研究者詳細 - 石川　健治

論文 - 石川　健治

分割表示 355 件中 21 - 40 件目／全件表示 >>

Cooperation of Poly(rC)-binding Proteins 1/2 and Glutathione in Ferroptosis Induced by Plasma-activated Ringer's Lactate 査読有り

Zheng, H; Jiang, L; Lyu, QY; Akatsuka, S; Motooka, Y; Sekido, Y; Nakamura, K; Tanaka, H; Ishikawa, K; Kajiyama, H; Mizuno, M; Hori, M; Toyokuni, S

CANCER SCIENCE 114 巻頁： 749 - 749 2023年2月

Cooperation of Poly(rC)-binding Proteins 1/2 and Glutathione in Ferroptosis Induced by Plasmaactivated Ringer's Lactate 査読有り

Zheng, H; Jiang, L; Lyu, QY; Akatsuka, S; Motooka, Y; Sekido, Y; Nakamura, K; Tanaka, H; Ishikawa, K; Kajiyama, H; Mizuno, M; Hori, M; Toyokuni, S

CANCER SCIENCE 114 巻頁： 1340 - 1340 2023年2月

GaN damage-free cyclic etching by sequential exposure to Cl<sub>2</sub> plasma and Ar plasma with low Ar<SUP>+</SUP>-ion energy at substrate temperature of 400 °C 査読有り

Nakamura, S; Tanide, A; Kimura, T; Nadahara, S; Ishikawa, K; Oda, O; Hori, M

JOURNAL OF APPLIED PHYSICS 133 巻 ( 4 ) 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Applied Physics

Damage-free atomic layer etching (ALE) of GaN was demonstrated using a cyclic process in which the chlorinated layer formed by Cl2 plasma exposure was removed by exposure to Ar plasma with energy-controlled ions when the substrate temperature was maintained at 400 °C. The layer chlorinated at 400 °C by Cl2 plasma exposure was found to be thinner than that chlorinated at 25 °C. Therefore, in the case of an Ar+-ion energy of 70 eV, the "ALE synergy"parameter, which quantifies the degree to which a process approaches the ideal ALE regime, decreased from 86% at a substrate temperature of 25 °C to 24% at a substrate temperature of 400 °C. A substrate temperature of 400 °C promoted etching even at the lower ion energy of 40 eV, thereby resulting in a higher ALE synergy of 62%. The vertical etching profile with no degradation of photoluminescence near the band edge on the etched surface was then observed. The proposed high-temperature ALE method is promising for realizing a vertical pattern profile via damage-free etching of GaN.

DOI： 10.1063/5.0131685

Mechanical properties of maze-like carbon nanowalls synthesized by the radial injection plasma enhanced chemical vapor deposition method 査読有り

Ghodke, S; Murashima, M; Christy, D; Van Nong, N; Ishikawa, K; Oda, O; Umehara, N; Hori, M

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING 862 巻 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Materials Science and Engineering: A

The unique structural properties of vertically aligned graphene sheets or Carbon Nanowalls (CNWs) have attracted great interests for their potential for various applications in microelectronic devices, energy storage, and catalyst support materials. During the handling or operation of the devices, tension and/or pressure are often needed. Under such conditions, CNWs must undergo compression and stress. Therefore, the deformation mechanism and evolution behavior of the CNW structures under load play a critical role in the performance and reliability of the devices. In this study, the mechanical properties of a typical maze-like CNW structure synthesized by a Radial Injection Plasma Enhanced Chemical Vapor Deposition (RI-PECVD) technique were analyzed by employing the nanoindentation method. The measured compressive strength of the CNW structure was 50 MPa with an average modulus E value of ∼28 GPa, which is significantly higher than that of pyrolytic graphite and other graphene-based materials such as 3D graphene-derived carbon, commercial graphene, and reduced graphene oxide films. An elastoplastic behavior of a soft material was observed in high-resolution microscopy and a mechanism of deformation for CNWs is elucidated.

DOI： 10.1016/j.msea.2022.144428

Effects of plasma-activated Ringer's lactate solution on cancer cells: evaluation of genotoxicity 査読有り

Liu, Y; Nakatsu, Y; Tanaka, H; Koga, K; Ishikawa, K; Shiratani, M; Hori, M

GENES AND ENVIRONMENT 45 巻 ( 1 ) 頁： 3 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Genes and Environment

Background: Non-thermal atmospheric pressure plasma technologies form the core of many scientific advances, including in the electronic, industrial, and biotechnological fields. The use of plasma as a cancer therapy has recently attracted significant attention due to its cancer cell killing activity. Plasma-activated Ringer’s lactate solution (PAL) exhibits such activity. In addition to ROS, PAL contains active compounds or species that cause cancer cell death, but the potential mutagenic risks of PAL have not been studied. Results: PAL has a low pH value and a high concentration of H2O2. H2O2 was removed from PAL using catalase and catalase-treated PAL with a pH of 5.9 retained a killing effect on HeLa cells whereas this effect was not observed if the PAL was adjusted to pH 7.2. Catalase-treated PAL at pH 5.9 had no significant effect on mutation frequency, the expression of γH2AX, or G2 arrest in HeLa cells. Conclusion: PAL contains one or more active compounds or species in addition to H2O2 that have a killing effect on HeLa cells. The compound(s) is active at lower pH conditions and apparently exhibits no genotoxicity. This study suggested that identification of the active compound(s) in PAL could lead to the development of novel anticancer drugs for future cancer therapy.

DOI： 10.1186/s41021-023-00260-x

Editorial: Prospects of plasma generated species interaction with organic and inorganic materials 査読有り

Attri, P; Koga, K; Kurita, H; Ishikawa, K; Shiratani, M

FRONTIERS IN PHYSICS 10 巻 2023年1月

Plasma activated Ringer's lactate solution 査読有り

Tanaka, H; Mizuno, M; Ishikawa, K; Miron, C; Okazaki, Y; Toyokuni, S; Nakamura, K; Kajiyama, H; Hori, M

FREE RADICAL RESEARCH 57 巻 ( 1 ) 頁： 14 - 20 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Free Radical Research

Low-temperature plasma (LTP) has been widely used in life science. Plasma-activated solutions were defined as solutions irradiated with LTP, and water, medium, and Ringer’s solutions have been irradiated with LTP to produce plasma-activated solutions. They contain chemical compounds produced by reactions among LTP, air, and solutions. Reactive oxygen and nitrogen species (RONS) are major components in plasma-activated solutions and recent studies revealed that plasma-activated organic compounds are produced in plasma-activated Ringer’s lactate solution (PAL). Many in vitro and in vivo studies demonstrated that PAL exhibits anti-tumor effects on cancers, and biochemical analyses revealed intracellular molecular mechanisms of cancer cell death by PAL.

DOI： 10.1080/10715762.2023.2182663

Biocompatibility of conformal silicon carbide on carbon nanowall scaffolds 査読有り

Ono, K; Koide, T; Ishikawa, K; Tanaka, H; Kondo, H; Sugawara-Narutaki, A; Jin, Y; Yasuhara, S; Hori, M; Takeuchi, W

JAPANESE JOURNAL OF APPLIED PHYSICS 62 巻 ( SA ) 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Japanese Journal of Applied Physics

Silicon carbide (SiC) was coated onto carbon nanowall (CNW) scaffolds using chemical vapor deposition with a vinylsilane precursor at 700 °C to investigate the influence of the wall edge width, wall-to-wall distance, and surface morphology. The wall edge width ranged from 10 nm to those filling the wall-to-wall space without disrupting the CNW morphology. When SiC-coated CNWs (SiC/CNWs) were used as scaffolds for cell culture, cell viability increased until the edge area ratio reached 40%. In over 40% of edge area ratio, cell viability was saturate and comparable to flat surfaces such as SiC films on the Si substrate (SiC/Si) and control samples prepared using polystyrene. Calcification was suppressed in the CNWs, SiC/CNWs, and SiC/Si scaffolds compared to polystyrene. Our results suggest that SiC-coated CNW scaffolds could suppress calcification and promote cell proliferation.

DOI： 10.35848/1347-4065/ac9319

Science-based, data-driven developments in plasma processing for material synthesis and device-integration technologies 査読有り

Kambara, M; Kawaguchi, S; Lee, HJ; Ikuse, K; Hamaguchi, S; Ohmori, T; Ishikawa, K

JAPANESE JOURNAL OF APPLIED PHYSICS 62 巻 ( SA ) 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Japanese Journal of Applied Physics

Low-temperature plasma-processing technologies are essential for material synthesis and device fabrication. Not only the utilization but also the development of plasma-related products and services requires an understanding of the multiscale hierarchies of complex behaviors of plasma-related phenomena, including plasma generation in physics and chemistry, transport of energy and mass through the sheath region, and morphology- and geometry-dependent surface reactions. Low-temperature plasma science and technology play a pivotal role in the exploration of new applications and in the development and control of plasma-processing methods. Presently, science-based and data-driven approaches to control systems are progressing with the state-of-the-art deep learning, machine learning, and artificial intelligence. In this review, researchers in material science and plasma processing, review and discuss the requirements and challenges of research and development in these fields. In particular, the prediction of plasma parameters and the discovery of processing recipes are asserted by outlining the emerging science-based, data-driven approaches, which are called plasma informatics.

DOI： 10.35848/1347-4065/ac9189

Effects of High-Quality Carbon Nanowalls Ionization-Assisting Substrates on Surface-Assisted Laser Desorption/Ionization Mass Spectrometry Performance 査読有り

Sakai, R; Kondo, H; Ishikawa, K; Ohta, T; Hiramatsu, M; Tanaka, H; Hori, M

NANOMATERIALS 13 巻 ( 1 ) 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Nanomaterials

Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is performed using carbon nanowalls (CNWs) for ionization-assisting substrates. The CNWs (referred to as high-quality CNWs) in the present study were grown using a radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) system with the addition of oxygen in a mixture of CH4 and H2 gases. High-quality CNWs were different with respect to crystallinity and C–OH groups, while showing similar wall-to-wall distances and a wettability comparable to CNWs (referred to as normal CNWs) grown without O2. The efficiency of SALDI was tested with both parameters of ion intensity and fragmental efficiency (survival yield (SY)) using N-benzylpyridinuim chloride (N-BP-CI). At a laser fluence of 4 mJ/cm2, normal CNWs had an SY of 0.97 and an ion intensity of 0.13, while 5-sccm-O2– high-quality CNWs had an SY of 0.89 and an ion intensity of 2.55. As a result, the sensitivity for the detection of low-molecular-weight analytes was improved with the high-quality CNWs compared to the normal CNWs, while an SY of 0.89 was maintained at a low laser fluence of 4 mJ/cm2. SALDI-MS measurements available with the high-quality CNWs ionization-assisting substrate provided high ionization and SY values.

DOI： 10.3390/nano13010063

Selective isotropic atomic-layer etching of thin films by using dry chemical removal tool 査読有り

Shinoda K., Miyoshi N., Kobayashi H., Izawa M., Ishikawa K., Hori M.

Proceedings of SPIE - The International Society for Optical Engineering 12499 巻 2023年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Proceedings of SPIE - The International Society for Optical Engineering

There has been considerable interest in the development of isotropic atomic layer etching (ALE) for the conformal removal of thin films. Material selectivity is crucial for the development of isotropic ALE because the next generation of semiconductor devices will be constructed with miniaturized 3D structures using a variety of very thin films. We developed plasma-assisted thermal-cyclic ALE, which is a repetition of surface modification by plasma exposure and removal of the modified surface by infrared heating. We developed a 300-mm tool, namely, dry chemical removal (DCR), which is equipped with an inductively coupled plasma (ICP) source and infrared lamps, to facilitate rapid thermal desorption of the modified surface. An important feature of the plasma-assisted thermal-cyclic ALE is that it has more tuning knobs than that of conventional ALE because it uses two temperatures: a low temperature for surface modification and an elevated temperature for the removal of the modified surface. This paper presents the selective ALE of various materials, i.e., Si3N4, TiN, W, and SiGe using the developed tool. The mechanisms of the selectivity are divided into two categories: formation of an ammonium salt-based modified layer and selectivity control by adjusting the infrared heating time. This paper reviews the selective ALE mechanisms, focusing on the results of in situ analysis of surface reactions, and presents some of the latest findings.

DOI： 10.1117/12.2664547

Free radical formation induced by cold atmospheric plasma and its biological implications-Comparison with ionizing radiation- (低温大気圧プラズマによるフリーラジカル生成とその生物学的意義) 査読有り

田中宏昌, 石川健治

化学工業 74 巻頁： 120 - 126 2023年

低温大気圧プラズマによるフリーラジカル生成とその生物学的意義-放射線との比較-

近藤隆, 田中宏昌, 石川健治, 堀勝

化学工業 74(2) 巻頁： 120 - 126 2023年

Impact of microsecond-pulsed plasma-activated water on papaya seed germination and seedling growth 査読有り

Xi, DK; Zhang, XH; Yang, SZ; Yap, SS; Ishikawa, K; Hori, M; Yap, SL

CHINESE PHYSICS B 31 巻 ( 12 ) 2022年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Chinese Physics B

The seed of Carica papaya consists of a hard shell-like testa with inhibitors in vivo causing slow, erratic and asynchronous germination. In this work, plasma-activated water prepared by microsecond-pulsed plasma jets (μPAW) was applied to treat papaya seeds. The μPAW after plasma activation of 30 min was about 40 °C. The reactive species such as NO2, NO3, and H2O2 in the μPAW activated from deionized water were measured and correlated to the seed germination rate and the seedling growth performance. The μPAW-treated papaya seed achieved a higher germination rate of 90%, which is 26% higher than the control group using deionized water. Comparing the results with a hot water (40 °C) reference group showed that the reactive species in μPAW played primary roles in germination improvement, with little effect caused by the heat shock. The μPAW also sterilized the treated seeds, reducing the germination stress. The morphological change in the seeds was observed by SEM, showing an effect of physical etching after treatment promoting seed imbibition. The biochemical mechanism of the seed germination was deduced with reference to the evolution of surface chemistry, functional groups, and ABA content. The accelerated seed metabolism observed was corresponded to the chemical modification pathway. Besides, early seedlings developed from treated seeds were observed to be healthy, grow more leaves, and have better root structures. The content of MDA in the treated papaya seedlings decreased along with increased SOD and higher ion concentration. The μPAW that can be prepared at atmospheric pressure for bulk production offers a low-risk and cost-effective seed priming technology that may significantly increase the production of agricultural crops.

DOI： 10.1088/1674-1056/ac904e

Indoor Floor Heel Mark Removal Using Spark Discharges and Pressurized Airflow 査読有り

Sakamoto, Y; Tsutsumi, T; Tanaka, H; Ishikawa, K; Hashizume, H; Hori, M

COATINGS 12 巻 ( 12 ) 2022年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Coatings

Heel marks (HMs), which are the black stains made by shoe soles on indoor floors, can be difficult to remove. However, this study shows how spark discharges combined with pressurized airflow in 60 s discharge treatments can remove such HMs. We further show that maximizing the HM removal rates depended on the electrode gap distance because of changes in the spark discharge parameters. In our experiments, the electrical voltage waveforms are shown with voltage spikes, called spark discharges, and the spike numbers were counted in 0.6-ms time units. It was found that the number of spark discharges increases when the electrode gap distance was widened from 5 mm to 10 mm and the pressurized airflow was added, and the HM removal rates increased 11.5%, the HM removal rates could be maximized. Taken together, the results show that spark discharges combined with pressurized air can remove HMs from indoor floors without no visual damage. This paper is a preliminary report showing that HMs can be removed by plasma.

DOI： 10.3390/coatings12121938

Wide range applications of process plasma diagnostics using vacuum ultraviolet absorption spectroscopy 査読有り

Takeda K., Ishikawa K., Hori M.

Reviews of Modern Plasma Physics 6 巻 ( 1 ) 2022年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Reviews of Modern Plasma Physics

Applications of plasma diagnostics using vacuum ultraviolet absorption spectroscopy (VUVAS) in our studies are summarized in this article. The plasma diagnostics with absorption spectroscopy is a powerful tool for investigating behaviors of reactive species in plasma processes, because it enables us to measure the absolute density. In our group, we have focused on the clarification of reaction mechanisms of atomic species in the plasma processes, and the behaviors of atomic species generated in various process plasmas have been investigated using the VUVAS with a plasma light source. Using the VUVAS, we can investigate not only the absolute density but also surface reactions of atomic species in the plasma processes. On the other hand, in our group, the real-time monitoring of atomic species based on VUVAS has been realized in the plasma processes, and the effects of the initial state of reactor wall surface on the behaviors of atomic species in a process plasma have been quantitatively investigated. Moreover, the VUVAS has been applied to the measurements of reactive species generated by atmospheric pressure plasmas which attracts much attention because of its applications to the bio and medical research fields. These results and experimental technique used in our studies are extremely useful for the further developments of plasma processes such as etching, deposition, surface modification, bio-medical applications and so on in the future.

DOI： 10.1007/s41614-022-00075-3

Dry etching of ternary metal carbide TiAlC via surface modification using floating wire-assisted vapor plasma 査読有り

Nguyen, TTN; Shinoda, K; Hamamura, H; Maeda, K; Yokogawa, K; Izawa, M; Ishikawa, K; Hori, M

SCIENTIFIC REPORTS 12 巻 ( 1 ) 頁： 20394 2022年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Scientific Reports

Dry etching of ternary metal carbides TiAlC has been first developed by transferring from wet etching to dry etching using a floating wire (FW)-assisted Ar/ammonium hydroxide vapor plasma. FW-assisted non-halogen vapor plasma generated at medium pressure can produce high-density reactive radicals (NH, H, and OH) for TiAlC surface modifications such as hydrogenation and methylamination. A proposed mechanism for dry etching of TiAlC is considered with the formation of the volatile products from the modified layer.

DOI： 10.1038/s41598-022-24949-1

Carbon Layer Formation on Hexagonal Boron Nitride by Plasma Processing in Hydroquinone Aqueous Solution 査読有り

Inoue, K; Sakakibara, N; Goto, T; Ito, T; Shimizu, Y; Hakuta, Y; Ishikawa, K; Hori, M; Terashima, K

ACS APPLIED MATERIALS & INTERFACES 14 巻 ( 47 ) 頁： 53413 - 53420 2022年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACS Applied Materials and Interfaces

Although hexagonal boron nitride (hBN) is a thermally conductive and electrically insulating filler in composite materials, surface modification remains difficult, which limits its dispersibility and functionalization. In this study, carbon layer formation on hBN particles by plasma processing in hydroquinone aqueous solution was investigated as a surface modification technique. Carbon components with features of polymeric hydrogenated amorphous carbon were found to be uniformly distributed on the hydroquinone-aided plasma-modified hBN (HQpBN) particles. Electron spin resonance measurements revealed abundant unpaired electrons in HQpBN, indicating that defects were formed on hBN by plasma processing and that the carbon layer contained dangling bonds. The defects on hBN could help in the attachment of the carbon layer, whereas the dangling bonds could act as reactive sites for further functionalization. The carbon layer on HQpBN was successfully functionalized with isocyanate groups, thus confirming the ability of this carbon layer to facilitate surface modification. These results demonstrate that the carbon layer formed on hBN can provide a designable interface in organic/inorganic composite materials.

DOI： 10.1021/acsami.2c15951

Effects of deposition precursors of hydrogenated amorphous carbon films on the plasma etching resistance based on mass spectrometer measurements and machine learning analysis 査読有り

Kurokawa, J; Kondo, H; Tsutsumi, T; Ishikawa, K; Sekine, M; Hori, M

VACUUM 205 巻 2022年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Vacuum

In the growth of hydrogenated amorphous carbon (a-C:H) films by plasma enhanced chemical vapor deposition (PECVD) with H2, CH4 and C3H6 plasma, the gas phase reaction of active species and their contribution to properties of deposited a-C:H film were quantitatively investigated using appearance quadrupole mass spectrometry (QMS) and machine learning. The QMS measurement indicated that two-types of neutral radicals were generated by the dissociation and polymerization of the raw material gasses. A random forest regression model was employed as a prediction model to analyze the correlation between the neutral species and etching rates by molecular oxygen (O2) plasma without any stage bias, which were measured by in-situ ellipsometry. The coefficient of determination (R2), an indicator of the degree of prediction accuracy, was 0.906 and 0.584 for the training and test data, respectively. SHapley Additive exPlanations (SHAP), interpreting the random forest model, were used to quantitatively indicate the contribution of radicals to the etching rate, including their synergistic and secondary effects. They indicated that carbon-rich radicals, such as C3H3 and C5H5, contributed to a decrease in the etching rate, whereas hydrogen-rich radicals, such as CHx (x=1,2,3,4), C2H5, C4H9, and C5H9,11 induced an increase in the etching rate by the O2 plasma. (200 words)

DOI： 10.1016/j.vacuum.2022.111351

Dissociation channels of c-C<sub>4</sub>F<sub>8</sub> to C<sub>2</sub>F<sub>4</sub> in reactive plasma 査読有り

Hayashi, T; Ishikawa, K; Sekine, M; Hori, M; Lwayama, H

JAPANESE JOURNAL OF APPLIED PHYSICS 61 巻 ( 10 ) 2022年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Japanese Journal of Applied Physics

Progress in computational methods and personal computing has made possible more accurate estimations for primary dissociation channels and energies. The main dissociation route is revealed to be via the 7E excited state with an energy of 12.23 eV, which is composed of transitions from the highest occupied molecular orbital with b1 symmetry to some degenerate unoccupied e molecular orbitals. The main contributing e orbitals consisted of antibonding combination of C2F4 π-bonding orbitals. This degenerate 7E state is lowered by non-adiabatic transitions through the conical interactions on the dissociating route to 2C2F4, so the energy is finally relaxed at the dissociative second lowest 1E excited state leading to 2C2F4 production. In the electron attachment process, the calculated results show that the F- ion is produced from the excited states of the D4h c-C4F8- ion through conical interactions at the energies of 4.3 eV, 5.6 eV, and 5.0 eV, along the C-F dissociation route.

DOI： 10.35848/1347-4065/ac895e

　前のページ - 次のページ　

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18