A new approach using plasma self-alignment after chemical mechanical polishing in a Cu damascene process has been developed. The Cu and a low k dielectric surfaces were treated by a novel plasma treatment in which hydrogen plasma, silane soak, and ammonia plasma treatment were used sequentially. The Cu and low k surface roughness, characterized by atomic force microscope, increased after plasma treatment. The surface bonds of Cu after treatment were characterized by x-ray photoelectron spectroscopy. Si-N bonds were formed on the Cu surface after the new plasma treatment. The interface of copper and silicon oxycarbide with new plasma treatment sequences had the highest deobonding fracture energy at 9.6 J/ cm2, which was measured by using the four-point bending test. The voltage breakdown of different plasma treatment conditions was evaluated by a single Cu damascene comb test structure capped with silicon oxycarbide. The new treatment had over 10 V improvement compared with others.
|Number of pages||6|
|Journal||Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures|
|Publication status||Published - 2008 Feb 8|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering