Journal article
	Year	2018	Publication	Physical review materials	Abbreviated Journal
	Volume	2	Issue	3	Pages	033801
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	It is generally understood that the resistivity of metal thin films scales with film thickness mainly due to grain boundary and boundary surface scattering. Recently, several experiments and ab initio simulations have demonstrated the impact of crystal orientation on resistivity scaling. The crystal orientation cannot be captured by the commonly used resistivity scaling models and a qualitative understanding of its impact is currently lacking. In this work, we derive a resistivity scaling model that captures grain boundary and boundary surface scattering as well as the anisotropy of the band structure. The model is applied to Cu and Ru thin films, whose conduction bands are (quasi-) isotropic and anisotropic, respectively. After calibrating the anisotropy with ab initio simulations, the resistivity scaling models are compared to experimental resistivity data and a renormalization of the fitted grain boundary reflection coefficient can be identified for textured Ru.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	College Park, Md	Editor
	Language		Wos	000426787600001	Publication Date	2018-03-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2475-9953	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes	; The authors acknowledge the support by the Fonds National de la Recherche Luxembourg (ATTRACT Grant No. 7556175). ;			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:149866UA @ admin @ c:irua:149866			Serial	4947
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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
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	College Park, Md	Editor
	Language		Wos	000433070900003	Publication Date	2018-05-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2331-7019	ISBN		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
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	Author	Houssa, M.; Scalise, E.; Sankaran, K.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
	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	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
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	Author	Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
	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	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.
	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	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
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	Author	Clima, S.; Chen, Y.Y.; Degraeve, R.; Mees, M.; Sankaran, K.; Govoreanu, B.; Jurczak, M.; De Gendt, S.; Pourtois, G.
	Title	First-principles simulation of oxygen diffusion in HfO_x : 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	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	Clima, S.; Wouters, D.J.; Adelmann, C.; Schenk, T.; Schroeder, U.; Jurczak, M.; Pourtois, G.
	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	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	Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
	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	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.
	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	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.
	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	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	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
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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.;
	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
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