The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Noritsugu Umehara - One of the best experts on this subject based on the ideXlab platform.
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Axial uniformity of diamond-like carbon film deposited on metal rod by using microwave–Sheath Voltage combination plasma
Surface & Coatings Technology, 2014Co-Authors: Xingrui Deng, Hiroyuki Kousaka, Yasuyuki Takaoka, Noritsugu UmeharaAbstract:Abstract We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100 μm/h) using microwave–Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1 cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at − 200 V. When the substrate Voltage was increased to − 500 V, the hardness of the DLC film measured by the nano-indenter was about 25 GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis.
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axial uniformity of diamond like carbon film deposited on metal rod by using microwave Sheath Voltage combination plasma
Surface & Coatings Technology, 2014Co-Authors: Xingrui Deng, Hiroyuki Kousaka, Yasuyuki Takaoka, Noritsugu UmeharaAbstract:Abstract We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100 μm/h) using microwave–Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1 cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at − 200 V. When the substrate Voltage was increased to − 500 V, the hardness of the DLC film measured by the nano-indenter was about 25 GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis.
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Axial uniformity of diamond-like carbon film deposited on metal rod by using microwave-Sheath Voltage combination plasma
Surface and Coatings Technology, 2014Co-Authors: Xingrui Deng, Yuji Takaoka, Hiroyuki Kousaka, Noritsugu UmeharaAbstract:We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100. μm/h) using microwave-Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1. cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at - 200. V. When the substrate Voltage was increased to - 500. V, the hardness of the DLC film measured by the nano-indenter was about 25. GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis. © 2013 Elsevier B.V.
Xingrui Deng - One of the best experts on this subject based on the ideXlab platform.
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Axial uniformity of diamond-like carbon film deposited on metal rod by using microwave–Sheath Voltage combination plasma
Surface & Coatings Technology, 2014Co-Authors: Xingrui Deng, Hiroyuki Kousaka, Yasuyuki Takaoka, Noritsugu UmeharaAbstract:Abstract We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100 μm/h) using microwave–Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1 cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at − 200 V. When the substrate Voltage was increased to − 500 V, the hardness of the DLC film measured by the nano-indenter was about 25 GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis.
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axial uniformity of diamond like carbon film deposited on metal rod by using microwave Sheath Voltage combination plasma
Surface & Coatings Technology, 2014Co-Authors: Xingrui Deng, Hiroyuki Kousaka, Yasuyuki Takaoka, Noritsugu UmeharaAbstract:Abstract We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100 μm/h) using microwave–Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1 cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at − 200 V. When the substrate Voltage was increased to − 500 V, the hardness of the DLC film measured by the nano-indenter was about 25 GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis.
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Axial uniformity of diamond-like carbon film deposited on metal rod by using microwave-Sheath Voltage combination plasma
Surface and Coatings Technology, 2014Co-Authors: Xingrui Deng, Yuji Takaoka, Hiroyuki Kousaka, Noritsugu UmeharaAbstract:We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100. μm/h) using microwave-Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1. cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at - 200. V. When the substrate Voltage was increased to - 500. V, the hardness of the DLC film measured by the nano-indenter was about 25. GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis. © 2013 Elsevier B.V.
J. M. Williamson - One of the best experts on this subject based on the ideXlab platform.
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effect of energetic electrons on near wall Sheath Voltage in the cathode region of a cold cathode direct current discharge
Physics of Plasmas, 2009Co-Authors: J. Blessington, S F Adams, V. I. Demidov, J. M. WilliamsonAbstract:It is experimentally demonstrated that energetic electrons originating from the cathode or produced in volumetric processes in the cathode region of a cold cathode direct current discharge can create a large potential drop in the near-wall Sheath. This Voltage drop may be much greater than kTe/e (where k is the Boltzmann constant, Te is the electron temperature, and e is the electron charge). Due to the large near-wall Sheath Voltage, slow and moderately energetic electrons cannot reach the wall and move toward the anode. Application of additional potentials to the wall can change the amount of energetic electrons reaching the wall. This effect can be used for regulation of the near-cathode plasma and near-wall Sheath properties and thus may be useful in technical applications.
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Effect of energetic electrons on near-wall Sheath Voltage in the cathode region of a cold cathode direct current discharge
Physics of Plasmas, 2009Co-Authors: J. Blessington, S F Adams, V. I. Demidov, J. M. WilliamsonAbstract:It is experimentally demonstrated that energetic electrons originating from the cathode or produced in volumetric processes in the cathode region of a cold cathode direct current discharge can create a large potential drop in the near-wall Sheath. This Voltage drop may be much greater than kT(e)/e (where k is the Boltzmann constant, T(e) is the electron temperature, and e is the electron charge). Due to the large near-wall Sheath Voltage, slow and moderately energetic electrons cannot reach the wall and move toward the anode. Application of additional potentials to the wall can change the amount of energetic electrons reaching the wall. This effect can be used for regulation of the near-cathode plasma and near-wall Sheath properties and thus may be useful in technical applications. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3257914]
Hiroyuki Kousaka - One of the best experts on this subject based on the ideXlab platform.
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effect of humidity on the friction properties of a c h and a c h si films deposited by pecvd employing microwave Sheath Voltage combination plasma
Japanese Journal of Applied Physics, 2019Co-Authors: Hiroyuki Kousaka, Ippei Tanaka, Tomoya Ikeda, Toshimitsu Nakano, Tatsuya FurukiAbstract:Si-doped diamond-like carbon (a-C:H:Si) films can be deposited at an ultra-high rate around 100 μm h−1 by using microwave Sheath-Voltage combination plasma (MVP), showing a friction coefficient of 0.05–0.1 similar to that of conventional a-C:H:Si films. However, the effect of humidity on the friction property of a-C:H:Si films deposited by MVP has not been studied. Thus, we investigate the frictional characteristics of a-C:H:Si films deposited on different duty ratios of 10, 30, and 50% using MVP, where a steel ball is slid against an a-C:H:Si film under dry conditions with 10%–50%RH. The a-C:H:Si film deposited on the low duty ratio of 10% became a polymeric structure. The friction coefficients of the a-C:H:Si films decreased with a decrease in the relative humidity. At the low relative humidity of 10%, it was shown that low friction below 0.06 is achieved by transfer film with the amorphous carbon structure formed on the mating ball.
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Spatio-temporal behavior of microwave Sheath-Voltage combination plasma source
Journal of Applied Physics, 2015Co-Authors: Hiroyuki Kousaka, Laxminarayan L. RajaAbstract:Microwave Sheath-Voltage combination Plasma (MVP) is a high density plasma source and can be used as a suitable plasma processing device (e.g., ionized physical vapor deposition). In the present report, the spatio-temporal behavior of an argon MVP sustained along a direct-current biased Ti rod is investigated. Two plasma modes are observed, one is an “oxidized state” (OS) at the early time of the microwave plasma and the other is “ionized sputter state” (ISS) at the later times. Transition of the plasma from OS to ISS results a prominent change in the visible color of the plasma, resulting from a significant increase in the plasma density, as measured by a Langmuir probe. In the OS, plasma is dominated by Ar ions, and the density is in amplitude order of 1011 cm−3. In the ISS, metal ions from the Ti rod contribute significantly to the ion composition, and higher density plasma (1012 cm−3) is produced. Nearly uniform high density plasma along the length of the Ti rod is produced at very low input microwave...
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axial uniformity of diamond like carbon film deposited on metal rod by using microwave Sheath Voltage combination plasma
Surface & Coatings Technology, 2014Co-Authors: Xingrui Deng, Hiroyuki Kousaka, Yasuyuki Takaoka, Noritsugu UmeharaAbstract:Abstract We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100 μm/h) using microwave–Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1 cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at − 200 V. When the substrate Voltage was increased to − 500 V, the hardness of the DLC film measured by the nano-indenter was about 25 GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis.
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Axial uniformity of diamond-like carbon film deposited on metal rod by using microwave–Sheath Voltage combination plasma
Surface & Coatings Technology, 2014Co-Authors: Xingrui Deng, Hiroyuki Kousaka, Yasuyuki Takaoka, Noritsugu UmeharaAbstract:Abstract We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100 μm/h) using microwave–Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1 cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at − 200 V. When the substrate Voltage was increased to − 500 V, the hardness of the DLC film measured by the nano-indenter was about 25 GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis.
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Axial uniformity of diamond-like carbon film deposited on metal rod by using microwave-Sheath Voltage combination plasma
Surface and Coatings Technology, 2014Co-Authors: Xingrui Deng, Yuji Takaoka, Hiroyuki Kousaka, Noritsugu UmeharaAbstract:We developed a novel method for the deposition of diamond-like carbon (DLC) films at high deposition rates (over 100. μm/h) using microwave-Sheath Voltage combination plasma. This method was applied for depositing a DLC film on a three-dimensional metal substrate, but we found that the film thickness was not uniform along the direction of microwave propagation. Hence, we investigated the factors affecting the axial uniformity of DLC film deposited on long metal rods (1. cm in diameter). Since the axial distribution of plasma was observed to affect the uniformity of DLC, we evaluated the axial distribution of ion density using a Langmuir Probe in Ar plasma that was generated along both DLC-coated and non-coated rods. The results showed that the ion density along the axis of the DLC-coated rod decayed at a shorter distance than that along the axis of the uncoated one. The Voltage of the ion Sheath presumably decreased owing to the Voltage drop in the DLC film with high resistivity, in accordance with the short microwave decay. The uniformity considerably improved by using a duty ratio of 50% for the pulsed operation of both the microwaves and the substrate bias at - 200. V. When the substrate Voltage was increased to - 500. V, the hardness of the DLC film measured by the nano-indenter was about 25. GPa, uniformly distributed along the rod axis. Raman results show that the film is typical DLC structure, and the structure shows good uniformity along the rod axis. © 2013 Elsevier B.V.
J. Blessington - One of the best experts on this subject based on the ideXlab platform.
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effect of energetic electrons on near wall Sheath Voltage in the cathode region of a cold cathode direct current discharge
Physics of Plasmas, 2009Co-Authors: J. Blessington, S F Adams, V. I. Demidov, J. M. WilliamsonAbstract:It is experimentally demonstrated that energetic electrons originating from the cathode or produced in volumetric processes in the cathode region of a cold cathode direct current discharge can create a large potential drop in the near-wall Sheath. This Voltage drop may be much greater than kTe/e (where k is the Boltzmann constant, Te is the electron temperature, and e is the electron charge). Due to the large near-wall Sheath Voltage, slow and moderately energetic electrons cannot reach the wall and move toward the anode. Application of additional potentials to the wall can change the amount of energetic electrons reaching the wall. This effect can be used for regulation of the near-cathode plasma and near-wall Sheath properties and thus may be useful in technical applications.
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Effect of energetic electrons on near-wall Sheath Voltage in the cathode region of a cold cathode direct current discharge
Physics of Plasmas, 2009Co-Authors: J. Blessington, S F Adams, V. I. Demidov, J. M. WilliamsonAbstract:It is experimentally demonstrated that energetic electrons originating from the cathode or produced in volumetric processes in the cathode region of a cold cathode direct current discharge can create a large potential drop in the near-wall Sheath. This Voltage drop may be much greater than kT(e)/e (where k is the Boltzmann constant, T(e) is the electron temperature, and e is the electron charge). Due to the large near-wall Sheath Voltage, slow and moderately energetic electrons cannot reach the wall and move toward the anode. Application of additional potentials to the wall can change the amount of energetic electrons reaching the wall. This effect can be used for regulation of the near-cathode plasma and near-wall Sheath properties and thus may be useful in technical applications. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3257914]