Transmission Electron Microscopy studies of the vacancy ordering in YSI2-X thin films

1991 ◽  
Vol 49 ◽  
pp. 562-563
Author(s):  
F.-R. Chen ◽  
T. L. Lee ◽  
L. J. Chen
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Thin Films ◽  
Diffraction Pattern ◽  
Annealing Temperature ◽  
Lattice Mismatch ◽  
Si Substrate ◽  
Metal Thin Films ◽  
Transmission Electron ◽  
Vacancy Ordering

YSi2-x thin films were grown by depositing the yttrium metal thin films on (111)Si substrate followed by a rapid thermal annealing (RTA) at 450 to 1100°C. The x value of the YSi2-x films ranges from 0 to 0.3. The (0001) plane of the YSi2-x films have an ideal zero lattice mismatch relative to (111)Si surface lattice. The YSi2 has the hexagonal AlB2 crystal structure. The orientation relationship with Si was determined from the diffraction pattern shown in figure 1(a) to be and . The diffraction pattern in figure 1(a) was taken from a specimen annealed at 500°C for 15 second. As the annealing temperature was increased to 600°C, superlattice diffraction spots appear at position as seen in figure 1(b) which may be due to vacancy ordering in the YSi2-x films. The ordered vacancies in YSi2-x form a mesh in Si plane suggested by a LEED experiment.

Kinetics of Vacancy Ordering in YSi2−x Thin Film on Silicon

1991 ◽  
Vol 230 ◽  
Author(s):  
T. L. Lee ◽  
L. J. Chen ◽  
F. R. Chen
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Stacking Faults ◽  
Step Structure ◽  
Transmission Electron ◽  
Vacancy Ordering ◽  
Kinetics Of

AbstractHigh resolution and conventional transmission electron microscopy have been applied to study the interfacial reaction of yttrium thin films on Si. Epitaxial Ysi2−x film was grown on (111)Si by rapid thermal annealing at 500–1000 °C. The orientation relationship between yttrium silicide and (111)Si was determined to be [0001]Ysi2−x//[111]Si and (1010)Ysi2−x//(112)Si. The vacancies in the Ysi2−x film were found to be ordered in the Si sublattice plane and form an out-of-step structure. The range of M values of the out-of-step structure was found to narrow with annealing temperature and time. Defects along specific crystallographic directions were observed and analyzed to be intrinsic stacking faults.

Microstructure of SrTiO3 Thin Films as Single Layer and Incorporated in Yba2Cu3O7-x/SrTiO3 Multilayers

1995 ◽  
Vol 401 ◽  
Author(s):  
L. Ryen ◽  
E. Olssoni ◽  
L. D. Madsen ◽  
C. N. L. Johnson ◽  
X. Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Lattice Mismatch ◽  
Single Layer ◽  
Transmission Electron ◽  
Tilt Boundaries ◽  
Interfacial Dislocations ◽  
The Individual ◽  
Film Substrate

AbstractEpitaxial single layer (001) SrTiO3 films and an epitaxial Yba2Cu3O7-x/SrTiO3 multilayer were dc and rf sputtered on (110)rhombohedral LaAIO3 substrates. The microstructure of the films was characterised using transmission electron microscopy. The single layer SrTiO3 films exhibited different columnar morphologies. The column boundaries were due to the lattice mismatch between film and substrate. The boundaries were associated with interfacial dislocations at the film/substrate interface, where the dislocations relaxed the strain in the a, b plane. The columns consisted of individual subgrains. These subgrains were misoriented with respect to each other, with different in-plane orientations and different tilts of the (001) planes. The subgrain boundaries were antiphase or tilt boundaries.The individual layers of the Yba2Cu3O7-x/SrTiO3 multilayer were relatively uniform. A distortion of the SrTiO3 unit cell of 0.9% in the ‘001’ direction and a Sr/Ti ratio of 0.62±0.04 was observed, both in correspondence with the single layer SrTiO3 films. Areas with different tilt of the (001)-planes were also present, within each individual SrTiO3 layer.

Electron Microscopy Study Of Mocvd-Grown Tio2Thin Films and Tio2/Al203 Interfaces

1990 ◽  
Vol 209 ◽  
Author(s):  
Y. Gao ◽  
K. L. Merkle ◽  
H. L. M. Chang ◽  
T. J. Zhang ◽  
D. J. Lam
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Lattice Mismatch ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Rutile Structure ◽  
Atomic Structures ◽  
Transmission Electron ◽  
Twinning Direction ◽  
Mocvd Technique

ABSTRACTTiO2 thin films grown on (1120) sapphire at 800°C by the MOCVD technique have been characterized by transmission electron microscopy. The TiO2 thin films are single crystalline and have the rutile structure. The epitaxial orientation relationship between the TiO2 thin films (R) and the substrate (S) has been foundto be: (101)[010]R║(1l20)[0001]s. Growth twins in the films are commonly observed with the twin plane{101} and twinning direction <011>. Detailed atomic structures of the twin boundaries and TiO2/α-Al203 interfaces have been investigated by highresolution electron microscopy (HREM).When the interfaces are viewed in the direction of [010]R/[000l]S, the interfaces are found to be structurally coherent in the direction of [1Ol]R/[1100]s,in which the lattice mismatch at the interfaces is about 0.5%.

Anisotropic Behaviour of Surface Roughening in Lattice Mismatched Heteroepitaxial Thin Films

1996 ◽  
Vol 436 ◽  
Author(s):  
Cengiz S. Ozkan ◽  
William D. Nix ◽  
Huajian Gao
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Lattice Mismatch ◽  
Surface Roughening ◽  
Silicon Substrates ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Annealing Experiments

AbstractHeteroepitaxial Si1-xGex. thin films deposited on silicon substrates exhibit surface roughening via surface diffusion under the effect of a compressive stress which is caused by a lattice mismatch. In these films, surface roughening can take place in the form of ridges which can be aligned along <100> or <110> directions, depending on the film thickness. In this paper, we investigate this anisotropic dependence of surface roughening and present an analysis of it. We have studied the surface roughening behaviour of 18% Ge and 22% Ge thin films subjected to controlled annealing experiments. Transmission electron microscopy and atomic force microscopy have been used to study the morphology and microstructure of the surface ridges and the dislocations that form during annealing.

scholarly journals Structural Changes in Nickel Silicide Thin Films under the Presence of Al and Ga

2010 ◽  
Vol 638-642 ◽  
pp. 2938-2943 ◽  
Author(s):  
A.V. Mogilatenko ◽  
Frank Allenstein ◽  
M.A. Schubert ◽  
Meiken Falke ◽  
G. Beddies ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Room Temperature ◽  
Structural Changes ◽  
Annealing Temperature ◽  
Nickel Silicide ◽  
Subsequent Annealing ◽  
Formation Temperature ◽  
Transmission Electron

Thin Ni/Al and Ni/Ga layers of different atomic ratios were codeposited onto Si(001) at room temperature followed by subsequent annealing. Influence of annealing temperature on morphology and composition of ternary disilicide NiSi2-xAlx and NiSi2-xGax layers was investigated by transmission electron microscopy. Addition of Al or Ga leads to a decrease of the disilicide formation temperature from 700°C down to at least 500°C. Depending on the composition closed, uniformly oriented NiSi2-xAlx and NiSi2-xGax layers were observed after annealing at 900°C, whereas reaction of a pure Ni film with Si leads to the island formation with a mixture of A- and B-type orientations.

Dislocations in SrTiO3 thin films grown on LaAlO3 substrates

2002 ◽  
Vol 17 (12) ◽  
pp. 3117-3126 ◽  
Author(s):  
Y. L. Qin ◽  
C. L. Jia ◽  
K. Urban ◽  
J. H. Hao ◽  
X. X. Xi
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Lattice Mismatch ◽  
Orthogonal Arrays ◽  
Threading Dislocations ◽  
Misfit Dislocations ◽  
Burgers Vector ◽  
Transmission Electron

The dislocation configurations in SrTiO3 thin films grown epitaxially on LaAlO3 (100) substrates were studied by conventional and high-resolution transmission electron microscopy. Misfit dislocations had, in most cases, a Burgers vector a〈100〉 and line directions of 〈100〉 These dislocations constitute orthogonal arrays of parallel dislocations at the interface, relieving the lattice mismatch between SrTiO3 and LaAlO3. Threading dislocations were found to be the major defects in the films. Two types of threading dislocations with the Burgers vectors a〈100〉?and a〈100〉?were identified. The relations of these threading dislocations with the misfit dislocations were investigated and are discussed in this paper.

Epitaxial Growth of Rare Earth Silicides on (111)Si

1993 ◽  
Vol 312 ◽  
Author(s):  
T. L. Lee ◽  
W. D. Sue ◽  
J. H. Lin ◽  
C. H. Luo ◽  
L. J. Chen
Keyword(s):  
Thin Films ◽  
Rare Earth ◽  
Diffraction Pattern ◽  
Solid Phase ◽  
Stacking Faults ◽  
Metal Thin Films ◽  
Step Structure ◽  
Displacement Vectors ◽  
Transmission Electron ◽  
Long Time

AbstractEpitaxial YSi2-x, TbSi2-x, and ErSi2-x. have been grown on (111)Si by solid phase epitaxy in ultrahigh vacuum deposited rare earth (RE) metal thin films on silicon. The evolution of vacancy ordering and defect structure in epitaxial RE silicide thin films on (111)Si have been studied by both conventional and high resolution transmission electron microscopy.Additional superlattice spots located at 1/3 <2110> in the diffraction pattern of RESi2-x, are attributed to the formation of ordered vacancy in the Si sublattice planes. The splitting of extra diffraction spots is correlated to the formation of an out-of--step structure. Streakings of the split diffraction spots in the diffraction pattern are attributed to the presence of an out-of-step structure with a range of M values. For YSi2-x and ErSi2-x, the M was found to settle down to a constant value after high temperature and/or long time annealing. For TbSi2-x, M is equal to 5 throughout the annealing.Planar defects in RESi2-x films were analyzed to be stacking faults on {1010} planes with 1/6<1213> displacement vectors. The size and density of stacking faults were found to increase and decrease, respectively, with annealing temperature and/or annealing time.

Investigation of Intermetallic Phase Formation and Structural Analysis in Annealed Al/Cu Bilayer Thin Films

2013 ◽  
Vol 845 ◽  
pp. 221-225
Author(s):  
Zulhelmi Alif Abdul Halim ◽  
Muhammad Azizi Mat Yajid ◽  
Zulkifli Mohd Rosli ◽  
Riyaz Ahmad Mohamad Ali
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Structural Analysis ◽  
Annealing Temperature ◽  
Intermetallic Phase ◽  
Intermetallic Phases ◽  
X Ray ◽  
Transmission Electron

The growth of intermetallic phases in Al/Cu bilayers thin film having 2/3 layer thickness ratios were characterized by X-ray powder diffraction (XRD), energy dispersive X-ray (EDX) and transmission electron microscopy (TEM). In annealing temperature of 200 °C, the growth is controlled by Cu diffusion which resulted to formation of θ-Al2Cu, η-AlCu, ζ-Al3Cu4 and γ-Al4Cu9 phase.

Microstructure and Current Transport Properties of YBa2Cu3O7-x/(Ba0.05, Sr0.95)TiO3 Multiple-Layer Thin Films

2003 ◽  
Vol 795 ◽  
Author(s):  
Y. Luo ◽  
R. A. Hughes ◽  
J. S. Preston ◽  
G. A. Botton
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Electrical Properties ◽  
Lattice Mismatch ◽  
Single Layer ◽  
Nanocomposite Films ◽  
Mismatch Strain ◽  
Multiple Layer ◽  
Transmission Electron

ABSTRACTYBa2Cu3O7-x (YBCO) films grown by pulsed laser deposition (PLD) on (100) LaAlO3 (LAO) substrates show a strong thickness dependence on the electrical properties. For example, for films in excess of 0.3 μm, the critical current density decreases with increasing thickness. In contrast, nano-composite films consisting of a series of multiple layers of YBa2Cu3O7-x and (Ba0.05, Sr0.95)TiO3 (BSTO) thin films having a total thickness of 5 μm show improved electrical properties. In order to understand this phenomenon, a detailed microstructural characterization has been undertaken. Transmission electron microscopy (TEM) observations show that cracks, stacking faults, c-║ crystals and secondary phase precipitates are present on the single-layer films, while a high-quality microstructure is observed for the nanocomposite multiple-layer films although defects at YBCO/BSTO interface are still present. In addition, nanocomposite films have a reduced surface roughness. In this complex microstructure, the YBCO/BSTO interfaces and the lattice mismatch strain play a crucial role in controlling the nature of the defects and stability of phases. In order to understand the role of the BSTO layer has on the microstructure, the interfacial mismatch strain and defects are analyzed by high-resolution transmission electron microscopy (HRTEM) in combination with the Moiré fringe technique.

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