The Effect of Alkaline Slurry on Low-K Film
As the integrated circuits developing, the line-width and space between the metal interconnection are shrinking. This increases the RC time delay. To reduce the RC time delay, the low dielectric constant (low-k) material was introduced in the ICs. For process integration considerations, the impact of electronic characters was investigated. In this paper, both static test and CMP(chemical mechanical polishing) process conditions were executed on the low-k material black diamond (BD) with slurry,which was explored by Hebei University of Technology. The slurry was utilized to evaluate the effect on the dielectric properties of BD films. Electrical analyses have shown dielectric properties of BD films would not be degraded during these processes. The static test was dipping the low–k material (BD)in the slurry for 30s and 2minutes, and the results showed the capacitance changed from 3.01to3.40 when dipping in 30s ,and the value reached 3.71 when dipping 2minutes. The resistance changed from 2.9-2.95 to 3.27-3.33 in 30s,and reached 3.57-3.63 in 2 minutes. The result of CMP process showed that the capacitance of five dots , which were selected on the BD film, changed from 2.94-2.98to 2.99-3.05. The dielectric integrity of low k BD films after CMP process remained at an acceptable region to meet requires of multilevel interconnection.
Pengcheng Wang, Liqun Ai, Yungang Li, Xiaoming Sang and Jinglong Bu
Y. Hu et al., "The Effect of Alkaline Slurry on Low-K Film", Advanced Materials Research, Vols. 295-297, pp. 1621-1624, 2011