【表面と真空 (Vacuum and Surface Science)】は，2018年4月の日本表面科学会と日本真空学会の合併により設立された公益社団法人 日本表面真空学会が出版する学術論文誌です。設立に先立つ2018年1月に創刊された新しいジャーナルになります。前身誌は日本真空学会の【Journal of the Vacuum Society of Japan】と日本表面科学会の【表面科学】になり，双方の記事種を踏襲し，その上で新たな分野への展開を目指しています。巻号は，歴史のより長い【Journal of the Vacuum Society of Japan】の巻数を引き継ぎ，第61巻からの創刊となります。
We introduce the results of in situ observation of the surface and the solid-liquid interface of calcium carbonate in atomic-level by frequency modulation atomic force microscopy (FM-AFM) in the presence of additives. We have found that the calcite surface transformed into the aragonite structure by the cooperative effect of magnesium and a hydrophilic polypeptide. Furthermore, high-resolution imaging of solid-liquid interface revealed that these additives did not adsorb on the calcite surface but significantly changed the hydration structure in the vicinity of the surface. Especially magnesium ions contribute to change the hydration structure due to their hydrophilicity.
Room-temperature wafer bonding can realize new electronic devices, power devices, optical devices, and microelectromechanical systems. Atomic diffusion bonding (ADB) of wafers is a promising process to achieve room-temperature wafer bonding : thin metal films are fabricated on two flat wafer surfaces using sputter deposition, followed by bonding of the two films on the wafers in vacuum. Any mirror-polished wafer including glass can be bonded using ADB. Recently we demonstrated ADB of wafers at room temperature using oxide films and nitride films. Incident light can pass through transparent wafers bonded with oxide films without reduction in intensity. Moreover, the electrical conductivity of the bonded oxide films and nitride films is negligible. These properties are useful to produce new optical or electrical devices. This paper assesses the technical potential and current status of ADB.
高城 拓也, 秋山 了太, I. A. Kibirev, A. V. Matetskiy, 中西 亮介, 佐藤 瞬亮, 深澤 拓朗, 佐々木 泰祐, 遠山 晴子, 樋渡 功太, A. V. Zotov, A. A. Saranin, 平原 徹, 長谷川 修司
Under the competition of ferromagnetic interaction and Dzyaloshinskii-Moriya interaction, magnetic vortices in real-space, skyrmions, can be induced on a topological insulator (TI), which reflects the chiral spin structure on the gapped Dirac cone in the momentum space. Here, we observe skyrmions emerge on surfaces of two self-assembled ferromagnetic TI layers, Mn(Bi1－xSbx)2Te4, separated by a spacer of non-magnetic TI layer, (Bi1－xSbx)2Te3, through topological Hall effect (THE) by tuning the Fermi level with optimizing the Bi/Sb ratio. By the spacer-thickness-dependence of the magnitude of THE, we find that the moderate coupling of surface states between the top and bottom Mn(Bi1－xSbx)2Te4 layers is essentially important for inducing and stabilizing skyrmions. Moreover, the highly-ordered Mn atoms in the Mn(Bi1－xSbx)2Te4 lead to a strong exchange interaction therein, making skyrmions “soft magnetic”. This would open an avenue toward a topologically robust easy-rewritable novel magnetic memory for spintronics.
We investigate the factors that degrade the conversion efficiency in the crystalline silicon heterojunction (SHJ) solar cell using hard X-ray photoelectron spectroscopy (HAXPES) and the potential of new materials for the carrier selective contact (CSC). Regarding the emerging transparent conductive oxide film (TCO) used in the SHJ solar cell, the hydrogenated indium oxide (IO:H) with high carrier mobility forms an oxide layer at the IO:H/substrate interface revealed by the evaluation of chemical bonding states by HAXPES, resulting in increasing the contact resistance. Moreover, the IO:H is reduced from the catalyst in the silver electrode paste, and silver oxide tends to form at the electrode/IO:H interface. In addition, the role of MoS2, a two-dimensional layered material, as a CSC layer was investigated, found that and MoS2 layer works as an electron selective layer for n-type Si substrate using angle-resolved HAPXES band bending evaluation.
We have recently reported a new two-dimensional material of boron monosulfide (BS) nanosheet. It was produced by the mechanical exfoliation of rhombohedral boron monosulfide (r-BS) synthesized by heating the mixture of amorphous boron and sulfur at 1873 K and 5.5 GPa. Experimental characterizations and density functional theory calculations revealed tunable band-gap of BS nanosheets as much as approximately 1.0 eV. These results are introduced in detail.