Article
Physics, Multidisciplinary
Song Liu-Qin, Jia Wen-Zhu, Dong Wan, Zhang Yi-Fan, Dai Zhong-Ling, Song Yuan-Hong
Summary: With the rapid development of integrated circuit technology, higher requirements for thin film performances are needed. This study used a two-dimensional fluid/MC model to investigate the influences of radial position, gas ratio, and gas pressure on the deposition of silicon oxide films in plasma-enhanced chemical vapor deposition. The results showed that the edge effect caused non-uniform deposition rate along the radial direction, but increasing N2O content, decreasing Ar content, and increasing gas pressure improved the uniformity.
ACTA PHYSICA SINICA
(2022)
Article
Physics, Fluids & Plasmas
Ho Jun Kim
Summary: The adjustment of gas pressure has been found to improve the deposition rate and uniformity of a plasma process, especially for the deposition of hydrogenated amorphous silicon film. The combination of high pressure with narrow electrode spacing can guarantee more efficient and uniform deposition.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Yong-Hyun Kim, Jong-Sik Kim, Dae-Chul Kim, Young-Woo Kim, Jong-Bae Park, Duk-Sun Han, Mi-Young Song
Summary: The energy and mass distributions of ions and radicals from different plasma sources were studied, revealing that ion energy is inversely proportional to mass. The measured species and density of ions and radicals provide valuable information for understanding plasma process outcomes.
Article
Physics, Fluids & Plasmas
Toshisato Ono, Uwe R. Kortshagen, Christopher J. Hogan
Summary: This study used laser light scattering to investigate trapping of submicrometer metal oxide particles near the upper electrode of a CCP reactor. The trapping location moved further from the electrode with decreased reactor pressure, and particle trapping appeared to be influenced by the material dielectric constant. Further research is needed to understand how particle material properties affect forces on particles in plasma and the role of ion drag forces in trapping.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Coatings & Films
Yeong-Min Lim, So-Yeong Park, You He, Young-Hun Hong, Chin-Wook Chung
Summary: A method for improving the plasma uniformity in capacitively coupled plasma (CCP) is developed by using a parallel capacitor. By adjusting the capacitance of the parallel capacitor, the current of other harmonic frequency components in the plasma is greatly reduced, resulting in a more sinusoidal waveform and improved plasma uniformity.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Chemistry, Multidisciplinary
Sung Il Cho, Hyun Keun Park, Surin An, Sang Jeen Hong
Summary: Plasma is crucial in semiconductor processes, especially in the miniaturization and integration of devices. However, the increase in wafer surface temperature caused by the high RF power has posed challenges to the etching process. This study investigates the plasma characteristics using invasive and non-invasive diagnostic methods and proposes a real-time calculation of heat flux to anticipate wafer temperatures and address ion heating issues.
APPLIED SCIENCES-BASEL
(2023)
Article
Materials Science, Multidisciplinary
Ho Jun Kim
Summary: This study analyzed the effect of dielectric elements on the radial uniformity of plasma in a capacitively coupled plasma deposition reactor for a 300 mm wafer process. It was found that dielectric elements with a lower dielectric constant can modify the spatial distributions of plasma parameters and achieve radial uniform plasma distribution by changing the wafer material and electrode material.
Article
Physics, Applied
Takumi Tominaga, Shinji Takayanagi, Takahiko Yanagitani
Summary: Negative-ion bombardment during the sputtering deposition of Scandium aluminum nitride (ScAlN) films has a significant effect on the crystallinity and piezoelectric properties of the films. The increase in negative ions with decreasing sputtering pressure leads to the deterioration of ScAlN film properties.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Kunihiro Kamataki, Daiki Nagamatsu, Tao Yang, Kohei Abe, Akihiro Yamamoto, Iori Nagao, Toshiaki Arima, Michihiro Otaka, Yuma Yamamoto, Daisuke Yamashita, Takamasa Okumura, Naoto Yamashita, Naho Itagaki, Kazunori Koga, Masaharu Shiratani
Summary: The study shows that amplitude modulation discharges can suppress the growth of nanoparticles in TEOS plasma, and there is a relationship between the growth of nanoparticles and plasma generation.
Article
Physics, Fluids & Plasmas
Yeong-Min Lim, You He, Jaewon Lee, Ju-Ho Kim, Kyung-Hyun Kim, Chin-Wook Chung
Summary: In a capacitively coupled plasma (CCP) with high densities or high conductivity, plasma generation efficiency can be improved by using an inductor in parallel with the powered electrode. A parallel resonance is utilized to reduce power loss in the system and increase power absorbed by the plasma. This method leads to increased ion density and voltage at the powered electrode.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Fluids & Plasmas
M. Klich, S. Wilczek, J. F. J. Janssen, R. P. Brinkmann, T. Mussenbrock, J. Trieschmann
Summary: An argon-xenon plasma is used as a model system for examining symmetric low-pressure radiofrequency discharges, with a focus on ion dynamics and energy distribution. The gas composition and driving voltage are found to significantly impact ion dynamics, with the mixing ratio acting as a control parameter for ion flux and impingement energy. A synergy effect between argon ionization and xenon ionization is also discovered and discussed.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Pavel Smirnov, Ruslan Kozakov, Jochen Schein
Summary: A novel design of a neutralizer-free plasma thruster is proposed, utilizing RF discharge for plasma generation and a magnetic nozzle configuration for acceleration. The characteristics of plasma plume and ions flux are investigated, and key parameters such as ions energy, flux, efficiencies, and thrust are estimated. The system produces an ion beam accelerated to 10 eV with power levels of 20 W and a mass flow of 1.2 mg/s, showing the acceleration due to the formation of an ambipolar electric field. Comparisons with other similar thrusters are also conducted.
APPLIED SCIENCES-BASEL
(2021)
Article
Materials Science, Multidisciplinary
Artem Martyanov, Ivan Tiazhelov, Sergey Savin, Valery Voronov, Vitaly Konov, Vadim Sedov
Summary: This study reports the complex effect of microwave plasma chemical vapor deposition conditions on the morphology, growth rate, and phase composition of polycrystalline diamond (PCD) films. It is found that diamond growth is possible even at ultrahigh methane concentrations, including 100% methane gas. Lower substrate temperatures facilitate the formation of higher-quality PCD films but result in lower growth rates. This research is an important step towards controlling the properties of CVD-grown PCD material for precise and flexible diamond production for various applications.
Article
Nanoscience & Nanotechnology
Alex Latyshev, Andrew G. Semenov, Andrei D. Zaikin
Summary: We investigate plasma oscillations in long electromagnetically coupled superconducting nanowires. We demonstrate that the presence of inter-wire coupling results in the split of plasma modes into two new modes propagating with different velocities. These plasma modes form an effective dissipative quantum environment that interacts with electrons in both wires and has significant implications for the low-temperature behavior of the system under consideration.
BEILSTEIN JOURNAL OF NANOTECHNOLOGY
(2022)
Article
Physics, Fluids & Plasmas
Hao Wu, Youyou Zhou, Jiamao Gao, Yanli Peng, Zhijiang Wang, Wei Jiang
Summary: Most plasma sources undergo a breakdown process involving energy injection and particle ionization, but the fast evolution process is not well understood. This study used a novel approach to examine the breakdown process of a capacitively coupled plasma, revealing it can be divided into three phases: pre-breakdown, transition, and post-breakdown.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Acoustics
Kentaro Masuda, Hiroyuki Komatsu, Daisuke Koyama, Mami Matsukawa
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2020)
Article
Physics, Applied
Leslie Bustamante, Masaya Saeki, Takashi Misaki, Mami Matsukawa
JAPANESE JOURNAL OF APPLIED PHYSICS
(2020)
Article
Multidisciplinary Sciences
Yuki Harada, Daisuke Koyama, Marina Fukui, Akira Emoto, Kentaro Nakamura, Mami Matsukawa
SCIENTIFIC REPORTS
(2020)
Article
Endocrinology & Metabolism
Hirokazu Yasui, Keita Yano, Yuki Kuzuhara, Masaya Ikegawa, Mami Matsukawa
CALCIFIED TISSUE INTERNATIONAL
(2020)
Article
Acoustics
Taiki Makino, Tsukasa Nakamura, Leslie Bustamante, Shinji Takayanagi, Daisuke Koyama, Mami Matsukawa
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2020)
Article
Biophysics
Manon Fraulob, Sophie Le Cann, Benjamin Voumard, Hirokazu Yasui, Keita Yano, Romain Vayron, Mami Matsukawa, Philippe Zysset, Guillaume Haiat
JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME
(2020)
Review
Endocrinology & Metabolism
Etsuko Ozaki, Mami Matsukawa, Isao Mano, Daisuke Matsui, Yutaro Yoneda, Misako Masumura, Teruhide Koyama, Isao Watanabe, Mizuho Maekawa, Satomi Tomida, Koichi Iwasa, Shiori Umemura, Nagato Kuriyama, Ritei Uehara
Article
Acoustics
Nagomi Murashima, Itsuki Michimoto, Daisuke Koyama, Mami Matsukawa
Summary: The study investigated the in-plane elastic character of ultrasonic waves in the skull by measuring longitudinal wave velocities in the MHz range. Anisotropic changes in wave velocity were observed in the outer and diploe layers of swine skulls, with the main trabecular alignment in the thick diploe layer perpendicular to the thickness direction and changing with position inside the skull. The degree of anisotropy ranged from 1.07-1.33, depending on position and swine sample, with differences in velocity angle between the outer and diploe layers.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2021)
Article
Physics, Multidisciplinary
Koki Hasegawa, Kengo Namekawa, Shinji Takayanagi, Iwaki Akiyama
Summary: A flexible-shaped ultrasonic array probe suitable for imaging in the brain in a high magnetic field MRI environment has been developed. The curvature of the probe was estimated using MRI, and experiments were conducted using a phantom mimicking the shape of a skull. The proposed beamforming technique showed a narrower beam width compared to the conventional method, demonstrating its feasibility for ultrasonic imaging through arbitrary curved surfaces.
FRONTIERS IN PHYSICS
(2021)
Article
Physics, Applied
Takumi Tominaga, Shinji Takayanagi, Takahiko Yanagitani
Summary: This study focuses on the numerical simulation of SAW propagation in c-axis-tilted ScAlN films on silicon substrates and the development of a fabrication technique. The results demonstrate that c-axis-tilted ScAlN films exhibit a higher electromechanical coupling coefficient, making them suitable for SAW device applications.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2022)
Article
Physics, Applied
Takumi Tominaga, Shinji Takayanagi, Takahiko Yanagitani
Summary: Negative-ion bombardment during the sputtering deposition of Scandium aluminum nitride (ScAlN) films has a significant effect on the crystallinity and piezoelectric properties of the films. The increase in negative ions with decreasing sputtering pressure leads to the deterioration of ScAlN film properties.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Acoustics
Tsukasa Nakamura, Mineaki Takata, Itsuki Michimoto, Daisuke Koyama, Mami Matsukawa
Summary: The study found that the electrical potentials of ultrasound transducers depend on the bone site, correlating well with the success rate of LIPUS therapy.
JASA EXPRESS LETTERS
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Takumi Tominaga, Shinji Takayanagi, Takahiko Yanagitani
PROCEEDINGS OF THE 2020 IEEE INTERNATIONAL ULTRASONICS SYMPOSIUM (IUS)
(2020)
Article
Acoustics
Daiko Sakata, Takashi Misaki, Masaya Saeki, Takuya Kikkawa, Daisuke Koyama, Mami Matsukawa
ACOUSTICAL SCIENCE AND TECHNOLOGY
(2020)
