Ti稳定N的三元Cu合金薄膜

N-Containing Ternary Cu Alloy Films Stabilized by Ti

由于铜与氮不能生成稳定的化合物,使得渗氮的方法不能用于提高铜的表面硬度。通过在Cu中添加能够稳定N的合金元素Ti,探索提高Cu表面硬度的有效方式。用磁控溅射法在Si（100）基体上制备不同Ti、N含量的Cu膜,对三元Cu合金膜进行微结构、硬度以及电阻率的分析。结果表明,加入Ti可以使N以钛氮化合物的形式稳定存在于Cu薄膜中,合金薄膜的硬度比纯Cu膜（～3.5 GPa）有了很大的提高,特别是Cu80.2Ti9.8N10.0薄膜在400℃/1 h退火后硬度依然为5.4 GPa。Ti、N含量高的Cu81.2Ti9.9N8.9薄膜的电阻率（～660μΩ·cm）比Cu88.5Ti4.3N7.2薄膜（～123μΩ·cm）高很多,但两薄膜的硬度却都约为5.2 GPa,所以,薄膜中并不是Ti、N含量越高性能越好,因此应该合理控制各组元含量。

Since copper can not form stable compounds with nitrogen, the conventional surface hardening method can not be used to improve the surface hardness of copper. An effective method of improving the surface hardness of copper was explored by adding Ti which could stabilize N in Cu alloy films. The Cu alloy films containing different contents of Ti and N were deposited onto the Si（100） substrates by magnetron sputtering and their microstructure, hardness and resistivity were analyzed. The results suggest that the addition of Ti leads to stable N in Cu alloy films in the form of Ti-N compounds, and the hardness of the alloy films is improved compared with that of pure Cu film（～3.5 GPa）. Particularly, the hardness of Cu80.2Ti9.8N10.0 film is still 5.4 GPa even after annealing at 400 ℃ for 1 h. The resistivity of the Cu81.2Ti9.9N8.9 film（～660 μΩ·cm） with large contents of Ti and N is much higher than that of Cu88.5Ti4.3N7.2 film（～123 μΩ·cm）, but their hardness is almost the same（～5.2 GPa）. Therefore, Ti and N contents should be controlled properly when preparing Cu（Ti, N） films.