Development of a Technique for Detecting Ultra Low Density of Surface Impurities by Means of Multiphoton Resonance Ionization

多光子共振电离检测超低密度表面杂质技术的开发

• 批准号: 63850006
• 负责人: MORITA Kenji
• 金额: $ 4.29万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63850006/
• 关键词: multiphoton resonance ionization; time of Flight technique; energy distribution; ion impact desorption; recoil-implantation; monoatomic layer impurity; sub-ppm; スパッタリング

Goal of this project is to develop a technique for detecting ulta low density of surface impurities by means of multiphoton resonance ionization spectroscopy.In 1989, we have performed following tasks concerning with this project. (1) Development of multiphoton resonance ionization spectroscopy system A multiphoton resonance ionization spectroscopy system has been developed and combined with the time of flight technique for detecting of post-ionized particles. The multiphoton resonance ionization used here is based on that one exciting laser radiation excites an atom from the ground state to an excited state and another ionizing laser radiation ionizes from the excited state to the continuum. The resonance wavelengths of exciting laser radiation for ionization of Ni atoms are found to be 2290.38A^^ﾟ, 2320.46A^^ﾟ and 2346.00A^^ﾟ and the resonance wavelength for Fe atoms is found to be 2166.75A^^ﾟ using metal atomic beams from vapor surfaces. (2) Measurement of the energy distribution of … More Ni atoms sputtered from Ni targets The system developed here has been applied for measuring the energy distribution of neutral Ni atoms sputtered from Ni targets by 5 keV Ar^+ ions. It is found that the energy distribution of sputtered Ni atoms is similar to the Thompson distribution and the peak energy is 0.7-0.8 eV. The low peak-energy, corresponding to the low surface binding energy, is attributed to a carbide phase at the nickel surface. The efficiency for resonance ionization in this case is confirmed to be saturated to 100%. (3) Characterization of Si(111)ROO<3>xROO<3> -Ag surfaces by means of LEED-AES-RBS techniques It is found by means of the RBS technique that the Ag coverage at the Si(111)ROO<3>xROO<3> -Ag surfaces produced by annealing Ag deposited Si(111) specimens ranges from 0.62 to 0.82 and a part of deposited Ag atoms diffuse into the Si substrate, for the ROO<3>xROO<3> LEED patterns observed clearly similarly with different five specimens. It is concluded from the fact that the Ag coverage at the Si(111)ROO<3>xROO<3> -Ag surface is nominally unity. (4) Ion impact desorption of Ag from Si(111)ROO<3>xROO<3> -Ag surface The concentration decay of Ag atoms at the Si(111)ROO<3>xROO<3> -Ag surface induced by keV Ar^+ ions has been measured by means of LEED-AES-RBS techniques, It is found that the desorption cross-section of Ag atoms at 5 key is determined to be 8.0X10^<-16> cm^2 and the binding energy of Ag atom at the Si(111)ROO<3>xROO<3> -Ag surface is estimated to be 0.6 eV from the experimental recoil-implantation cross-section. Less

该项目的目标是开发一种通过多光子共振电离光谱检测超低密度表面杂质的技术。1989年，我们完成了与该项目相关的以下任务。 (1)多光子共振电离光谱系统的开发 开发了多光子共振电离光谱系统，并将其与飞行时间技术相结合，用于检测电离后粒子。这里使用的多光子共振电离是基于一种激发激光辐射将原子从基态激发到激发态，而另一种电离激光辐射将原子从激发态电离到连续谱。使用来自蒸气表面的金属原子束，发现用于电离 Ni 原子的激发激光辐射的共振波长为 2290.38A^^ﾟ、2320.46A^^ﾟ 和 2346.00A^^ﾟ，并且发现 Fe 原子的共振波长为 2166.75A^^ﾟ。 (2) Ni靶溅射Ni原子能量分布的测量本文开发的系统已应用于测量5 keV Ar^+离子从Ni靶溅射的中性Ni原子的能量分布。发现溅射Ni原子的能量分布与Thompson分布相似，峰值能量为0.7-0.8 eV。与低表面结合能相对应的低峰值能量归因于镍表面的碳化物相。确认此时的共振电离效率饱和至100%。 (3)利用LEED-AES-RBS技术表征Si(111)ROO 3 xROO 3 -Ag表面通过RBS技术发现，对Ag沉积的Si(111)样品进行退火产生的Si(111)ROO 3 xROO 3 -Ag表面的Ag覆盖范围为0.62至0.82，并且部分沉积Ag 对于用不同的五个样本清楚地观察到的ROO 3 xROO 3 LEED图案，原子扩散到Si衬底中。从Si(111)ROO 3 xROO 3 -Ag表面处的Ag覆盖率名义上一致的事实可以得出结论。 (4)Ag从Si(111)ROO 3 xROO 3 -Ag表面的离子冲击脱附采用LEED-AES-RBS技术测量了keV Ar^+离子引起的Si(111)ROO 3 xROO 3 -Ag表面Ag原子的浓度衰减，发现Ag原子在5键处的脱附截面确定为 8.0X10^-16cm^2并且从实验反冲注入截面估计Si(111)ROO3xROO3-Ag表面处Ag原子的结合能为0.6eV。较少的

项目成果

田中伸治: "Ion Impact Desorption of Ag from Si(111)(√<3>×√<3>)R30°-Ag Surfaces" Nuclear Instruments and Methods B.

Shinji Tanaka：“Ag 从 Si(111)(√<3>×√<3>)R30°-Ag 表面离子撞击脱附”核仪器和方法 B.

橋本洋一: Muclear Instruments and Methods B. 33. 515-518 (1988)

Yoichi Hashimoto：Muclear 仪器和方法 B. 33. 515-518 (1988)

田中伸治: "Ion Impact Desorption of Ag from Si(111)(√<3>×√<3>) R30°-Ag Surfaces" Nuclear Instruments and Methods B.

Shinji Tanaka：“Ag 从 Si(111)(√<3>×√<3>) R30°-Ag 表面离子撞击脱附”核仪器和方法 B.

井上雅彦: "Characterization of Si(111)√<3>×√<3>-Ag Surfaces by means of LEED-AES-RBS Techniques" Surface Science.

Masahiko Inoue：“通过 LEED-AES-RBS 技术表征 Si(111)√<3>×√<3>-Ag 表面”表面科学。

井上雅彦: "Characterization of Si(111)√<3>×√<3>-Ag.Surfaces by means of LEED-AES-RBS Techniques" Surface Science.

Masahiko Inoue：“通过 LEED-AES-RBS 技术表征 Si(111)√<3>×√<3>-Ag.Surfaces”表面科学。