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和泉 篤士*; 首藤 靖幸*; 柴山 充弘*; 宮田 登*; 宮崎 司*; 青木 裕之
Langmuir, 37(47), p.13867 - 13872, 2021/11
被引用回数：2 パーセンタイル：30.08(Chemistry, Multidisciplinary)The structural formation mechanism of phenolic resin-silica interfaces was investigated in situ by neutron reflectometry during curing. There was a 4 nm thick novolac resin adsorption layer on the silica surface before curing. The curing reaction of the novolac resin with hexamethylenetetramine (HMTA) increased the coherent neutron scattering length density of the resin due to the cure shrinkage accompanied by the volatilization of ammonia, which is a byproduct of HMTA decomposition. As curing proceeded at 180
C, the thickness of the bulk layer increased despite the cure shrinkage, and the thickness of the interfacial layer decreased from 4 to 1 nm. This is attributed to the diffusion of decomposed HMTA fragments generated in the bulk layer into the interfacial novolac adsorption layer during diffusion throughout the bulk layer, incorporating the upper part of the interfacial layer reacting with the fragment into the bulk layer. On the other hand, the fragments could not diffuse into the tightly bound immobile segments of novolac resin in direct contact with the silica surface, retaining the 1-2 nm thick interfacial layer in the cured resin. This structural formation mechanism caused interfacial cross-link inhomogeneity in the cured resin on the silica surface.
丸山 龍治; 山崎 大; 青木 裕之; 阿久津 和宏*; 花島 隆泰*; 宮田 登*; 曽山 和彦; Bigault, T.*; Saerbeck, T.*; Courtois, P.*
Journal of Applied Physics, 130(8), p.083904_1 - 083904_10, 2021/08
被引用回数：2 パーセンタイル：34.91(Physics, Applied)Ferromagnetic (FM) interlayer exchange coupling of ion-beam sputtered Fe/Ge multilayers was investigated by off-specular polarized neutron scattering measurements. We observed a monotonously growing correlation of magnetic moments in the out-of-plane direction with decreasing Ge thickness. The results of the Fe/Ge multilayers were used to invoke FM interlayer exchange coupling in a neutron polarizing supermirror in order to extend its bandwidth. Typically, the bandwidth is limited due to a Curie temperature close to room temperature of the thinnest Fe layers with less than 3 nm. We propose a modified layer sequence of the neutron polarizing supermirror, where the minimum Fe thickness was set to 3.5 nm whereas the Ge thickness was reduced. A performance test of the neutron polarizing supermirror showed that the FM interlayer exchange coupling contributed to the presence of the magnetization comparable to the bulk and resulted in a marked extension in the bandwidth.
宮崎 司*; 宮田 登*; 有馬 寛*; 吉良 弘*; 大内 啓一*; 笠井 聡*; 津村 佳弘*; 青木 裕之
Langmuir, 37(32), p.9873 - 9882, 2021/08
被引用回数：4 パーセンタイル：53.65(Chemistry, Multidisciplinary)We investigated the structure of the crystalline adsorption layer of poly(vinyl alcohol) (PVA) in hot water by neutron reflectivity in two cases: when the adsorption layer is exposed on the substrate by leaching the upper bulk layer and when it is deeply embedded between a relatively thick PVA film and substrate. In both cases, the PVA adsorption layer consists of three layers on the Si substrate. The bottom layer, consisting of amorphous chains that are strongly constrained on the substrate, is not swollen even in hot water at 90C. The middle layer, consisting of amorphous chains that are much more mobile compared with those in the bottom layer, has no freedom to assume a crystalline form. Only the molecular chains in the top layer are crystallizable in the adsorption layer, leading to a heterogeneous layered structure in the film thickness direction. This layered structure is attributed to the crystallizable chains of PVA during the formation of the adsorption layer driven by hydrogen bonding. However, the structure and dynamics in the adsorption layer may differ in both cases because the molecular chains in the vicinity of the surface seem to be affected by surface effects even in the adsorption layer.
丸山 龍治; 山崎 大; 阿久津 和宏*; 花島 隆泰*; 宮田 登*; 青木 裕之; 曽山 和彦
JPS Conference Proceedings (Internet), 33, p.011092_1 - 011092_6, 2021/03
中性子偏極スーパーミラーは、熱及び冷中性子ビームを偏極するための光学素子であり、実機への応用には高偏極率であるとともに必要な外部磁場を小さく抑えること、即ち偏極スーパーミラーを構成する磁気多層膜が磁気的にソフトであることが重要である。本発表では、J-PARC MLFの共用ビームラインBL17等を用いて得られた偏極スーパーミラーの高偏極率化、及び磁気多層膜の軟磁性化を目指しこれを構成する多層膜特有の磁気特性の解明に関する成果について議論する。
阿久津 和宏*; 吉良 弘*; 宮田 登*; 花島 隆泰*; 宮崎 司*; 笠井 聡*; 山崎 大; 曽山 和彦; 青木 裕之
Polymers (Internet), 12(10), p.2180_1 - 2180_10, 2020/10
被引用回数：2 パーセンタイル：11.82(Polymer Science)A large background scattering originating from the sample matrix is a major obstacle for fine-structure analysis of a nanometric layer buried in a bulk material. As polarization analysis can decrease undesired scattering in a neutron reflectivity (NR) profile, we performed NR experiments with polarization analysis on a polypropylene (PP)/perhydropolysilazane-derived SiO
(PDS)/Si substrate sample, having a deep-buried layer of SiO to elucidate the fine structure of the nano-PDS layer. This method offers unique possibilities for increasing the amplitude of the Kiessig fringes in the higher scattering vector (Qz) region of the NR profiles in the sample by decreasing the undesired background scattering. Fitting and Fourier transform analysis results of the NR data indicated that the synthesized PDS layer remained between the PP plate and Si substrate with a thickness of approximately 109 
;. Furthermore, the scattering length density of the PDS layer, obtained from the background subtracted data appeared to be more accurate than that obtained from the raw data. Although the density of the PDS layer was lower than that of natural SiO, the PDS thin layer had adequate mechanical strength to maintain a uniform PDS layer in the depth-direction under the deep-buried condition.
和泉 篤士*; 首藤 靖幸*; 柴山 充弘*; 吉田 鉄生*; 宮田 登*; 宮崎 司*; 青木 裕之
Macromolecules, 53(10), p.4082 - 4089, 2020/05
被引用回数：6 パーセンタイル：40.96(Polymer Science)The interfacial structure of a hexamethylenetetramine-cured phenolic resin on a silica surface was investigated by the complementary use of X-ray and neutron reflectivity (XRR and NR, respectively). The contrast-variation technique was applied using DO for the NR analysis in which the coherent neutron scattering length density (SLD) largely changed owing to the DO absorption of the dry phenolic resin and the hydrogen-to-deuterium exchange of phenolic hydroxyl groups. The XRR profile indicated no clear interfacial structure in terms of the mass density, whereas the NR profile indicated the presence of an interfacial nanolayer on the native silica surface according to the SLD. The thickness of the interfacial layer was 1-2 nm, which was independent of the thickness of the bulk resin layer. The formation of the interfacial layer on the silica surface could be caused by preferential adsorption of the novolac resin on the silica surface via strong hydrogen bonding between phenolic units in the novolac resin and silica surface comprising silanol and silyl ether groups resulting in interfacial cross-link inhomogeneity of the phenolic resin on the silica surface in the thickness direction. To the best of our knowledge, this is the first report of an experimental elucidation of the buried interfacial structure between the phenolic resins on the silica surface at a nanometer level.
宮崎 司*; 宮田 登*; 吉田 鉄生*; 有馬 寛*; 津村 佳弘*; 鳥飼 直也*; 青木 裕之; 山本 勝宏*; 金谷 利治*; 川口 大輔*; et al.
Langmuir, 36(13), p.3415 - 3424, 2020/04
被引用回数：11 パーセンタイル：66.04(Chemistry, Multidisciplinary)We investigated in detail the structures in the poly(vinyl alcohol) (PVA) adsorption layers on a Si substrate, which remained on the substrate after immersing the relatively thick 30 - 50 nm films in hot water, by neutron reflectometry under humid conditions. For the PVA with a degree of saponification exceeding 98 mol %, the adsorption layer exhibits a three-layered structure in the thickness direction. The bottom layer is considered to be the so-called inner adsorption layer that is not fully swollen with water vapor. This may be because the polymer chains in the inner adsorption layer are strongly constrained onto the substrate, which inhibits water vapor penetration. The polymer chains in this layer have many contact points to the substrate via the hydrogen bonding between the hydroxyl groups in the polymer chain and the silanol groups on the surface of the Si substrate and consequently exhibit extremely slow dynamics. Therefore, it is inferred that the bottom layer is fully amorphous. Furthermore, we consider the middle layer to be somewhat amorphous because parts of the molecular chains are pinned below the interface between the middle and bottom layers. The molecular chains in the top layer become more mobile and ordered, owing to the large distance from the strongly constrained bottom layer; therefore, they exhibit a much lower degree of swelling compared to the middle amorphous layer. Meanwhile, for the PVA with a much lower degree of saponification, the adsorption layer structure consists of the two-layers. The bottom layer forms the inner adsorption layer that moderately swells with water vapor because the polymer chains have few contact points to the substrate. The molecular chains in the middle layer, therefore, are somewhat crystallizable because of this weak constraint.
宮崎 司*; 宮田 登*; 浅田 光則*; 津村 佳弘*; 鳥飼 直也*; 青木 裕之; 山本 勝宏*; 金谷 利治*; 川口 大輔*; 田中 敬二*
Langmuir, 35(34), p.11099 - 11107, 2019/08
被引用回数：19 パーセンタイル：72.75(Chemistry, Multidisciplinary)We investigated the swelling behaviors of poly(vinyl alcohol) (PVA) films deposited on Si wafers with water vapor, which is a good solvent for PVA for elucidating structural and dynamical heterogeneities in the film thickness direction. Using deuterated water vapor, structural and dynamical differences in the thickness direction can be detected easily as different degrees of swelling in the thickness direction by neutron reflectivity. Consequently, the PVA film with a degree of saponification exceeding 98 mol % exhibits a three-layered structure in the thickness direction. It is considered that an adsorption layer consisting of molecular chains that are strongly adsorbed onto the solid substrate is formed at the interface with the substrate, which is not swollen with water vapor compared with the bulk-like layer above it. The adsorption layer is considered to exhibit significantly slower dynamics than the bulk. Furthermore, a surface layer that swells excessively compared with the underneath bulk-like layer is found. This excess swelling of the surface layer may be related to a higher mobility of the molecular chains or lower crystallinity at the surface region compared to the underneath bulk-like layer. Meanwhile, for the PVA film with a much lower degree of saponification, a thin layer with a slightly lower degree of swelling than the bulk-like layer above it can be detected at the interface between the film and substrate only under a high humidity condition. This layer is considered to be the adsorption layer composed of molecular chains loosely adsorbed onto the Si substrate.
河村 聖子; 服部 高典; Harjo, S.; 池田 一貴*; 宮田 登*; 宮崎 司*; 青木 裕之; 渡辺 真朗; 坂口 佳史*; 奥 隆之
Neutron News, 30(1), p.11 - 13, 2019/05
日本の中性子散乱施設の特徴のひとつとして、循環型冷凍機のように頻繁に使われる試料環境(SE)機器は各装置の担当者が整備していることが挙げられる。装置担当者は、ユーザー実験の際、装置自体だけでなく、これらのSE機器の運用も行う。このような運用には、SE機器を装置にあわせて最適化できユーザーの要求を直接きくことができるというメリットがある。一方で、MLFのSEチームは、より高度なSE機器を使った実験を可能にするため、共通のSE機器を整備している。本レポートでは、最近のMLFにおけるSE機器の現状が紹介される。中性子装置BL11, BL19, BL21, BL17で用いられるSE機器と、SEチームによって最近整備された機器に焦点をあてる。
丸山 龍治; 山崎 大; 阿久津 和宏*; 花島 隆泰*; 宮田 登*; 青木 裕之; 武田 全康; 曽山 和彦
Nuclear Instruments and Methods in Physics Research A, 888, p.70 - 78, 2018/04
被引用回数：3 パーセンタイル：35.39(Instruments & Instrumentation)イオンビームスパッタ法で成膜されたFe/Si及びFe/Ge多層膜に対して、X線及び偏極中性子反射率、走査型透過電子顕微鏡と組み合わされたエネルギー分散型X線分光分析等のプローブによって層構造や局所元素分析を行った。その結果、Fe/Ge多層膜のGe層に含まれたスパッタリングガスであるArが含まれることにより、Ge層の散乱長密度が減少し、(-)スピンの中性子に対するFeとGeの散乱長密度のコントラストがほぼ消失し偏極中性子反射において高偏極率となることがわかった。Ge層に含まれるArは、成膜時においてAeがGeターゲットで後方散乱することに起因することが知られており、偏極スーパーミラーの高偏極率化に必要な(-)スピン中性子に対する散乱長密度コントラストを微調整する新たな手法となる可能性を示すものである。この結果を基に、Niの5倍の全反射臨界角をもつFe/Ge偏極スーパーミラーを成膜し偏極反射率測定を行った結果、(+)スピン中性子の反射率が0.70以上、偏極率はビームラインの偏極性能が正しく補正されている領域においては0.985以上という高い偏極率を達成した。
宮田 登; 石川 禎之*; 柳原 美広*; 渡邊 誠*
Photon Factory News, 18(2), p.25 - 29, 2000/08
軟X線発光分光はプローブである軟X線の脱出深さが比較的長く、固体中の十分深い箇所からの発光が観測できるので、表面に依存しない、物質内部の結合状態を評価できる手法である。特に放射光による大強度単色軟X線で励起した場合には、用いる波長により特定の物質を励起できることもあり、2つの物質が接した際の境界面である「埋もれた」界面の結合状態を効率的に、試料を破壊することなく評価することができる。この手法により、近年軟X線光学や半導体製造技術で注目されているMoとSiの「埋もれた」界面の結合状態を評価した。Si膜厚の異なる5種類の多層膜試料を用意し、それらからのSiI
発光スペクトルの測定を行い、それらを参照試料からのスペクトルと比較し。その結果、界面ではMo
Siが約8できていることを示した。さらに、この多層膜をアニールすると界面層はMoSiに変化することを示した。
小池 雅人; 波岡 武*; Gullikson, E. M.*; 原田 善寿*; 石川 禎之*; 今園 考志*; Mrowka, S.*; 宮田 登; 柳原 美広*; Underwood, J. H.*; et al.
Soft X-Ray and EUV Imaging Systems (Proceedings of SPIE Vol.4146), p.163 - 170, 2000/00
軟X線領域においてラミナー型ホログラフィック回折格子が、迷光や高次光が少なく、特にkeVに至る短波長域での回折効率に優れるなどの点から注目されている。しかし、レーザープラズマ分光等で広く用いられている平面結像斜入射分光器用の球面回折格子では、光子溝間隔を著しい不等間隔にする必要があり、機械刻線による回折格子と同一の結像面を有するホログラフィック回折格子の設計製作は不可能とされていた。われわれは、露光々学系に球面鏡を挿入した非球面波露光法を適用し、従来の球面波露光法では製作できなかった+/-25mmの左右両端で+/-約200本/mm溝本数が変化したラミナー型ホログラフィック回折格子を製作した。本論文では不等間隔溝パラメータ設計法、ラミナー型溝形状の加工法、C-K
線などを用いた分解能テスト、放射光源を用いた絶対回折効率の測定結果について、機械刻線回折格子と比較しながら述べる。
山嵜 孝; Gullikson, E. M.*; 宮田 登*; 小池 雅人; 原田 善寿*; Mrowka, S.*; Kleineberg, U.*; Underwood, J. H.*; 柳原 美広*; 佐野 一雄*
Applied Optics, 38(19), p.4001 - 4003, 1999/07
被引用回数：22 パーセンタイル：70.23(Optics)本論文ではレーザープラズマ分光等に用いられる平面結像型斜入射球面回折格子分光器用のラミナ型ホログラフィック回折格子を非球面波露光法により設計、製作、評価した例について述べている。製作した中心溝本数1200本/mmの回折格子は
25mmの両端で約200本/mm溝本数が変化している。これと従来の機械刻線型とを比較すべく、スペクトル分布測定を東北大科研の平面結像型分光器を用いて4.4nm輝線で行ったところ、1次光の半値幅は約0.4nmと機械刻線型の約3倍であった。ただし、回折格子の溝間隔等の微妙な違いが影響している可能性がある。また、絶対回折効率測定をLBNL/ALSの反射率計を用いて4.5nm-22nmの範囲で行い、1次光強度に対する2次光の相対強度が機械刻線型の120%-10%に対しラミナ型が13%-20%と、2次光の相対強度が総じて低くするという結果を得た。
武田 全康; 山崎 大; 曽山 和彦; 林田 洋寿; 藤 健太郎; 山岸 秀志*; 片桐 政樹*; 坂佐井 馨; 丸山 龍治; 水沢 多鶴子*; et al.
no journal, ,
A new polarized neutron reflectometer (SHARAKU) was installed at the beam line 17 (BL17) of MLF as the second neutron reflectometer in J-PARC. This reflectometer was designed for a variety of surface science applications except the free surface and interface investigation. Therefore, this reflectometer has the capability of performing full polarization analysis, grazing incidence small-angle neutron scattering (GISANS), and the grazing incidence diffraction (GID) measurements. Four kinds of detectors are employed to cover a wide q-range with a proper q-resolution. One is a point detector, and the other three are two-dimensional position-sensitive-detectors. A polarizer and analyzer both of which consist of Fe/Si polarizing supermirrors and two-coil flippers are used for the polarization analysis. We will report the outline design specification, and the basic performance of this new reflectometer.
武田 全康; 山崎 大; 曽山 和彦; 林田 洋寿; 藤 健太郎; 山岸 秀志*; 片桐 政樹*; 坂佐井 馨; 丸山 龍治; 水沢 多鶴子*; et al.
no journal, ,
A new polarized neutron reflectometer (SHARAKU) was installed at the beam line 17 (BL17) of the Material and Life Science Experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC). The user program of this reflectometer has been already started in February 2012. We will report the outline design specification, and the basic performance of this new reflectometer.
武田 全康; 山崎 大; 曽山 和彦; 藤 健太郎; 山岸 秀志*; 片桐 政樹*; 坂佐井 馨; 水沢 多鶴子*; 宮田 登*; 笠井 聡*; et al.
no journal, ,
SHARAKU is the second neutron reflectometer of MLF, and open to the general users from the 2011B user beamtime period. This reflectometer focuses on solid-state physics, particularly on magnetism in contrast with the first neutron reflectometer (SOPHIA) whose main subject is the soft matter science with capability of free surface and interface investigation. Thus this reflectometer was designed as the polarized neutron reflectometer with the vertical sample geometry, and is capable of the full neutron spin polarization analysis of the reflected neutrons using the Fe/Si supermirror polarizer and analyzer. Current status of SHARAKU will be reported in the symposium.
山崎 大; 曽山 和彦; 宮田 登*; 笠井 聡*; 阿久津 和宏*; 花島 隆泰*; 久保田 正人; 青木 裕之; 鈴木 淳市*; 藤 健太郎; et al.
no journal, ,
試料垂直型偏極中性子反射率計「SHARAKU」では、薄膜試料の表面や界面で起こるoff-specular反射、Grazing angle SANSの測定を目指して2次元MWPC中性子検出器を整備している。MWPCは、0.5mmピッチのワイヤーによる個別読み出し方式を採用し、各々の信号ラインにASD-ASICを配置することで、高速・高効率を実現している。本実験では、BL17ビームラインにおいて、Ni/Ti多層膜を試料として中性子反射率実験を行った。その結果、1.8mmの空間分解能を確認し、qz-qx方向について明瞭なシグナルを記録した。本報告では、2次元MWPCの特性とその中性子反射率測定への応用について述べる。
杉山 一生*; 齊藤 正裕*; 宮田 登*; 花島 隆泰*; 阿久津 和宏*; 青木 靖仁*; 大塚 祐二*; 武田 全康; 清水 亮太*; 一杉 太郎*
no journal, ,
固体電解質/電極界面近傍に生じる空間電荷層は、系全体の物性に大きな影響を及ぼすことから、空間電荷層内部における各元素の濃度分布を明らかにすることは極めて重要である。しかしながら、空間電荷層におけるLi濃度分布を直接的かつ定量的に測定した報告はなかった。そこで本研究では、固体電解質に電圧印加(5V)しつつ、ラザフォード後方散乱(RBS), 核反応分析法(NRA)、そして、中性子反射率測定を行い、nmから数十
mまでの広いレンジで固体電解質/電極界面近傍のLi濃度分布を明らかにすることに成功した。
曽山 和彦; 青木 裕之; 山崎 大; 宮田 登*; 阿久津 和宏*; 花島 隆泰*; 笠井 聡*; 鈴木 淳市*
no journal, ,
SHARAKU is a neutron reflectometer using polarized neutron pulses in Materials and Life Science Experiment Facility (MLF) in Japan Proton Accelerator Research Complex (J-PARC). A polarization reflectometry can probe not only a nanometric layered structure with a contrast of an atomic neutron scattering length but also of a magnetic scattering length; therefore, SHARAKU is a powerful tool to analyze a magnetic structure in a magnetic thin film. SHARAKU has large flexibility of the sample environment. In addition to a 1-T magnet and a 4-K refrigerator for the magnetic samples, we have recently developed a liquid immersion cell and atmosphere control chamber for soft-matters. The user experimental programs have been carried out in various fields such as solid state physics, polymer physics, and electro-chemistry.
丸山 龍治; 山崎 大; 青木 裕之; 阿久津 和宏*; 花島 隆泰*; 宮田 登*; 曽山 和彦; Bigault, T.*; Saerbeck, T.*; Courtois, P.*
no journal, ,
The polarized neutron off-specular scattering measurement of Fe/Ge periodic multilayers revealed that the ferromagnetic (FM) interlayer exchange coupling between neighboring Fe layers grew with decreasing Ge thickness less than 2 nm. The FM interlayer exchange coupling observed here contributed to the presence of the saturation magnetization comparable to the bulk and to smaller coercivity and larger initial permeability than the multilayer without the FM interlayer exchange coupling. This offers a possibility to keep the spontaneous magnetization for the multilayer with a thin bilayer thickness and hence to increase the bandwidth of the polarizing supermirror. We proposed a modified layer sequence of the neutron polarizing supermirror, where the minimum Fe thickness was set to 3.5 nm, whereas the Ge thickness was reduced. A performance test of the neutron polarizing supermirror showed that the FM interlayer exchange coupling contributed to the presence of the magnetization comparable to the bulk and resulted in a marked enhancement in the m-value larger than 6.
