Study on Nano-inprocess measurement of CMP defects on SiO2 filmed wafer surface

SiO2薄膜晶圆表面CMP缺陷的纳米在线测量研究

• 批准号: 12450060
• 负责人: MIYOSHI Takashi
• 金额: $ 7.87万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450060/
• 关键词: Surface defect; Nano-inprocess measurement; Laser applied measurement; CMP process; SiO2 thin film; Silicon wafer; Laser light scattering; Semiconductor

Light scattering measurements are performed for defects on SiO_2 filmed wafer such as microscratches and PSL (Poly Styrene Latex) particles using the automated 3-D light scattering measurement system originally developed. These microscratches made by FIB (focused ion beam) process are used as equivalent of CMP (Chemical Mechanical Polishing) scratch defects. Several experiments are carried out with these defects that have different sizes.Main results of this study are summarized as follows,(1) CMP defect detection schemes by using numerical analysis based on BEM (Boundary Element Method) have been proposed. Depths and widths of defect are separately obtained by the scattered light intensity distribution. It is shown that the killer defects can be easily categorized in the defect classification map.(2) microscratchs with depth of 30 to 120 nm and width of 250 to 600 nm are made on SiO_2 film surface (film thickness, 0.5 μm) by FIB process. The scattering light from these defects has hig … More h intensity not in the normal but in the backward region for Brewster's angle (55.6 degree) incidence. Besides, the scattering light intensity with s-polarized illumination is higher than with p-polarized one.(3) However, for p-polarized illumination, scattered light from scratches changes sensitively with only 30 nm depth differences of them. The deeper the depth of a scratch is the higher the scattered light intensity is detected. Therefore, it is possible to measureme depth of a scratch with high accuracy based on the scattering light intensity.(4) Scattered light intensity from scratches is not proportional to width of them. When the aspect ratio of depth to width is larger than 3, it is likely that the wider the width becomes, the lower the scattering light intensity is detected.(5) PSL (Poly Styrene Latex) particles on SiO_2 filmed wafer scatters s-polarized light sensitively. Even if the size difference of particles is of less than 100 nm, both the scattering patterns are distinguishable. Especially, the intensities in forward scattering for the size difference is remarkable, for example, the scattering intensity for the particle size of 200 nm is 5.5 times as high as 100 nm.(6) The distribution of the scattering intensity to the scattering angle has a peak at 55 degree for a PSL particle and 0 degree for a microscratch. This result makes it possible to distinguish both the defects. Less

利用自行研制的自动化三维光散射测量系统，对SiO_2薄膜硅片表面的微划痕、聚苯乙烯乳胶颗粒等缺陷进行了光散射测量。这些由FIB（聚焦离子束）工艺制造的微划痕被用作CMP（化学机械抛光）划痕缺陷的等效物。主要研究结果如下：（1）提出了基于边界元法（BEM）的CMP缺陷检测方法。由散射光强度分布分别得到缺陷的深度和宽度。结果表明，杀手缺陷可以很容易地分类在缺陷分类图。(2)用FIB工艺在SiO_2膜（膜厚0.5 μm）表面形成深30 ~ 120 nm、宽250 ~ 600 nm的微划痕。这些缺陷的散射光具有很高的强度， ...更多信息 h强度不是在正常区域，而是在布鲁斯特角（55.6度）入射的后向区域。此外，散射光强度与s偏振照明高于与p偏振。(3)然而，对于p偏振照明，来自划痕的散射光变化敏感，它们的深度差仅为30 nm。划痕的深度越深，检测到的散射光强度越高。因此，可以基于散射光强度以高精度测量划痕的深度。(4)划痕的散射光强度与划痕的宽度不成正比。当深度与宽度的纵横比大于3时，可能宽度变得越宽，检测到的散射光强度越低。(5)SiO_2薄膜晶片上的PSL（Poly Styrene Latex）粒子对s偏振光具有敏感的散射作用。即使颗粒的尺寸差小于100 nm，两种散射图案也是可区分的。特别是，对于尺寸差异的前向散射强度是显著的，例如，对于200 nm的颗粒尺寸的散射强度是100 nm的5.5倍。(6)散射强度对散射角的分布对于PSL颗粒在55度处具有峰值，对于微划痕在0度处具有峰值。该结果使得可以区分这两种缺陷。少

项目成果

Taeho Ha, 三好隆志, 高谷裕浩, 高橋哲, 新田大輔: "光敵乱によるCMP加工表面薄膜欠陥計測に関する研究(第2報)-表面マイクロスクラッチの散乱特性-"2002年度精密工学会春季大会学術講演会講演論文集. 東工大(発表予定). (2002)

Taeho Ha、Takashi Miyoshi、Hirohiro Takatani、Satoshi Takahashi、Daisuke Nitta：“利用光学扰动对 CMP 加工表面进行薄膜缺陷测量的研究（第二次报告） - 表面微划痕的散射特性 -” 2002 年日本精密工程学会春季。东京工业大学学术会议论文集（即将发表）（2002 年）。

吉崎大輔,三好隆志,高谷裕浩,高橋哲: "暗視野輪帯光学系を用いたSiウエハ加工表面欠陥計測に関する研究(第2報)-高感度検出法の検討-"2001年度精密工学会春季大会学術講演会講演論文集. (発表予定). (2001)

Daisuke Yoshizaki、Takashi Miyoshi、Hirohiro Takatani、Satoshi Takahashi：“利用暗场环形光学系统进行硅晶片加工表面缺陷测量的研究（第2次报告）-高灵敏度检测方法的检验-”2001年精密工程学会论文集春季学术会议（预定报告）（2001）。

Taeho HA, Takashi MIYOSHI, Yasuhiro TAKAYA, Satoru TAKAHASHI: "Development of Automatic Light Scattering Measurement System for Si Wafer Microdefects"Proceedings of The 4th International Symposium on Advances in Abrasive Technology-Intelligent Machining o

Taeho HA、Takashi MIYOSHI、Yasuhiro TAKAYA、Satoru TAKAHASHI：《硅片微缺陷自动光散射测量系统的开发》第四届国际磨料技术进展-智能加工研讨会论文集

新田大輔, 三好隆志, 高谷裕浩, 高橋哲, Taeho Ha: "光敵乱によるCMP加工表面薄膜欠陥計測に関する研究(第3報)-付着異物の散乱特性-"2002年度精密工学会春季大会学術講演会講演論文集. 東工大(発表予定). (2002)

Daisuke Nitta、Takashi Miyoshi、Hirohiro Takatani、Satoshi Takahashi、Taeho Ha：“利用光学扰动对 CMP 加工表面进行薄膜缺陷测量的研究（第 3 次报告）- 附着异物的散射特性 -” 2002 年精密工程学会春季会议收集东京工业大学学术会议论文（待提交）（2002 年）。

新田大輔, Taeho Ha, 三好隆志, 高谷裕浩, 高橋哲: "Siウエハ酸化膜欠陥検出における光散乱偏光特性"2001年度砥粒加工学会学術講演会講演論文集. 金沢工大. 263-264 (2001)

Daisuke Nitta、Taeho Ha、Takashi Miyoshi、Hirohiro Takatani、Satoshi Takahashi：“Si 晶片氧化膜缺陷检测中的光散射偏振特性”，金泽工业学院 2001 年学术会议论文集（2001 年）。 ）