scholarly journals Planar nanosized field emission cathodes on the basis of graphene/semi-insulating silicon carbide fabricated by focused ion beam

2016 ◽  
Vol 741 ◽  
pp. 012011 ◽  
Author(s):  
L Jityaev ◽  
O A Ageev ◽  
A M Svetlichnyi ◽  
A S Kolomiytsev ◽  
O B Spiridonov
2011 ◽  
Vol 7 (4) ◽  
pp. 594-597
Author(s):  
Zhan-Shuo Hu ◽  
Fei-Yi Hung ◽  
Shoou-Jinn Chang ◽  
Bohr-Ran Huang ◽  
Bo-Cheng Lin ◽  
...  

JOM ◽  
2021 ◽  
Author(s):  
Alexander J. Leide ◽  
Richard I. Todd ◽  
David E. J. Armstrong

AbstractSilicon carbide is desirable for many nuclear applications, making it necessary to understand how it deforms after irradiation. Ion implantation combined with nanoindentation is commonly used to measure radiation-induced changes to mechanical properties; hardness and modulus can be calculated from load–displacement curves, and fracture toughness can be estimated from surface crack lengths. Further insight into indentation deformation and fracture is required to understand the observed changes to mechanical properties caused by irradiation. This paper investigates indentation deformation using high-resolution electron backscatter diffraction (HR-EBSD) and Raman spectroscopy. Significant differences exist after irradiation: fracture is suppressed by swelling-induced compressive residual stresses, and the plastically deformed region extends further from the indentation. During focused ion beam cross-sectioning, indentation cracks grow, and residual stresses are modified. The results clarify the mechanisms responsible for the modification of apparent hardness and apparent indentation toughness values caused by the compressive residual stresses in ion-implanted specimens.


Nanoscale ◽  
2021 ◽  
Author(s):  
Shuai Tang ◽  
Jie Tang ◽  
Yimeng Wu ◽  
You-Hu Chen ◽  
Jun Uzuhashi ◽  
...  

A single CeB6 nanoneedle structure has been fabricated using a focused ion beam (FIB) and it shows an excellent field emission current stability as well as a single emission spot.


2016 ◽  
Vol 858 ◽  
pp. 561-564 ◽  
Author(s):  
Masafumi Inaba ◽  
Kazuma Suzuki ◽  
Yu Hirano ◽  
Wataru Norimatsu ◽  
Michiko Kusunoki ◽  
...  

The electrical contact properties of silicon carbide (SiC) and carbon nanotubes (CNTs) were measured by conductive atomic force microscopy (C-AFM). A CNT forest was synthesized by SiC surface decomposition. Trenches, which electrically separate the conduction area, were fabricated using a focused ion beam (FIB) without a cover layer, and the resistance of each island was measured by C-AFM. From the dependence of the resistance on the CNT forest island size, the contact resistance between the CNTs and the SiC substrate was measured. By varying the dopant density in the SiC substrate, the Schottky barrier height was evaluated to be ~0.5 eV. This is slightly higher than a previously reported result obtained from a similar setup with a metal covering the CNT forest. We assumed that the damaged region existed in the islands, which is due to the trench formation by the FIB. The commensurate barrier height was obtained with the length of the damaged region assumed to be ~3 μm. Here, we could estimate the resistivity of a CNT/SiC interface without a cover layer. This indicates that a CNT forest on SiC is useful as a brief contact electrode.


2015 ◽  
Vol 821-823 ◽  
pp. 100-103
Author(s):  
Ta Ching Hsiao ◽  
Shen Tsao ◽  
Sergey Nagalyuk ◽  
Evgeny Mokhov

A specific transition metal is used as a dopant element in silicon carbide powders to create the compensation effect. According to ab-initio simulation, vanadium, chromium, and manganese-induced compensation decrease the lifetime of the acceptor carrier and cause higher resistance when boron is the main impurity. Since the silicon carbide lattice has low solubility, excess metal precipitates on the surface of powders, particularly on the grain boundaries. The compositions of matrix and precipitation in the powders reveal obvious differences between the two areas. The X-ray diffraction (XRD) pattern shows the structure of VSi2, which indicates the existence of a second phase. Dual-beam focused ion beam (DBFIB) is used to further analyze the geography inside the powders. A cross-section view by DBFIB shows a second phase in the grains with a composition similar to that in the grain boundary. Metal-doped silicon carbide powders are used as starting materials to conduct crystal growth with better dopant element distribution.


2012 ◽  
Vol 717-720 ◽  
pp. 889-892 ◽  
Author(s):  
Hamidreza Zamani ◽  
Seung Wan Lee ◽  
Amir Avishai ◽  
Christian A. Zorman ◽  
R. Mohan Sankaran ◽  
...  

We report on experimental explorations of using focused ion beam (FIB) nanomachining of different types of silicon carbide (SiC) thin membranes, for making robust, high-quality stencil masks for new emerging options of nanoscale patterning. Using thin films and membranes in polycrystalline SiC (poly-SiC), 3C-SiC, and amorphous SiC (a-SiC) with thicknesses in the range of t~250nm−1.6μm, we have prototyped a series of stencil masks, with nanoscale features routinely down to ~100nm.


2016 ◽  
Vol 173 ◽  
pp. 214-218
Author(s):  
N. Al Nasiri ◽  
E. Saiz ◽  
F. Giuliani ◽  
L.J. Vandeperre

2012 ◽  
Vol 1433 ◽  
Author(s):  
Andrew A. Woodworth ◽  
Ali Sayir ◽  
Philip G. Neudeck ◽  
Balaji Raghothamachar ◽  
Michael Dudley

ABSTRACTCommercially available bulk silicon carbide (SiC) has a high number (>2000/cm2) of screw dislocations (SD) that have been linked to degradation of high-field power device electrical performance properties. Researchers at the NASA Glenn Research Center have proposed a method to mass-produce significantly higher quality bulk SiC. In order for this bulk growth method to become reality, growth of long single crystal SiC fibers must first be achieved. Therefore, a new growth method, Solvent-Laser Heated Floating Zone (Solvent-LHFZ), has been implemented. While some of the initial Solvent-LHFZ results have recently been reported, this paper focuses on further characterization of grown crystals and their growth fronts. To this end, secondary ion mass spectroscopy (SIMS) depth profiles, cross section analysis by focused ion beam (FIB) milling and mechanical polishing, and orientation and structural characterization by X-ray transmission Laue diffraction patterns and X-ray topography were used. Results paint a picture of a chaotic growth front, with Fe incorporation dependant on C concentration.


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