In-Situ Regrowthi of GaAs Through Controlled Phase Transformations and Reactions of Thin Films on GaAs

ABSTRACTIn-situ depositions and reactions are utilized in the study of phase formation from solid phase reactions. We report on the formation of epitaxial GaAs and the formation of NiAs or Ni2Ga3 by the exposure of Ni3GaAs to As4 or Ga fluxes. In-situ annealing of Ni on MBE-grown GaAs leads to Ni3GaAs, and subsequent reaction with As4 or Ga drives regrowth of GaAs. The structures were analyzed by RBS, XRD, TEM, and in-situ electrical measurements.

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Структурные фазовые превращения при твердофазной реакции в тонких двухслойных пленках Al/Pt

Физика твердого тела ◽

10.21883/ftt.2018.07.46130.352 ◽

2018 ◽

Vol 60 (7) ◽

pp. 1397

Author(s):

Р.Р. Алтунин ◽

Е.Т. Моисеенко ◽

С.М. Жарков

Keyword(s):

Thin Films ◽

Electron Diffraction ◽

Phase Transformations ◽

Solid Phase ◽

Structural Phase ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Formation Heat ◽

Structural Phase Transformations

AbstractA sequence of phases forming during the solid-phase reaction in Al/Pt bilayer thin films has been investigated by in situ electron diffraction. It is shown that the amorphous PtAl_2 phase forms first during the solid-phase reaction initiated by heating. Upon further heating, PtAl_2, Pt_2Al_3, PtAl, and Pt_3Al crystalline phases sequentially form, which is qualitatively consistent with an effective formation heat model. The content of phases forming during the reaction has been quantitatively analyzed and the structural phase transformations have been examined.

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ChemInform Abstract: Solid-Phase Reactions in Thin Films: in situ HREM and Associated Techniques

ChemInform ◽

10.1002/chin.199914306 ◽

2010 ◽

Vol 30 (14) ◽

pp. no-no

Author(s):

Robert Sinclair

Keyword(s):

Thin Films ◽

Solid Phase ◽

Solid Phase Reactions

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The use of transmission and analytical electron microscopy in studying reactions and phase transformations in thin film

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150046 ◽

1993 ◽

Vol 51 ◽

pp. 842-843

Author(s):

K. Barmak

Keyword(s):

Thin Film ◽

Thin Films ◽

Phase Transformations ◽

Analytical Electron Microscopy ◽

Ex Situ ◽

Multilayer Thin Films ◽

Absolute Concentration ◽

Analytical Electron ◽

Deposition Step

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.

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