Surfactant-Mediated Growth of MnSi1.7 on Si(001)

AbstractThe formation of the silicide MnSi1.7 by reactive deposition of Mn onto Si(001) has been studied using Sb as a surfactant. The growth was performed under UHV conditions by simultaneous or consecutive exposure of the Si substrates, held at high temperatures (550°C, 600 °C), to a flux of Sb and Mn atoms. The presence of Sb during the growth strongly increases the island density and changes the crystalline orientation of the MnSi1.7 grains. The morphology and the orientation of the resulting silicide are the same both for the deposition of Mn on a Sb terminated Si(001) surface and for the co-deposition of Mn and Sb on Si(001). A residual Sb coverage close to one monolayer (ML) at the sample surface has been determined for both of the preparation modes at Tsub = 550 °C. The transition from the growth mode without Sb to the surfactant-controlled growth has been studied for Tsub = 600 °C. It has been found that the silicide morphology and orientation strongly depend on the thickness of Sb pre-coverage, which was increased from 0 to about 0.7 ML (1 ML = 6.78·1014 atoms cm-2).

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Effects of Heating Rate on Formation of Globular and Acicular Austenite during Reversion from Martensite

Metals ◽

10.3390/met9020266 ◽

2019 ◽

Vol 9 (2) ◽

pp. 266 ◽

Cited By ~ 3

Author(s):

Xianguang Zhang ◽

Goro Miyamoto ◽

Yuki Toji ◽

Tadashi Furuhara

Keyword(s):

Heating Rate ◽

High Temperatures ◽

The Other ◽

Growth Mode ◽

High Heating Rate ◽

Heating Rates ◽

Other Hand ◽

High Heating ◽

Martensite Matrix

The effects of heating rate on the formation of acicular and globular austenite during reversion from martensite in Fe–2Mn–1.5Si–0.3C alloy have been investigated. It was found that a low heating rate enhanced the formation of acicular austenite, while a high heating rate favored the formation of globular austenite. The growth of acicular γ was accompanied by the partitioning of Mn and Si, while the growth of globular γ was partitionless. DICTRA simulation revealed that there was a transition in growth mode from partitioning to partitionless for the globular austenite with an increase in temperature at high heating rate. High heating rates promoted a reversion that occurred at high temperatures, which made the partitionless growth of globular austenite occur more easily. On the other hand, the severer Mn enrichment into austenite at low heating rate caused Mn depletion in the martensite matrix, which decelerated the reversion kinetics in the later stage and suppressed the formation of globular austenite.

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CoSi and CoSi2 Phase Formation on Bulk and Soi Si Substrates

MRS Proceedings ◽

10.1557/proc-320-373 ◽

1993 ◽

Vol 320 ◽

Cited By ~ 3

Author(s):

S. L. Hsia ◽

T. Y. Tan ◽

P. L. Smith ◽

G. E. Mcguire

Keyword(s):

Free Energy ◽

Energy Release ◽

Gibbs Free Energy ◽

High Temperatures ◽

Phase Formation ◽

Energy Reduction ◽

Formation Temperature ◽

Si Substrates ◽

Two Phases ◽

Source Materials

ABSTRACTWe have studied the CoSi and CoSi2 phase formation sequence in (001) bulk and SOI Si wafers, using Co/Ti bimetallic layers as source materials which are suitable for growing epitaxial CoSi2 films on (001) Si. In bulk Si, co-formation of polycrystalline CoSi and epitaxial CoSi2 phases at T>500°C have been observed. These phases form respectively at the metal and Si sides of the film. For very long times and/or at high temperatures, only epitaxial CoSi2 is observed, e.g., for samples annealed at 560°C for 30 min or at 900°C for 10 s. When using (001) SOI Si with inexhaustible Co supply, only polycrystalline CoSi has been formed for a 900°C 10 s annealing, which is in contrast to the bulk Si results. This phenomenon is understood on the basis of Gibbs free energy reduction in forming the two phases. In the CoSi2 formation temperature range, Gibbs free energy release in forming CoSi2 is only ∼10% more than that of forming CoSi. Consequently, after all Si atoms have been consumed, the formation of CoSi becomes energetically more favorable, since the free energy reduction due to formation of 2x mole of CoSi is much larger than that due to formation of lx mole of CoSi2, where x is the SOI Si mole number.

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Possible burst-like facet growth mode at high temperatures

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2008.04.030 ◽

2008 ◽

Vol 310 (14) ◽

pp. 3391-3397 ◽

Cited By ~ 1

Author(s):

Davorin Lovrić ◽

Zlatko Vučić ◽

Jadranko Gladić

Keyword(s):

High Temperatures ◽

Growth Mode ◽

Facet Growth

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Влияние состава зародышевого слоя AlGaAs на формирование антифазных доменов в структурах (Al)GaAs, выращенных газофазной эпитаксией на подложках Ge/Si(100)

Письма в журнал технической физики ◽

10.21883/pjtf.2021.08.50852.18670 ◽

2021 ◽

Vol 47 (8) ◽

pp. 37

Author(s):

А.В. Рыков ◽

Р.Н. Крюков ◽

И.В. Самарцев ◽

П.А. Юнин ◽

В.Г. Шенгуров ◽

...

Keyword(s):

Solid Solution ◽

Optical Properties ◽

Seed Layer ◽

Aluminum Content ◽

Sample Surface ◽

Gaas Layer ◽

Solution Composition ◽

Solid Solution Composition ◽

Si Substrates ◽

Antiphase Domains

GaAs-based heterostructures grown by metalorganic vapor-phase epitaxy on virtual Ge/Si substrates using an AlxGa1-xAs seed layer with different aluminum content x in the solid solution are investigated. The effect of solid solution composition on the density and size of antiphase domains emerging on the sample surface and on the optical properties of the GaAs layer is shown. Si(100) substrates with a small unintentional miscut of 0.7° to [110] were used for growth.

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Initial growth mode of ultra-thin Al films on a W(110) surface at high temperatures

Applied Science and Convergence Technology ◽

10.5757/asct.2015.24.6.228 ◽

2015 ◽

Vol 24 (6) ◽

pp. 228-231

Author(s):

Dae Sun Choi ◽

Mi Mi Park

Keyword(s):

High Temperatures ◽

Growth Mode ◽

Initial Growth

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Microstructural Identification of SiNx Films by Real-Time Ellipsometry

MRS Proceedings ◽

10.1557/proc-472-349 ◽

1997 ◽

Vol 472 ◽

Author(s):

G. Soto ◽

E. C. Samano ◽

R. Machorro ◽

M. Avalos ◽

L. Cota

Keyword(s):

Real Time ◽

Film Growth ◽

Incidence Angle ◽

Polarization State ◽

Sample Surface ◽

Deposition Process ◽

Slight Variation ◽

Si Substrates ◽

Amorphous Si

ABSTRACTReal-time ellipsometry has shown to be a powerful tool to analyze thin films during processing. It is non-disturbing and its sensitivity lies in the submonolayer range. In fact, a slight variation in the film microstructure might result in a significant change of the polarization state of the reflected beam from the sample surface. SiNx layers have been grown on glass, quartz, KC1 and Si substrates by laser ablating a Si3N4 sintered target in vacuum and N2 environment. The film growth was monitored by real time ellipsometry at a fixed wavelength, and a fixed incidence angle. Once the deposition process is completed, the refractive index was obtained by perfoming in situ spectroellipsometric measurements in the 1.5 to 5 eV photon-energy range. The best curve fitting of the experimental data is used to find the film composition: a mixture of Si3N4, polycrystalline Si, and amorphous Si. The films composition and micro structure inferred from ellipsometric data are compared to those obtained by in-situ surface techniques and TEM, respectively.

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X-ray investigation of polytype distribution in InAs nanowires during MBE growth

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314092511 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C748-C748

Author(s):

Ullrich Pietsch ◽

Andreas Biermanns ◽

Emmanouil Dimakis ◽

Lutz Geelhaar ◽

Anton Davydok ◽

...

Keyword(s):

Time Evolution ◽

Stacking Faults ◽

Growth Conditions ◽

Growth Mode ◽

Ex Situ ◽

Growth Time ◽

X Ray Diffraction ◽

X Ray ◽

Si Substrates ◽

Liquid Indium

The monolithic integration of III-V semiconductors with Si is the ideal way to combine the superior optoelectronic properties of the compound semiconductors with the mature Si technology. This integration can be realized by growing epitaxially dislocation-free III-V NWs on Si substrates either in the vapor-liquid-solid (VLS) or in the vapor-solid (VS) mode associated with the presence or absence, respectively, of group-III liquid droplets on the NW tips [1]. In this work, we investigate the correlation between the growth mode and the forming polytypes in InAs NWs grown on Si(111). The growth was performed in the molecular beam epitaxy chamber of beamline 11XU at Spring8 [2], while the structural dynamics was probed by in situ x-ray diffraction. Specifically, the time evolution of the formation of wurtzite (WZ) and zincblende (ZB) polytypes was monitored during the NW growth. Despite the As-rich growth conditions, a spontaneous build-up of liquid In on Si was found to be present in the nucleation phase, where the InAs nuclei mainly grow in the WZ phase with low number of stacking faults. Shortly after the nucleation, the liquid In is consumed by the excessive As, and the growth continues in the VS mode with an increasing density of stacking faults forming in the NW crystal. The time evolution of the liquid Indium signal (Fig. (a)) correlates well with the time evolution of wurzite growth rate (Fig (b)). The latter saturates at a time where the liquid indium disappers, i.e. where the VLS changes into the VS mode, whereas the zinc-blende polytypes grow almost continuous in both VLS and VS growth mode. The dynamics of stacking faults density was determined quantitatively by ex-situ X-ray diffraction measuring thestacking fault induced increase of the peak width of wurtzite reflections at InAs nanowire samples of different length ; i.e. growth time [3].

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Excimer Laser Photofragmentation of TMA on Aluminum: Identification of Photoproduct Desorption Dynamics

MRS Proceedings ◽

10.1557/proc-131-369 ◽

1988 ◽

Vol 131 ◽

Author(s):

T. E. Orlowski ◽

D. A. Mantell

Keyword(s):

Gas Phase ◽

Excimer Laser ◽

Direct Evidence ◽

Hydrogen Abstraction ◽

Sample Surface ◽

Translational Energy ◽

Quadrupole Mass ◽

Gas Phase Reactions ◽

Si Substrates ◽

Site Binding

ABSTRACTNew mechanistic details regarding aluminum deposition by ArF excimer laser photodecomposition of trimethylaluminum (TMA) adsorbed on aluminum covered SiO 2/Si substrates have been obtained using a time-of-flight quadrupole mass spectrometer. CH3 radicals and Al-(CH3)n (n = 1,2,3) species are efficiently photoejected from the surface with up to 0.22 eV of translational energy. Experiments at various TMA dosing levels reveal differences in desorbed fragment translational energy presumably associated with variations in surface site binding energy. No direct evidence is found for desorption of A1 from the surface indicating that A1 is more tightly bound than methyl-aluminum fragments. By carefully monitoring changes in fragment translational energy as an A1 deposit forms on the clean SiO2/Si substrate, we examine how the surface influences the onset of A1 growth. No evidence of ethane or methane desorption from the sample surface is found implying that radical recombination and hydrogen abstraction are primarily secondary gas phase reactions which are not surface initiated.

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