The angular distribution of secondary ions is one of the essential elements for development of three-dimensional (3D) shave-off SIMS. The magnification lens system in the 3D shave-off SIMS was designed and assembled based on the detection position of the detector. However, shave-off condition of high incidence energy (30 keV) and angle of incidence (87 degrees), we simulated the angular distribution of sputtered particles using the SDTrimSP program and compared the results with the previous shave-off experimental data. Even unusual the shave-off beam, the SDTrimSP simulation results showed a good agreement and a similar tendency with the experimental data. SDTrimSP simulation is expected to be useful in obtaining the sputtered particle information for development and instrumentation of 3D shave-off SIMS.

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Secondary ion mass spectrometry (SIMS) has some disadvantages including degradation in depth resolution depending on the depth which are difficult to resolve. To address these disadvantages, we have previously developed shave-off SIMS and achieved two-dimensional mapping. In this study, we designed the appropriate secondary ion optical system by simulation to achieve three-dimensional shave-off SIMS. We developed new optical parts and evaluated the abilities of the designed secondary ion optical system. We acquired the following abilities of the secondary ion optical system: magnification ratio 1.6 × 10², Z-axial resolution 0.70 □m, and transmission > 0.1%.

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TOF-SIMS の最大の特長は高空間分解能を活かしたイメージングにあり，非常に高精細で高感度な元素や分子種のイメージを提供できる唯一の表面分析手法である．しかしながら，汎用の TOF-SIMS 装置は，平坦な試料を前提としており，ワイヤや球など湾曲した試料では，非常に限られた一部の領域しか観察することができない．そのため，これまでワイヤや球状試料表面に存在する成分の正確な分布を議論することが困難であった．この問題を解決するために，いくつかの方法が提案されているが，いずれも欠点があった．そこで，著者らは湾曲した試料全面のイメージングを目的とした試料ホルダーの開発を行ってきた．その結果，従来に比べ， 観察可能な領域を大きく拡大することに成功した．本稿では，曲面観察用試料ホルダーの詳細と，ホルダーの評価を行った結果について議論した後，応用事例を紹介する．

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We have investigated the Auger depth profiling analysis of HfO₂/Si by the glancing-angle ion beam sputtering method at an incident angle of 7 degree from the sample surface with argon ion beam. The depth resolutions of the O KLL interface profiles were 0.9 nm and 1.5 nm, at the ion-beam acceleration voltage of 2.0 kV and 3.0 kV respectively, which were better than the depth resolutions at a commonly-used incident angle of 51 degree. However, the ion-beam-induced reduction of HfO₂ was not suppressed by the glancing-angle ion beam sputtering at the ion acceleration voltage of 0.5 kV, which is expected to be the lowest damage sputtering condition in this study. The reduction of HfO₂ due to preferential sputtering of oxygen was observed by the intensity ratio of O KLL and Hf NVV depth profiles. It was found that the ratio of preferential sputtering depends on the ion incidence angle and the ion acceleration voltage. Under the glancing-angle condition, the ratio of preferential sputtering greatly depended on the ion accelerating voltage, and it was found that the lower the ion acceleration voltage is, the easier it is for O to be sputtered than Hf. On the other hand, under the commonly-used incident angle conditions, the ratio of preferential sputtering did not depend much on the ion acceleration voltage. The dependency of the ratio of preferential sputtering on the ion incidence angle can be explained by the difference in sputtering models depending on the ion incidence angle. It was found that the O KLL depth profiles showed partial recovery of the oxygen intensity near the interface of HfO₂/Si, which can be related to oxygen generated by the ion-beam-induced decomposition of the diffusion layer at the interface. In addition, the glancing-angle ion beam enables the reduction of the effect of recoil implantation of Hf atoms into the Si substrate.

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