Localized Charging Effects Resulting From Focused Ion Beam Processing Of Non-Conductive Materials

2003 ◽  
Vol 792 ◽  
Author(s):  
Marion. A. Stevens-Kalceff ◽  
S. Rubanov ◽  
P. R. Munroe

ABSTRACTFocused Ion Beam (FIB) systems employ a finely focussed beam of positively charged ions to process materials. Ion induced charging effects in non-conductive materials have been confirmed using Scanning Surface Potential Microscopy (SSPM). Significant localized residual charging is observed within the ion implanted micro-volumes of non-conductive materials both prior to and following the onset of sputtering. Characteristic observed surface potentials associated with the resultant charging have been modelled, giving insight into the charging processes during implantation and sputtering. The results of this work have implications for the processing and microanalysis of non-conductive materials in FIB systems.

2015 ◽  
Vol 12 (3) ◽  
pp. 825-834 ◽  
Author(s):  
R. Hoffmann ◽  
C. Kirchlechner ◽  
G. Langer ◽  
A. S. Wochnik ◽  
E. Griesshaber ◽  
...  

Abstract. Coccospheres of a cultured Emiliania huxleyi clone were sampled in the exponential growth phase and sectioned using a focused ion beam microscope. An average of 69 sections and the corresponding secondary electron micrographs per coccosphere provided detailed information on coccosphere architecture. The coccospheres feature 2–3 layers on average and 20 coccoliths per cell, of which only 15 can be seen in conventional scanning electron micrographs. The outer coccosphere diameter was positively correlated with the number of coccolith layers. By contrast, the inner coccosphere diameter (around 4.36 μm), and hence the cell diameter, was quasi-constant. Coccoliths were not evenly distributed across the coccosphere, resulting more often than not in one part of the coccosphere displaying more coccolith layers than the other. The architectural data allowed for the calculation of the PIC $/$ POC ratio, the density and the sinking velocity of individual cells. The correlation of these parameters has implications for the ongoing debate on the function of coccoliths.


2021 ◽  
Vol 22 (16) ◽  
pp. 8630
Author(s):  
Depicha Jindatip ◽  
Rebecca Wan-Yan Poh ◽  
Ken Fujiwara

Recently, another new cell type was found in the perivascular space called a novel desmin-immunopositive perivascular (DIP) cell. However, the differences between this novel cell type and other nonhormone-producing cells have not been clarified. Therefore, we introduced several microscopic techniques to gain insight into the morphological characteristics of this novel DIP cell. We succeeded in identifying novel DIP cells under light microscopy using desmin immunocryosection, combining resin embedding blocks and immunoelectron microscopy. In conventional transmission electron microscopy, folliculostellate cells, capsular fibroblasts, macrophages, and pericytes presented a flat cisternae of rough endoplasmic reticulum, whereas those of novel DIP cells had a dilated pattern. The number of novel DIP cells was greatest in the intact rats, though nearly disappeared under prolactinoma conditions. Additionally, focused ion beam scanning electron microscopy showed that these novel DIP cells had multidirectional processes and some processes reached the capillary, but these processes did not tightly wrap the vessel, as is the case with pericytes. Interestingly, we found that the rough endoplasmic reticulum was globular and dispersed throughout the cytoplasmic processes after three-dimensional reconstruction. This study clearly confirms that novel DIP cells are a new cell type in the rat anterior pituitary gland, with unique characteristics.


Author(s):  
Yuanjing (Jane) Li ◽  
Steven Scott ◽  
Howard Lee Marks

Abstract This paper presents a backside chip-level physical analysis methodology using backside de-processing techniques in combination with optimized Scanning Electron Microscopic (SEM) imaging technique and Focused Ion Beam (FIB) cross sectioning to locate and analyze defects and faults in failing IC devices. The case studies illustrate the applications of the method for 28nm flip chip bulk Si CMOS devices and demonstrate how it is used in providing insight into the fab process and design for process and yield improvements. The methods are expected to play an even more important role during 20-nm process development and yield-ramping.


2005 ◽  
Vol 109 (47) ◽  
pp. 22205-22211 ◽  
Author(s):  
Hong-Li Zhang ◽  
Feng Li ◽  
Chang Liu ◽  
Jun Tan ◽  
Hui-Ming Cheng

2015 ◽  
Vol 309 (12) ◽  
pp. F1082-F1089 ◽  
Author(s):  
Tillmann Burghardt ◽  
Florian Hochapfel ◽  
Benjamin Salecker ◽  
Christine Meese ◽  
Hermann-Josef Gröne ◽  
...  

Podocytes constitute the outer layer of the glomerular filtration barrier, where they form an intricate network of interdigitating foot processes which are connected by slit diaphragms. A hitherto unanswered puzzle concerns the question of whether slit diaphragms are established between foot processes of the same podocyte or between foot processes of different podocytes. By employing focused ion beam-scanning electron microscopy (FIB-SEM), we provide unequivocal evidence that slit diaphragms are formed between foot processes of different podocytes. We extended our investigations of the filtration slit by using dual-axis electron tomography of human and mouse podocytes as well as of Drosophila melanogaster nephrocytes. Using this technique, we not only find a single slit diaphragm which spans the filtration slit around the whole periphery of the foot processes but additional punctate filamentous contacts between adjacent foot processes. Future work will be necessary to determine the proteins constituting the two types of cell-cell contacts.


Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 3928
Author(s):  
Svyatoslav Chugunov ◽  
Nikolaus A. Adams ◽  
Iskander Akhatov

Evolution of additively manufactured (AM) ceramics’ microstructure between manufacturing stages is a hardly explored topic. These data are of high demand for advanced numerical modeling. In this work, 3D microstructural models of Al2O3 greenbody, brownbody and sintered material are presented and analyzed, for ceramic samples manufactured with SLA-based AM workflow, using a commercially available ceramic paste and 3D printer. The novel data, acquired at the micro- and mesoscale, using Computed Tomography (CT), Scanning Electron Microscopy (SEM) and Focused Ion-Beam SEM (FIB/SEM) techniques, allowed a deep insight into additive ceramics characteristics. We demonstrated the spatial 3D distribution of ceramic particles, an organic binder and pores at every stage of AM workflow. The porosity of greenbody samples (1.6%), brownbody samples (37.3%) and sintered material (4.9%) are analyzed. Pore distribution and possible originating mechanisms are discussed. The location and shape of pores and ceramic particles are indicative of specific physical processes driving the ceramics manufacturing. We will use the presented microstructural 3D models as input and verification data for advanced numerical simulations developed in the project.


2001 ◽  
Vol 695 ◽  
Author(s):  
Myoung-Woon Moon ◽  
Kyang-Ryel Lee ◽  
Jin-Won Chung ◽  
And Kyu Hwan Oh

ABSTRACTThe topology of telephone cord buckles that form beneath compressed diamond-like carbon films (DLC) on glass substrates has been characterized with Atomic Force Microscopy (AFM) and with the Focused Ion Beam (FIB). Using AFM with 2nm resolution, the wavelength and amplitude of the buckles and their profiles have been measured. It has been found that, within each wavelength, the profile has symmetric and asymmetric segments. These changes have been related to differences in local mode mixity around the periphery of each repeat unit along the buckle, resulting in a fundamental rationale for the factors governing the wavelength. Sections made through various segments of the buckle by using the FIB imaging system result in local changes in the shape and size of the buckles that provide further insight into the buckle propagation criterion.


2019 ◽  
Vol 123 (16) ◽  
pp. 10639-10645 ◽  
Author(s):  
Suvasthika Indrajith ◽  
Patrick Rousseau ◽  
Bernd A. Huber ◽  
Chiara Nicolafrancesco ◽  
Alicja Domaracka ◽  
...  

2001 ◽  
Vol 706 ◽  
Author(s):  
Sandra B. Schujman ◽  
Robert Vajtai ◽  
Yuriy Shusterman ◽  
Sujit Biswas ◽  
Brian Dewhirst ◽  
...  

AbstractIn order to build electrical devices based on carbon nanotubes, it is crucial to understand the effects of the substrate, electrical contacts, defects and junctions on the transport properties of both multi-wall and single-wall carbon nanotubes (MWNT and SWNT). In the present study two different dispositions are analyzed. In one of them, isolated MWNT were deposited onto an insulating oxide layer over a conducting substrate and platinum electrical contacts were prepared via a focused ion beam (FIB) deposition method. An ohmic contact to the substrate allowed us to polarize it at a different potential than the nanotubes themselves. In the second one, a vertical array of MWNT was grown on a template of alumina in which one of the ends was coated with gold, to provide an electric contact. To investigate transport properties, we used an atomic force microscope (AFM) to determine the electric surface potential of MWNT. The technique employed, scanning surface potential microscopy (SSPM), applied a dc-voltage to the tip that equilibrates the local electrostatic potential on the sample so as to eliminate forces on the AFM tip caused by electric repulsion or attraction between tip and sample. There is no alteration of the sample potential caused by the tip. Surface potential measurements on the first system show that the electric transport on the MWNT has a diffusive character. The application of a (4.5V) bias between nanotube and substrate causes the resistance of the nanotube to drop by a factor of four. We can also resolve the voltage drop on the nanotube and at the contacts. The measurements in the second system (vertical arrangement) show that the nanotubes are uncapped and we can observe a contrast that varies with the application of different voltages to the back contact.


2014 ◽  
Vol 11 (9) ◽  
pp. 12773-12797 ◽  
Author(s):  
R. Hoffmann ◽  
C. Kirchlechner ◽  
G. Langer ◽  
A. S. Wochnik ◽  
E. Griesshaber ◽  
...  

Abstract. Coccospheres of a cultured Emiliania huxleyi clone were sampled in the exponential growth phase and sectioned using a focused ion beam microscope. An average of 69 sections and the corresponding secondary electron micrographs per coccosphere provided detailed information on coccosphere architecture. The latter features, 2–3 layers on average and 20 coccoliths per cell, of which only 15 can be seen in conventional scanning electron micrographs. The outer coccosphere diameter was positively correlated with the number of coccolith layers. By contrast, the inner coccosphere diameter (around 4.36 μm), and hence the cell diameter, was quasi-constant. Coccoliths were not evenly distributed across the coccosphere, resulting more often than not, in one part of the coccosphere displaying more coccolith layers than the other. The architectural data allowed us to calculate, with sufficient accuracy, the PIC/POC ratio and the density of individual cells. The lack of a significant correlation of the latter parameters has implications for the ongoing debate on the function of coccoliths.


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