The equilibrium crystal shape of nickel

Meltzman, Hila; Chatain, Dominique; Avizemer, Dan; Besmann, Theodore M.; Kaplan, Wayne D.

doi:10.1016/j.actamat.2011.02.021

Cited by 65 publications

(46 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This observation is in good agreement with previous results reported in the literature [21,38,39]. Recently Meltzman and co-workers [40] have shown that {1 0 0} facets are evident for the equilibrium shape of Ni nanoparticles while {2 1 1} facets are absent. The film was only annealed for a relatively short period of time during the in situ TEM experiments, and the presence of the {2 1 1} facets therefore suggest that the corresponding nickel islands have not yet fully reached thermodynamic equilibrium.…”

Section: In Situ Annealingsupporting

confidence: 83%

“…The film was only annealed for a relatively short period of time during the in situ TEM experiments, and the presence of the {2 1 1} facets therefore suggest that the corresponding nickel islands have not yet fully reached thermodynamic equilibrium. However, the thickness of the TEM sample and the presence of NiO on the surface of the metal film may cause a change in the equilibrium shape of the Ni islands [40]. The dispersed Ni islands for the annealed 5 nm film show rounded edges, with no facet formation.…”

Section: In Situ Annealingmentioning

confidence: 99%

See 1 more Smart Citation

Structural changes during the reaction of Ni thin films with (100) silicon substrates

et al. 2012

View full text Add to dashboard Cite

Ultrathin films of nickel deposited onto (1 0 0) Si substrates were found to form kinetically constrained multilayered interface structures characterized by structural and compositional gradients. The presence of a native SiO 2 on the substrate surface in tandem with thickness-dependent intrinsic stress of the metal film limits the solid-state reaction between Ni and Si. A roughly 6.5 nm thick Ni film on top of the native oxide was observed regardless of the initial nominal film thickness of either 5 or 15 nm. The thickness of the silicide layer that formed by Ni diffusion into the Si substrate, however, scales with the nominal film thickness. Cross-sectional in situ annealing experiments in the transmission electron microscope elucidate the kinetics of interface transformation towards thermodynamic equilibrium. Two competing mechanisms are active during thermal annealing: thermally activated diffusion of Ni through the native oxide layer and subsequent transformation of the observed compositional gradient into a thick reaction layer of NiSi 2 with an epitaxial orientation relationship to the Si substrate; and, secondly, metal film dispersion and subsequent formation of faceted Ni islands on top of the native oxide layer.

show abstract

Section: In Situ Annealingsupporting

confidence: 83%

Section: In Situ Annealingmentioning

confidence: 99%

Structural changes during the reaction of Ni thin films with (100) silicon substrates

et al. 2012

View full text Add to dashboard Cite

show abstract

“…By far 15 the best experimental approach consists of analysis of carefully equilibrated crystallites [1,2,3]. Such process is viable on some materials but not the others, and can be questionable in reproducibility.…”

Section: Introductionmentioning

confidence: 99%

Surface energy and its anisotropy of hexagonal close-packed metals

Luo

Qin

2014

Surface Science

View full text Add to dashboard Cite

The absolute unrelaxed surface energy and its full orientation-dependent behaviour of 13 HCP metals are studied via a broken-bond base geometric model. The model is integrated with the Rose-Vinet universal potential to investigate arbitrary orientations which are not assessable by other methods. Using only three materials constants, the calculated results show only marginal discrepancies with reported experimental values, except for divalent sp metals Mg, Zn and Cd where the calculated values are lower by a factor of 2. Stereographic projections of all 13 metals show global minimum on (0001) pole with an overall anisotropy of 15% to 21%. The equilibrium crystal shape of HCP is found to be truncated hexagonal bi-prismatic, with (0001) always favoured but the bi-prismatic facets vary from one metal to another. All projection patterns show strong six-fold symmetries but are unique for every element. The patterns are found to be largely determined by an anharmonicity factor η. Best agreement with experimental findings are found for Be, Sc, Ti,Y, Zr and Hf which possess comparatively low η. We believe the stereographic projections of these elements are the more representative for HCP metals.

show abstract

“…In contrast to the large technological importance of this system, Ni-alumina interfaces were not experimentally studied to the same extent as other metalalumina interfaces. This is perhaps due to the relatively high melting temperature and/or because of the relatively large surface energy of Ni, which requires an extremely pure environment for model studies [8][9].Given the importance of the Ni-Al 2 O 3 system, and the questions raised by numerous atomistic simulations of this system, the goal of the present work is to determine the structure and energy of Ni equilibrated in contact with (0001) sapphire. Samples are based on very pure thin Ni films which were dewetted in the solid-state (and under controlled impurity levels and oxygen partial pressure) to reach equilibrium, from which both the interface structure and energy can be determined.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

Structure and Energy of Equilibrated Ni-Al₂O₃ Interfaces

Meltzman

Kaplan

2011

Microsc Microanal

View full text Add to dashboard Cite

The structure, chemistry and properties of metal-ceramic interfaces have been the focus of many research studies, largely due to potential technological applications [1]. At the same time, the thermodynamic properties of metal-ceramic interfaces are of fundamental importance, defining equilibrium segregation and the thermodynamic work of adhesion. For the most part, solid-liquid interfacial energies for metal-ceramic systems have been studied, while it is clear that it is the solidsolid interfacial energy which is important for most applications. The complexity of the solid-solid interface structure, together with the experimental challenge of measuring solid-solid interfacial energy often inhibits quantitative treatments of interfacial phenomenon.One of the most studied types of metal-ceramic interfaces is that between FCC metals and -Al 2 O 3 (sapphire). These interfaces are usually produced either by diffusion bonding of a pre-determined orientation [2], or by thin film deposition such as molecular beam epitaxy (MBE) [3]. It should be noted that these preparation techniques do not necessarily produce equilibrated interfaces. The asbonded or as-deposited interface states often reflect a metastable interface structure and orientation, rather than a thermodynamically equilibrated state. The question of whether the examined interface is equilibrated or not, and whether it reflects the minimum energy configuration of the interface is rarely addressed, although this is a significant driving force for microstructural evolution of interfaces.One way to equilibrate metal-ceramic interfaces is to dewet thin metallic films on ceramic substrates, which is essentially a disruption of the film driven by the minimization of surface and interfacial energy [4][5][6]. This process of film agglomeration results in a very large number of isolated particles, which can be investigated separately to achieve very good statistics (Fig. 1). Transmission electron microscopy (TEM) samples can be prepared with a quality good enough for atomistic structure analysis [7], and from the shape of the particles TEM data can provide the means to determine the solid-solid interface energy [4].In addition to being a good metal-ceramic model system, Ni-alumina interfaces can be found in numerous technological applications. In contrast to the large technological importance of this system, Ni-alumina interfaces were not experimentally studied to the same extent as other metalalumina interfaces. This is perhaps due to the relatively high melting temperature and/or because of the relatively large surface energy of Ni, which requires an extremely pure environment for model studies [8][9].Given the importance of the Ni-Al 2 O 3 system, and the questions raised by numerous atomistic simulations of this system, the goal of the present work is to determine the structure and energy of Ni equilibrated in contact with (0001) sapphire. Samples are based on very pure thin Ni films which were dewetted in the solid-state (and under controlled impurity levels and o...

show abstract

The equilibrium crystal shape of nickel

Cited by 65 publications

References 34 publications

Structural changes during the reaction of Ni thin films with (100) silicon substrates

Structural changes during the reaction of Ni thin films with (100) silicon substrates

Surface energy and its anisotropy of hexagonal close-packed metals

Structure and Energy of Equilibrated Ni-Al₂O₃ Interfaces

Contact Info

Product

Resources

About

The equilibrium crystal shape of nickel

Cited by 65 publications

References 34 publications

Structural changes during the reaction of Ni thin films with (100) silicon substrates

Structural changes during the reaction of Ni thin films with (100) silicon substrates

Surface energy and its anisotropy of hexagonal close-packed metals

Structure and Energy of Equilibrated Ni-Al2O3 Interfaces

Contact Info

Product

Resources

About

Structure and Energy of Equilibrated Ni-Al₂O₃ Interfaces