Structural Characterization of Epitaxial GMR Magnetic Multilayers and Spin Valves Grown by Sputter Deposition

2000 ◽  
Vol 614 ◽  
Author(s):  
H. Geng ◽  
R. Loloee ◽  
J.W. Heckman ◽  
J. Bass ◽  
W.P. Pratt ◽  
...  
Keyword(s):  
High Resolution ◽  
Epitaxial Growth ◽  
Magnetic Multilayers ◽  
Sputter Deposition ◽  
Dc Magnetron Sputtering ◽  
Cu Films ◽  
Electron Backscatter ◽  
High Resolution Tem ◽  
Fcc Structure

ABSTRACTEpitaxial Cu/Py/FeMn and (Cu/Co)×20 GMR magnetic multilayers were grown on single crystal (011) Nb that was deposited on (1121) Al2O3 substrates by dc magnetron sputtering. Electron backscatter patterns (EBSPs) revealed that the Cu films display two twin variants, corresponding to two stacking sequences of {111} planes in fcc. The epitaxial orientation relationship between the bcc Nb and both fcc Cu variants was the Nishiyama-Wasserman (N-W) relationship. Conventional TEM observations revealed epitaxial growth for both the Cu/Py/FeMn and (Cu/Co)×20 multilayers. High-resolution TEM confirmed epitaxial growth of close packed (011) Nb on (1120) Al2O3 substrates with [111]Nb∥[0001]Al2O3. Numerous small twins were observed in the Cu near the Cu-Nb interface of the Cu/Py/FeMn multilayer. In the Cu/Co multilayer, the growth planes of the Cu and Co were found to be {100} instead of the expected close-packed {111} planes of the fcc structure.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

scholarly journals Common Phase and Structure Misidentifications in High-Resolution TEM Characterization of Perovskite Materials

2020 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Yu-Hao Deng
Keyword(s):  
High Resolution ◽  
Research Field ◽  
Structure Characterization ◽  
Phase Identification ◽  
Lead Iodide ◽  
Perovskite Materials ◽  
High Resolution Tem ◽  
Methylammonium Lead Iodide ◽  
Dose Imaging

High-resolution TEM (HRTEM) is a powerful tool for structure characterization. However, methylammonium lead iodide (MAPbI3) perovskite is highly sensitive to electron beams and easily decomposes into lead iodide (PbI2). Misidentifications, such as PbI2 being incorrectly labeled as perovskite, are widely present in HRTEM characterization and would negatively affect the development of perovskite research field. Here misidentifications in MAPbI3 perovskite are summarized, classified, and corrected based on low-dose imaging and electron diffraction (ED) simulations. Corresponding crystallographic parameters of intrinsic tetragonal MAPbI3 and the confusable hexagonal PbI2 are presented unambiguously. Finally, the method of proper phase identification and some strategies to control the radiation damage in HRTEM are provided. This warning paves the way to avoid future misinterpretations in HRTEM characterization of perovskite and other electron beam-sensitive materials.

Epitaxial Growth of TiN on GaAs(100) by Pulsed Laser Deposition

1992 ◽  
Vol 285 ◽  
Author(s):  
Tsvetanka S. Zheleva ◽  
K. Jagannadham ◽  
A. Kumar ◽  
J. Narayan
Keyword(s):  
High Resolution ◽  
Pulsed Laser Deposition ◽  
Epitaxial Growth ◽  
Film Growth ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Epitaxial Relationship ◽  
Cross Sectional ◽  
Tin Films ◽  
High Resolution Tem

ABSTRACTEpitaxial growth of TiN films on GaAs(100) by pulsed laser deposition has been studied. Excimer KrF laser (λ=248 nm, τ=30 ns) has been used for deposition of TiN films in a chamber maintained at vacuum of ≤ 10−6 torr. The microstructure of TiN films has been characterized by x-ray diffraction and transmission electron microscopy (TEM). Cross-sectional high resolution TEM showed a smooth unreacted interface between the single crystalline TiN film and GaAs. The predominant epitaxial relationship was found to be [110]TiN//[010]GaAs, (220)TiN//(040)GaAs at a substrate temperature of 350°C. Modelling of epitaxial growth showed that the interfacial energy is an important term responsible for 45° rotation of the TiN unit cell with respect to that of GaAs. The high strain energy associated with the coherent epilayer is reduced by domain epitaxial growth. These films were characterized using high-resolution TEM techniques, and experimental results were rationalized by thin film growth modeling.

Preparation and Characterization of La1Sr2Nb5O10−x Specimens

1990 ◽  
Vol 209 ◽  
Author(s):  
Donald H. Galvàn ◽  
M. Avalos-Borja ◽  
L. Cota-Araiza ◽  
J. Cruz-Reyes ◽  
E. A. Early
Keyword(s):  
High Temperature ◽  
High Resolution ◽  
X Rays ◽  
High Resolution Tem ◽  
Nominal Stoichiometry

ABSTRACTRecently Ogushi et al reported a La-Sr-Nb-O compound with a superconducting temperature of about 225 K. The possibility of having superconductors with such a high temperature is certainly technologically relevant. We prepared specimens with the same nominal stoichiometry and performed characterization by SEM, high resolution TEM, Scanning Auger and X-rays.

Microstructure characterization of a cobalt-oxide-doped cerium-gadolinium-oxide by analytical and high-resolution TEM

2007 ◽  
Vol 55 (8) ◽  
pp. 2907-2917 ◽  
Author(s):  
Zaoli Zhang ◽  
Wilfried Sigle ◽  
Manfred Rühle ◽  
Eva Jud ◽  
Ludwig J. Gauckler
Keyword(s):  
High Resolution ◽  
Cobalt Oxide ◽  
Gadolinium Oxide ◽  
Microstructure Characterization ◽  
High Resolution Tem ◽  
Cerium Gadolinium Oxide

EVOLUTION OF MICROSTRUCTURE AND PHASE COMPOSITION UPON ANNEALING OF LiFePO4 PREPARED BY A LOW TEMPERATURE METHOD

2011 ◽  
Vol 04 (02) ◽  
pp. 117-122 ◽  
Author(s):  
W. ZAJAC ◽  
J. MARZEC ◽  
W. MAZIARZ ◽  
A. RAKOWSKA ◽  
J. MOLENDA
Keyword(s):  
Electrical Conductivity ◽  
Phase Composition ◽  
High Resolution ◽  
Microstructural Characterization ◽  
Temperature Method ◽  
High Resolution Tem ◽  
Iron Valence ◽  
Evolution Of Microstructure ◽  
Type Crystal

The effect of annealing of nanosized LiFePO 4 powder on microstructure, phase composition, iron valence state and electrical conductivity has been studied. Careful microstructural characterization of the as-prepared powder using high resolution TEM revealed presence of {010}-type crystal planes at the surface of crystallites, which seem to be beneficial to electrochemical activity. The second part of the work is focused on explanation of presence and evolution of Fe 3+ detected in the material. Transmission and CEMS modes of Mössbauer spectroscopy together with TEM allowed for ruling out concept of amorphous layers containing Fe 3+ ions covering crystalline LiFePO 4 grains.

Crystallographic Characterization of Sputter Deposited Nb-Cu Thin Films Using Electron Backscatter Diffracted Patterns.

1999 ◽  
Vol 5 (S2) ◽  
pp. 256-257
Author(s):  
R. Loloee ◽  
W.P. Pratt ◽  
M. A. Crimp
Keyword(s):  
Thin Films ◽  
Ccd Camera ◽  
Crystallographic Structure ◽  
Camera System ◽  
Cu Films ◽  
Complementary Approach ◽  
Wide Range ◽  
Electron Backscatter ◽  
Sputter Deposited

Crystallographic structure plays an important role in determining the fundamental physical properties of metallic thin films and superlattices, and structural characterization of such films is crucial for furthering the application of these materials [1]. Epitaxial films are usually characterized using a wide range of techniques including x-ray diffraction, REED, neutron diffraction, and highresolution electron microscopy. A complementary approach is electron backscatter patterns (EBSP), which is an SEM technique that can be used to measure crystallographic orientations of single or polycrystals [2].In this work, EBSPs have been used to characterize the crystallite size and orientation of sputterdeposited Cu films. The EBSPs were formed in a CamScan 44FE SEM and recorded using an ORTEX CCD camera system. The images were analyzed using the Channel+ software package, and orientation maps were plotted using Channel+Ice [3].

Sign in / Sign up

Export Citation Format

Share Document