Preparation of nanocrystalline HfNx films as a thin barrier for through-Si via interconnects in three-dimensional integration

作者：Takeyama Mayumi B^*; Sato Masaru; Aoyagi Eiji; Noya Atsushi

来源：Japanese Journal of Applied Physics, 2014, 53(2): 02BC05.

DOI：10.7567/JJAP.53.02BC05

We propose a barrier material applicable to the through-Si via (TSV), a key technology for the three-dimensional stacked integration, from the point of view of materials science, including excellent thermal and chemical stability, low resistivity, and conformability to thin-film formation. We examine N-rich HfNx films consisting of nanocrystalline grains as candidate barrier materials. The HfNx film consisting of a HfN single phase without contaminants shows excellent phase stability and low resistivity. The barrier in the Cu/HfNx/SiO2/Si model configuration shows excellent barrier properties with little structural change and without excess solid-phase reactions and/or diffusion due to annealing. A 5-nm-thick thin barrier applicable to TSV downsizing in the future is thus effective in satisfying the fundamental requirements of a good needed barrier, stemming from the low-temperature process of TSV technology.

• 出版日期2014-2