Fluorescence Dynamics of Semiconductor Nanorod Clusters Studied by Correlated Atomic Force, Transmission Electron, and Fluorescence Microscopy

ABSTRACT Burkholderia species are bacterial soil inhabitants that are capable of interacting with a variety of eukaryotes, in some cases occupying intracellular habitats. Pathogenic and nonpathogenic Burkholderia spp., including B. vietnamiensis, B. cepacia, and B. pseudomallei, were grown on germinating spores of the arbuscular mycorrhizal fungus Gigaspora decipiens. Spore lysis assays revealed that all Burkholderia spp. tested were able to colonize the interior of G. decipiens spores. Amplification of specific DNA sequences and transmission electron microscopy confirmed the intracellular presence of B. vietnamiensis. Twelve percent of all spores were invaded by B. vietnamiensis, with an average of 1.5 × 106 CFU recovered from individual infected spores. Of those spores inoculated with B. pseudomallei, 7% were invaded, with an average of 5.5 × 105 CFU recovered from individual infected spores. Scanning electron and fluorescence microscopy provided insights into the morphology of surfaces of spores and hyphae of G. decipiens and the attachment of bacteria. Burkholderia spp. colonized both hyphae and spores, attaching to surfaces in either an end-on or side-on fashion. Adherence of Burkholderia spp. to eukaryotic surfaces also involved the formation of numerous fibrillar structures.

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Atomic Force and Total Internal Reflection Fluorescence Microscopy for the Study of Force Transmission in Endothelial Cells

Biophysical Journal ◽

10.1016/s0006-3495(00)76724-5 ◽

2000 ◽

Vol 78 (4) ◽

pp. 1725-1735 ◽

Cited By ~ 208

Author(s):

Anshu Bagga Mathur ◽

George A. Truskey ◽

W. Monty Reichert

Keyword(s):

Endothelial Cells ◽

Fluorescence Microscopy ◽

Total Internal Reflection ◽

Internal Reflection ◽

Total Internal Reflection Fluorescence ◽

Force Transmission ◽

Atomic Force

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Scanning tunneling microscopy and atomic force microscopy: New tools for biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155864 ◽

1989 ◽

Vol 47 ◽

pp. 778-779

Author(s):

CE Bracker ◽

P. K. Hansma

Keyword(s):

Physical Property ◽

Scanning Probe ◽

Scanning Tunneling ◽

Small Scale ◽

Tunneling Microscopy ◽

Force Microscopy ◽

New Family ◽

Small Probe ◽

Atomic Force ◽

Transmission Electron

A new family of scanning probe microscopes has emerged that is opening new horizons for investigating the fine structure of matter. The earliest and best known of these instruments is the scanning tunneling microscope (STM). First published in 1982, the STM earned the 1986 Nobel Prize in Physics for two of its inventors, G. Binnig and H. Rohrer. They shared the prize with E. Ruska for his work that had led to the development of the transmission electron microscope half a century earlier. It seems appropriate that the award embodied this particular blend of the old and the new because it demonstrated to the world a long overdue respect for the enormous contributions electron microscopy has made to the understanding of matter, and at the same time it signalled the dawn of a new age in microscopy. What we are seeing is a revolution in microscopy and a redefinition of the concept of a microscope.Several kinds of scanning probe microscopes now exist, and the number is increasing. What they share in common is a small probe that is scanned over the surface of a specimen and measures a physical property on a very small scale, at or near the surface. Scanning probes can measure temperature, magnetic fields, tunneling currents, voltage, force, and ion currents, among others.

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The Electrical Characterization and Physical Failure Analysis for Transistor Gate Leakage

ISTFA 2006: Conference Proceedings from the 32nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2006p0257 ◽

2006 ◽

Author(s):

Tsung-Te Li ◽

Chao-Chi Wu ◽

Jung-Hsiang Chuang ◽

Jon C. Lee

Keyword(s):

Failure Analysis ◽

Electrical Characterization ◽

Physical Analysis ◽

Gate Leakage ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Voltage Stress ◽

Leakage Site

Abstract This article describes the electrical and physical analysis of gate leakage in nanometer transistors using conducting atomic force microscopy (C-AFM), nano-probing, transmission electron microscopy (TEM), and chemical decoration on simulated overstressed devices. A failure analysis case study involving a soft single bit failure is detailed. Following the nano-probing analysis, TEM cross sectioning of this failing device was performed. A voltage bias was applied to exaggerate the gate leakage site. Following this deliberate voltage overstress, a solution of boiling 10%wt KOH was used to etch decorate the gate leakage site followed by SEM inspection. Different transistor leakage behaviors can be identified with nano-probing measurements and then compared with simulation data for increased confidence in the failure analysis result. Nano-probing can be used to apply voltage stress on a transistor or a leakage path to worsen the weak point and then observe the leakage site easier.

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Structural and Optical Properties of InAsSbBi Grown by Molecular Beam Epitaxy on Offcut GaSb Substrates

Photonics ◽

10.3390/photonics8060215 ◽

2021 ◽

Vol 8 (6) ◽

pp. 215

Author(s):

Rajeev R. Kosireddy ◽

Stephen T. Schaefer ◽

Marko S. Milosavljevic ◽

Shane R. Johnson

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Optical Quality ◽

X Ray Diffraction ◽

Interface Quality ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Lateral Variations

Three InAsSbBi samples are grown by molecular beam epitaxy at 400 °C on GaSb substrates with three different offcuts: (100) on-axis, (100) offcut 1° toward [011], and (100) offcut 4° toward [011]. The samples are investigated using X-ray diffraction, Nomarski optical microscopy, atomic force microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The InAsSbBi layers are 210 nm thick, coherently strained, and show no observable defects. The substrate offcut is not observed to influence the structural and interface quality of the samples. Each sample exhibits small lateral variations in the Bi mole fraction, with the largest variation observed in the on-axis growth. Bismuth rich surface droplet features are observed on all samples. The surface droplets are isotropic on the on-axis sample and elongated along the [011¯] step edges on the 1° and 4° offcut samples. No significant change in optical quality with offcut angle is observed.

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