Improvement of thermal stability of via resistance in dual damascene copper interconnection
Improvement of thermal stability of via resistance in dual damascene copper interconnection
复制标题
双镶嵌铜互连中通孔电阻热稳定性的改善
DOI：
10.1109/iedm.2000.904273
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
K. Hinode
中科院分区：
文献类型：
--
作者：
T. Oshima;T. Tamaru;K. Ohmori;H. Aoki;H. Ashihara;Tatsuyuki Saito;H. Yamaguchi;M. Miyauchi;K. Torii;J. Murata;A. Satoh;H. Miyazaki;K. Hinode
研究了多层双金属Cu互连中通孔电阻的热稳定性。过孔电阻的稳定性主要取决于过孔尺寸、过孔密度和连接铜线的宽度。应力引起的空洞化引起了通孔电阻的显著变化。为了避免空洞失效，优化电镀（EP）-Cu沉积后的热处理对于Cu膜的稳定性和阻挡层与Cu的粘附是必要的。铜导线和层间介质（ILD）之间的热应力平衡也是重要的，以抑制过孔退化。具有较低应力和较低杨氏模量的ILD膜（例如FSG）的双MEMS结构可以为过孔电阻的稳定性提供更宽的工艺窗口。
Thermal stability of via resistance in the multilevel dual damascene Cu interconnection was investigated. The via resistance stability strongly depends on via size, via density and width of connecting Cu wires. The significant via-resistance shift was introduced by stress-induced voiding. To avoid the voiding failure, optimization of heat treatments after electroplating (EP)-Cu deposition are necessary for both stability of Cu films and adhesion of barrier layer with Cu. Thermal stress balance between Cu wires and inter-level-dielectric (ILD) is also important to suppress the via degradation. The dual damascene structure with lower-stress and lower-Young's modulus ILD films such as FSG can provide wider process windows for the stability of the via resistance.