In situ controlled reactions and phase formation of thin films on GaAs

1998 ◽  
Vol 16 (4) ◽  
pp. 2280 ◽  
Author(s):  
D. A. Caldwell
Keyword(s):  
Thin Films ◽  
Phase Formation

Monitoring the Phase Formation of Coevaporated Lead Halide Perovskite Thin Films by in Situ X-ray Diffraction

2014 ◽  
Vol 5 (19) ◽  
pp. 3308-3312 ◽  
Author(s):  
Paul Pistor ◽  
Juliane Borchert ◽  
Wolfgang Fränzel ◽  
René Csuk ◽  
Roland Scheer
Keyword(s):  
Thin Films ◽  
Phase Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Halide Perovskite ◽  
Lead Halide

In-situ investigation of the icosahedral Al–Cu–Fe phase formation in thin films

2012 ◽  
Vol 534 ◽  
pp. 47-51 ◽  
Author(s):  
F. Haidara ◽  
B. Duployer ◽  
D. Mangelinck ◽  
M.-C. Record
Keyword(s):  
Thin Films ◽  
Phase Formation ◽  
In Situ Investigation

In situ Sputter Deposition of PbTiO3 Thin Films on Different Substrates: Influence of the Growth Temperature and the Sputtered Lead Flux on the Perovskite Phase Formation

1997 ◽  
Vol 12 (4) ◽  
pp. 997-1007 ◽  
Author(s):  
B. Jaber ◽  
D. Rèmiens ◽  
B. Thierry
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Substrate Temperature ◽  
Phase Formation ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Sputter Deposition ◽  
Lead Content ◽  
Substrate Nature

Thin films of lead titanate were prepared in situ using radio-frequency magnetron sputter deposition. The in situ perovskite phase formation has been studied as a function of the substrate temperature, the sputtered lead flux, and the substrate nature. The incident lead flux is controlled by the lead content in the target. An equilibrium zone, i.e., a saturation effect of the lead incorporation, exists where the films are stoichiometric. The temperature at which this zone appears depends on the sputtered lead flux and the substrate type. The growth mechanism is governed by a competition between the arrival rate of Pb and their re-evaporation from the film during the growth. The in situ formation temperature of the perovskite phase increased when the incident Pb flux increased. As a result, PbTiO3 films have been prepared at low temperature with appropriate combination of the substrate temperature and the lead content in the target, i.e., the sputtered lead flux. Since the lead sticking coefficient is very sensitive to the substrate material, the perovskite phase appears at different temperatures, depending on the substrate nature. PbTiO3 films are obtained at 550 °C on Al2O3 and SrTiO3 substrates; on Si/SiO2/Ti/Pt substrates, stoichiometric films are obtained at 440 °C. The structure and the microstructure of the films were examined at various deposition conditions. The substrate temperature strongly influenced the film orientation, and the crystallinity depended on the incident lead flux. High quality thin films (FWHM = 0.2°) are obtained at 550 °C on SrTiO3 substrates. The films deposited at 440 °C on Si/SiO2Ti/Pt show ferroelectric properties. This self-controlling mechanism of the stoichiometric composition allows the growth of ferroelectric films at low temperature, compatible with semi-conductor technologies for the realization of integrated circuits

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

1998 ◽  
Vol 514 ◽  
Author(s):  
D. A. Caldwell ◽  
L.-C. Chen ◽  
A. H. Bensaoula ◽  
J. K. Farrer ◽  
C. B. Carter ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Transformations ◽  
Phase Formation ◽  
Solid Phase ◽  
Electrical Measurements ◽  
Subsequent Reaction ◽  
Epitaxial Gaas ◽  
Solid Phase Reactions

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.

Nucleation and Early Growth of Sputtered thin Films

1970 ◽  
Vol 28 ◽  
pp. 516-517
Author(s):  
Dudley M. Sherman ◽  
Thos. E. Hutchinson
Keyword(s):  
Thin Films ◽  
Electron Beam ◽  
Ion Beam ◽  
Ion Source ◽  
Water Cooling ◽  
Stages Of Growth ◽  
Lens Assembly ◽  
Microscope Technique ◽  
Ion Beam Sputter Deposition

The in situ electron microscope technique has been shown to be a powerful method for investigating the nucleation and growth of thin films formed by vacuum vapor deposition. The nucleation and early stages of growth of metal deposits formed by ion beam sputter-deposition are now being studied by the in situ technique.A duoplasmatron ion source and lens assembly has been attached to one side of the universal chamber of an RCA EMU-4 microscope and a sputtering target inserted into the chamber from the opposite side. The material to be deposited, in disc form, is bonded to the end of an electrically isolated copper rod that has provisions for target water cooling. The ion beam is normal to the microscope electron beam and the target is placed adjacent to the electron beam above the specimen hot stage, as shown in Figure 1.

Epitaxy and texture analysis of Bi-Sr-Ca-Cu-O thin films on (100) MgO using Transmission Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 68-69
Author(s):  
J. T. Sizemore ◽  
D. G. Schlom ◽  
Z. J. Chen ◽  
J. N. Eckstein ◽  
I. Bozovic ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Critical Currents ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Cell Axis ◽  
Transmission Electron ◽  
Synthesis Procedure

Investigators observe large critical currents for superconducting thin films deposited epitaxially on single crystal substrates. The orientation of these films is often characterized by specifying the unit cell axis that is perpendicular to the substrate. This omits specifying the orientation of the other unit cell axes and grain boundary angles between grains of the thin film. Misorientation between grains of YBa2Cu3O7−δ decreases the critical current, even in those films that are c axis oriented. We presume that these results are similar for bismuth based superconductors and report the epitaxial orientations and textures observed in such films.Thin films of nominally Bi2Sr2CaCu2Ox were deposited on MgO using molecular beam epitaxy (MBE). These films were in situ grown (during growth oxygen was incorporated and the films were not oxygen post-annealed) and shuttering was used to encourage c axis growth. Other papers report the details of the synthesis procedure. The films were characterized using x-ray diffraction (XRD) and transmission electron microscopy (TEM).

Characterization of reactive phase formation in sputter-deposited Ni/Al multilayer thin films using TEM

1996 ◽  
Vol 54 ◽  
pp. 1000-1001
Author(s):  
G. Lucadamo ◽  
K. Barmak ◽  
C. Michaelsen
Keyword(s):  
Thin Films ◽  
Phase Formation ◽  
Dark Field ◽  
Nickel Layer ◽  
Multilayer Thin Films ◽  
Cross Sectional ◽  
Dark Field Imaging ◽  
Transmission Electron ◽  
Sputter Deposited ◽  
Constant Heating

The subject of reactive phase formation in multilayer thin films of varying periodicity has stimulated much research over the past few years. Recent studies have sought to understand the reactions that occur during the annealing of Ni/Al multilayers. Dark field imaging from transmission electron microscopy (TEM) studies in conjunction with in situ x-ray diffraction measurements, and calorimetry experiments (isothermal and constant heating rate), have yielded new insights into the sequence of phases that occur during annealing and the evolution of their microstructure.In this paper we report on reactive phase formation in sputter-deposited lNi:3Al multilayer thin films with a periodicity A (the combined thickness of an aluminum and nickel layer) from 2.5 to 320 nm. A cross-sectional TEM micrograph of an as-deposited film with a periodicity of 10 nm is shown in figure 1. This image shows diffraction contrast from the Ni grains and occasionally from the Al grains in their respective layers.

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

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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