【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。
This article provides an overview of the authors' activity on organic secondary ion mass spectrometry (organic SIMS) using ionic liquids. Ionic liquids, i.e., molten salts with a melting point less than 100℃, have negligible vapor pressures, so that they are compatible with ultra-high vacuum. They are divided into two groups : aprotic ionic liquids and protic ionic liquids. Both ionic liquids were tested as liquid matrices and as primary ion beams in organic SIMS. Protic ionic liquids proved to be effective to enhance molecular secondary ion intensities, whereas aprotic ionic liquids were not useful. Among ionic liquids, alkylammonium titrates such as propylammonium nitrate will be most promising for organic SIMS.
There have been a lot of artificial superhydrophobic surfaces, however, those are difficult to use in daily purposes because of their brittle, stiff and breakable properties. We have been reported fabrication of superhydrophobic microstructured vulcanized rubber surfaces by using silicon microstructures as mold during their vulcanization process. Furthermore, the arrangement of microstructures could be repeatedly transformed from a hexagonal to linear patterns by elongations and superhydrophobicity was kept during elongation process. In this report, we prepared other type of superhydrophobic microstructured vulcanized rubber surfaces, which can be changed surface wettability by stretching. The superhydrophobic microstructured vulcanized rubber surfaces were prepared by using a silicon microstructures as mold. After observation of surface structures and wettability by laser microscopy and water contact angle analyzer, we took high-speed photography of water droplets felled to the rubber surfaces with different elongation rates, and theoretically discussed the differences of water behaviors.
Si films including hierarchical nanodot structures were developed using ultrathin SiO2 films. Scattering bodies with various size scales are expected to scatter phonons with various wavelengths. This idea is important for reduction of thermal conductivity because phonon, that is boson, with various wavelengths, can contribute to the heat transport. Here, in Si films including Si nanodot structures, the nanodots with various sizes reduced the thermal conductivity effectively in addition to increase of dopant activation rates. Furthermore, highly-doped Si films including Ge nanodots that have atomic scale and nanoscale phonon scattering bodies exhibited drastically-reduced thermal conductivity. This drastic reduction of thermal conductivity came from hierarchical structures that include nanodot structures working as strong phonon scattering bodies. This gives the guideline of control of phonon and carrier transport using nanostructures for high performance thermoelectric materials.
Semiconductor cleaning is a very important process in integrated circuit manufacturing, and the removal of high dose ion implanted photoresist is a big challenge in semiconductor cleaning owing to their carbonized crust layer generated on and near the surface of the photoresist layer. Microbubbles are a promising candidate in single wafer spin cleaning process for the removal of the crust generated photoresist without any substrate loss. And the bubbles are gas bodies less than 50 micrometer in diameter and shrink underwater due to the rapid dissolution of the interior gas. It has been demonstrated that the bubbles can generate free radicals during the collapsing process under water through the dispersion of the elevated energy accumulated as the surface electricity during the collapsing process of microbubble. In this article the author introduces the fundamental properties of microbubble and their several examples relating to semiconductor cleaning.