Generation mechanism and suppression method of landing error of two successively deposited metal droplets caused by coalescence and solidification

The properties of metal/semiconductor interfaces have received considerable attention over the past few years, and the Al/GaAs system is of special interest because of its potential use in high-speed logic integrated optics, and microwave applications. For such materials a detailed knowledge of the geometric and electronic structure of the interface is fundamental to an understanding of the electrical properties of the contact. It is well known that the properties of Schottky contacts are established within a few atomic layers of the deposited metal. Therefore surface contamination can play a significant role. A method for fabricating contamination-free interfaces is absolutely necessary for reproducible properties, and molecularbeam epitaxy (MBE) offers such advantages for in-situ metal deposition under UHV conditions

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LVSEM: Past Present and Future

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180574 ◽

1990 ◽

Vol 48 (1) ◽

pp. 364-365

Author(s):

James B. Pawley

Keyword(s):

Field Emission ◽

Line Width ◽

Time Scales ◽

Silicon Oxide ◽

Beam Current ◽

High Brightness ◽

High Beam ◽

Fixed Charges ◽

Beam Voltage ◽

Deposited Metal

Past: In 1960 Thornley published the first description of SEM studies carried out at low beam voltage (LVSEM, 1-5 kV). The aim was to reduce charging on insulators but increased contrast and difficulties with low beam current and frozen biological specimens were also noted. These disadvantages prevented widespread use of LVSEM except by a few enthusiasts such as Boyde. An exception was its use in connection with studies in which biological specimens were dissected in the SEM as this process destroyed the conducting films and produced charging unless LVSEM was used.In the 1980’s field emission (FE) SEM’s came into more common use. The high brightness and smaller energy spread characteristic of the FE-SEM’s greatly reduced the practical resolution penalty associated with LVSEM and the number of investigators taking advantage of the technique rapidly expanded; led by those studying semiconductors. In semiconductor research, the SEM is used to measure the line-width of the deposited metal conductors and of the features of the photo-resist used to form them. In addition, the SEM is used to measure the surface potentials of operating circuits with sub-micrometer resolution and on pico-second time scales. Because high beam voltages destroy semiconductors by injecting fixed charges into silicon oxide insulators, these studies must be performed using LVSEM where the beam does not penetrate so far.

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A Suppression Method of Higher Harmonics Resonance in Distribution System

IEEJ Transactions on Power and Energy ◽

10.1541/ieejpes.131.737 ◽

2011 ◽

Vol 131 (9) ◽

pp. 737-746 ◽

Cited By ~ 1

Author(s):

Shouji Sugimura ◽

Tadashi Naitoh ◽

Atsushi Toyama ◽

Fumihiko Ohta

Keyword(s):

Distribution System ◽

Higher Harmonics ◽

Suppression Method

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The Influence of Deposited Metal Material Parameters on the Heat Transfer Process and Fluid Dynamics in the Welding Pool

Proceedings of the 15th International Heat Transfer Conference ◽

10.1615/ihtc15.cnd.008758 ◽

2014 ◽

Author(s):

Lige Tong ◽

Jingchen Gu ◽

Shaowu Yin ◽

Li Wang ◽

Shiwu Bai

Keyword(s):

Heat Transfer ◽

Fluid Dynamics ◽

Transfer Process ◽

Heat Transfer Process ◽

Welding Pool ◽

Material Parameters ◽

Metal Material ◽

Deposited Metal

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An Improved Low-Frequency Ripple Suppression Method for Modular Multilevel Converter in Variable-Speed Motor Drive Application

2020 23rd International Conference on Electrical Machines and Systems (ICEMS) ◽

10.23919/icems50442.2020.9290825 ◽

2020 ◽

Author(s):

Liting Bao ◽

Huan Yang ◽

Xiaowei Gu ◽

Rongxiang Zhao

Keyword(s):

Low Frequency ◽

Motor Drive ◽

Modular Multilevel Converter ◽

Variable Speed ◽

Multilevel Converter ◽

Suppression Method ◽

Variable Speed Motor

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Optimizing Gas-Assisted FIB Processes: The Importance of Oft-Ignored Secondary Parameters

ISTFA 2004: Conference Proceedings from the 30th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2004p0527 ◽

2004 ◽

Author(s):

C. Rue ◽

S. Herschbein ◽

C. Scrudato ◽

L. Fischer ◽

A. Shore

Keyword(s):

Focused Ion Beam ◽

Vacuum Chamber ◽

Ion Beam ◽

Memory Capacity ◽

Metal Films ◽

Deposited Metal ◽

Influence Process ◽

Focused Beams ◽

Gas Pressures

Abstract The efficiency of Gas-Assisted Etching (GAE) and depositions performed using the Focused Ion Beam (FIB) technique is subject to numerous factors. Besides the wellknown primary parameters recommended by the FIB manufacturer (pixel spacing, dwell time, and gas pressures), certain secondary factors can also have a pronounced effect on the quality of these gas-assisted FIB operations. The position of the gas delivery nozzle during XeF2 mills on silicon is examined and was found to affect both the milling speed and the texture on the floor of the FIB trench. Limitations arising from the memory capacity of the FIB computer can also influence process times and trench quality. Exposing the FIB vacuum chamber to TMCTS during SiO2 depositions is found to temporarily impede the performance of subsequent tungsten depositions, especially following heavy or prolonged TMCTS exposure. A delay period may be required to achieve optimal tungsten depositions following TMCTS use. Finally, the focusing conditions of the ion beam are found to have a significant impact on the resistance of FIB-deposited metal films. This effect is attributed to partial milling of the deposition film due to the intense current density of the collimated ion beam. The resistances of metal depositions performed with intentionally defocused ion beams were found to be lower than those performed with focused beams.

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Structure and properties of gas-dynamic coatings and evaluation of their use in sliding friction pairs

10.36652/1813-1336-2020-16-6-260-266 ◽

2020 ◽

pp. 260-266

Author(s):

V.E. Arkhipov ◽

T.I. Murav’eva ◽

M.S. Pugachev ◽

O.O. Shcherbakova

Keyword(s):

Aluminum Oxide ◽

Sliding Friction ◽

Metal Layer ◽

Structural Phase ◽

Mechanical Mixture ◽

Structural Factors ◽

Coating Structure ◽

Corundum Structure ◽

Deposited Metal ◽

Copper Zinc

The problems of changes in the coating structure depending on the composition of the sprayed mechanical mixture using copper particles and mixture of copper and zinc particles (" brass") and the effect of structural factors on the tribological properties of the deposited metal layer are considered. The results of X-ray structural, phase, chemical and durometric analyzes, as well as tribological testing of coatings are presented. It is found that structure with hardness of ≈102.7 HV is formed in the coating from mechanical mixture of particles of copper and aluminum oxide (corundum). Numerous pores are observed in the structure of the deposited metal layer, the main size of which does not exceed 2 μm. In the coating from mechanical mixture of particles copper, zinc and aluminum oxide (corundum), structure is formed based on copper with hardness of ≈106.5 HV, zinc — ≈49.7 HV, intermetallic compounds (γ- and ε-phases) — ≈168.7 HV, the mass fraction of which is 62.0, 7.9 and 24.2 %, respectively. Both coatings can be used in sliding friction pairs.

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