Lattice and atomic structure imaging of semiconductors by high resolution transmission electron microscopy

AbstractThe atomic structure of representative tilt boundaries in gold has been determined by high resolution transmission electron microscopy. Characteristic and varying regions of decreased density and coordination have been identified and related to mechanisms of grain boundary diffusion and migration

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Characterization of the Structure and Polarity of Twin Boundaries in GaP

MRS Proceedings ◽

10.1557/proc-510-613 ◽

1998 ◽

Vol 510 ◽

Author(s):

Dov Cohent ◽

D.L. Medlin ◽

C. Barry Carter

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Twin Boundary ◽

Atomic Structure ◽

Twin Boundaries ◽

Planar Defects ◽

Transmission Electron ◽

Crystallographic Planes

AbstractThe structure of planar defects in GaP films grown by MBE on Si (110) was investigated by transmission electron microscopy. Growth of GaP films on the (110) surface produced numerous microtwins which formed both first and second order twin boundaries. Using high-resolution transmission electron microscopy, the atomic structure of Σ=3 and Σ=9 twin boundaries were studied. Both the Σ=3 and Σ=9 interfaces were observed to facet along specific crystallographic planes. Geometric models of the Σ=9 {221} twin boundary accounting for different polar bonding configurations were proposed and compared with experimental observations.

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Structure of Low- And High-Angle Grain Boundaries In YBCO/MgO Films

Microscopy and Microanalysis ◽

10.1017/s1431927600023503 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 676-677

Author(s):

S. Oktyabrsky ◽

R. Kalyanaraman ◽

K. Jagannadham ◽

J. Narayan

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Grain Boundaries ◽

Atomic Structure ◽

Boundary Plane ◽

Dislocation Model ◽

High Angle ◽

Transmission Electron

Grain boundaries (GBs) in laser deposited YB2Cu3O7-δ/MgO(001) thin films have been investigated by high-resolution transmission electron microscopy (TEM) and scanning TEM (STEM). We report both statistics and atomic structure of low-angle and high-angle [001] tilt grain boundaries resulting from almost perfect c-axis textured YBCO films.Atomic structure of low-angle GBs was analyzed using a dislocation model. These boundaries have been found to be aligned primarily along (100) and (110) interface planes. For (100) boundary plane, the GB consists of a periodic array of [100] dislocations (Fig.l). For (110) boundary plane, the array is also periodic but every [110] dislocation is split by ∼ 1.5 nm into two [100] and [010] dislocations (Fig.2). We have calculated energy of various configurations and shown that the energy of the (110) boundary with dissociated dislocations is comparable to that of (100) boundary, which explains the coexistence of (100) and (110) interface facets along the boundary.

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Atomic Structure OF YΣ=5 (130) Symmetrical Tilt Boundary In Strontium Titanate

MRS Proceedings ◽

10.1557/proc-295-115 ◽

1992 ◽

Vol 295 ◽

Cited By ~ 1

Author(s):

V. Ravikumar ◽

Vinayak P. Dravid

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Grain Boundary ◽

Strontium Titanate ◽

Atomic Structure ◽

Coincidence Site Lattice ◽

Tilt Boundary ◽

Transmission Electron ◽

Resolution Electron

AbstractThe atomic structure of a pristine (undoped) boundary in strontium titanate has been investigated using transmission electron microscopy techniques. Results of electron diffraction studies indicate a pure tilt boundary with a common \001] tilt axis, and a tilt angle of 36.8°, which corresponds to a Σ-= 5 grain boundary in the Coincidence Site Lattice (CSL) notation. High Resolution Transmission Electron Microscopy (HRTEM) indicates a symmetric tilt grain boundary with a (130) type grain boundary plane. No cation non-stoichiometry or impurity segregants could be detected at the interface, within the limits of the Energy Dispersive X-ray microanalysis technique used. The grain boundary has a compact core, with negligible planenormal rigid body translation (RBT). An in-plane RBT of (1/2)d130 (˜ 0.62 A°) was identified from the high resolution electron micrographs. An empirical model of the relaxed atomic structure of the grain boundary is proposed.

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