The influence of strain on the diffusion of Si dimers on Si(001)

Zoethout, E.; Gürlü, O.; Zandvliet, Henricus J.W.; Poelsema, Bene

doi:10.1016/s0039-6028(00)00338-1

Cited by 24 publications

(22 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Within a simplified model of diffusion-limited growth, these strain dependencies are found to have the qualitative effect of accelerating the natural coarsening rate of larger islands, in contrast with earlier results obtained for the related InAs on GaAs system. 8 The large magnitude of the strain dependence of adatom energetics on Ge͑001͒ obtained in the present calculations also contrasts with earlier findings in other systems, 8,[10][11][12][13]23 and warrants further consideration of these effects in more detailed kinetic models to further elucidate their effect on island growth. This work was supported by the NSF under programs DMR-0102794 and NSF-MRSEC DMR-00706097, using computer resources provided by the National Partnership for Advanced Computational Infrastructure at the University of Michigan.…”

contrasting

confidence: 99%

First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

2002

View full text Add to dashboard Cite

First-principles calculations are used to calculate the strain dependencies of the binding and diffusionactivation energies for Ge adatoms on both Si͑001͒ and Ge͑001͒ surfaces. Our calculations reveal that the binding and activation energies on a strained Ge͑001͒ surface increase and decrease, respectively, by 0.21 and 0.12 eV per percent compressive strain. For a growth temperature of 600°C, these strain-dependencies give rise to a 16-fold increase in adatom density and a fivefold decrease in adatom diffusivity in the region of compressive strain surrounding a Ge island with a characteristic size of 10 nm.

show abstract

contrasting

confidence: 99%

First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

2002

View full text Add to dashboard Cite

show abstract

“…3 This underlines the high intensity of heating inside the transformed bands during high velocity impact loading of the specimens. Strain induced atomic diffusion has been severally reported in the literature [34][35][36][37][38] and has been attributed to atomic transportation by motion of dislocations. [34][35][36] In ionic crystals, atomic diffusion is induced by mobile point defects such as Schottky and Frenkel defects whose concentrations are sensitive to applied stress.…”

Section: Resultsmentioning

confidence: 97%

“…Strain induced atomic diffusion has been severally reported in the literature [34][35][36][37][38] and has been attributed to atomic transportation by motion of dislocations. [34][35][36] In ionic crystals, atomic diffusion is induced by mobile point defects such as Schottky and Frenkel defects whose concentrations are sensitive to applied stress. 37,38 In metallic alloys, impurity atom or alloying element can diffuse to the vicinity of dislocations to reduce the strain fields around them.…”

Section: Resultsmentioning

confidence: 97%

X-ray photoemission electron microscopic study of transformed shear bands in AISI 4340 steel

Ghomi

Lanke

Odeshi

2012

Canadian Metallurgical Quarterly

View full text Add to dashboard Cite

Failures of structural materials under dynamic mechanical loading at high strain rates are commonly initiated by shear strain localisation along adiabatic shear bands, which act as preferential sites for crack initiation and propagation. We have used synchrotron based X-ray photoemission electron microscopy (XPEEM) to identify chemical elements and measure compositional contrast in the shear band in AISI 4340 steel. The high spatial resolution of XPEEM combined with near edge X-ray absorption fine structure (NEXAFS) spectroscopy is used to study the microstructural evolution in transformed shear bands that formed in quench hardened and tempered AISI 4340 steel under dynamic impact loading. We compared our XPEEM findings with other complementary techniques such as energy dispersive X-ray spectroscopy and scanning electron microscopy to get a complete picture. As in the case of optical and scanning electron microscopy, XPEEM images show a featureless transformed band devoid of the martensite laths found in the parent metal. Interestingly, XPEEM images and corresponding Cr 2pR3d and Ni 2pR3d NEXAFS spectra confirms a compositional contrast in the transformed shear band that resulted in more nickel inside the shear band than in the adjacent region.Les dé faillances des maté riaux structuraux sous charge mé canique dynamique à des vitesses é levé es de dé formation sont communé ment initié es par la localisation de la dé formation de cisaillement le long des bandes de cisaillement adiabatique, lesquelles agissent comme sites pré fé rentiels pour l'amorç age et la propagation de fissure. Nous avons utilisé le synchrotron basé sur la spectromicroscopie d'é lectrons photo-excité s par rayons X (XPEEM) pour identifier les é lé ments chimiques et pour mesurer le contraste de composition dans la bande de cisaillement de l'acier AISI 4340. La haute ré solution spatiale par XPEEM, combiné e avec la spectroscopie des structures fines d'absorption X proches du seuil (NEXAFS), est utilisé e pour é tudier l'é volution de microstructure dans les bandes de cisaillement transformé es qui se forment dans l'acier AISI 4340 durci par trempe et revenu sous charge dynamique par impact. Nous avons comparé nos trouvailles par XPEEM à d'autres techniques complé mentaires comme la spectroscopie aux rayons X à dispersion d'é nergie et la microscopie é lectronique à balayage afin d'obtenir une image complè te. Comme dans le cas de la microscopie optique et é lectronique à balayage, les images XPEEM montrent une bande transformé e sans particularité et sans martensite massive trouvé e dans le mé tal parent. Ce qui est inté ressant, c'est que les images XPEEM et les spectres correspondants de NEXAFS Cr 2p R3d et Ni 2p R3d confirment un contraste de composition dans la bande de cisaillement transformé e qui a pour ré sultat la pré sence de plus de nickel à l'inté rieur de la bande de cisaillement que dans la ré gion adjacente.

show abstract

“…Although the diffusion might be anisotropic on each of the two possible reconstruction domains [22][23][24], on the scale of the ICZ that contains more than 10 2 steps, such anisotropy is averaged out and the surface appears isotropic. In contrast, the 4…”

Section: Resultsmentioning

confidence: 99%

Anisotropy of Ag Diffusion on Vicinal Si Surfaces

Sindermann

Wall

Roos

et al. 2010

e-J. Surf. Sci. Nanotechnol.

View full text Add to dashboard Cite

Photoemission electron microscopy (PEEM) is used to study Ag surface diffusion on vicinal Si surfaces. The diffusion field is represented by Iso-Coverage Zones around Ag islands during desorption. By analyzing the shape and radius of the Iso-Coverage Zone we can determine diffusion parameters. For anisotropic diffusion the zone has an elliptical shape and the aspect ratio gives a measure for the anisotropy. Using this technique, we study the degree of anisotropy of Ag diffusion on vicinal Si(001) and Si(111). With increasing miscut angles, starting from Si(001) as well as from Si (111), we find a gradually increasing anisotropy, caused by the higher step density. On higher index surfaces, like Si(119), Si(115) and Si(113), we find isotropic diffusion for surfaces with comparable dimer and (double) step structure as on Si (001)-4 • , where diffusion is strongly anisotropic.

show abstract

The influence of strain on the diffusion of Si dimers on Si(001)

Cited by 24 publications

References 28 publications

First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

X-ray photoemission electron microscopic study of transformed shear bands in AISI 4340 steel

Anisotropy of Ag Diffusion on Vicinal Si Surfaces

Contact Info

Product

Resources

About