Characterization of Porous Structures in Advanced Low-k Films with Thin TaN Layers Using Monoenergetic Positron Beams
Characterization of Porous Structures in Advanced Low-k Films with Thin TaN Layers Using Monoenergetic Positron Beams
复制标题
使用单能正电子束表征具有薄 TaN 层的先进低 k 薄膜中的多孔结构
DOI：
10.7567/jjap.52.106501
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发表时间：
2013
影响因子：
1.5
通讯作者：
R. Suzuki
中科院分区：
文献类型：
--
作者：
A. Uedono;P. Verdonck;A. Delabie;J. Swerts;T. Witters;T. Conard;M. Baklanov;S. Elshocht;N. Oshima;R. Suzuki
采用单能正电子束对等离子体增强化学气相沉积制备的先进低k（ALK）薄膜的孔径及其深度分布进行了测定。对沉积TaN原子层前后ALK薄膜的湮没γ射线能量分布和正电子寿命谱的测量表明，Ta原子扩散到了薄膜中。结果，平均孔径减小，较大孔的数量优先减少。从电子动量分布的测量中，我们发现，几乎所有的孔的内壁被钽覆盖的ALK膜没有预处理前的TaN沉积。然而，通过使用Ar/N2或Ar/H2气体混合物的等离子体处理来抑制Ta向膜中的渗透，其中Ar/N2-等离子体处理比Ar/H2-等离子体处理更有效地阻止Ta扩散。通过这项工作，我们已经证明，单能正电子束是一个强大的工具，用于表征加盖多孔膜和金属原子的孔捕获。
Pore sizes and their depth distributions in advanced low-k (ALK) films fabricated using plasma-enhanced chemical vapor deposition were determined using monoenergetic positron beams. The measurement of the energy distributions of annihilation γ-rays and the positron lifetime spectra of the ALK films before and after thin TaN atomic layer deposition showed that Ta atoms diffused into the films. As a result, mean pore size decreased, with the number of larger pores decreasing preferentially. From the measurements of the electron momentum distribution, we found that almost all the inner walls of pores were covered by Ta for the ALK film without pretreatment before TaN deposition. The penetration of Ta into the film, however, was suppressed by plasma treatment using an Ar/N2 or Ar/H2 gas mixture, where the Ar/N2-plasma treatment more effectively blocked Ta diffusion than the Ar/H2-plasma treatment. Through this work, we have demonstrated that monoenergetic positron beams are a powerful tool for characterizing capped porous films and the trapping of metallic atoms by pores.