화학공학소재연구정보센터
Journal of Vacuum Science & Technology B, Vol.26, No.1, 141-150, 2008
Effect of temperature on copper damascene chemical mechanical polishing process
The effects of different process parameters on tribology and surface defects were studied till date, but there has been minimal study to understand the effect of temperature on the copper chemical mechanical polishing (CMP) process. The effect of temperature on tribology and surface defects during copper CMP employing different pad materials and slurries has been explored. From the results, it was seen that the coefficient of friction and removal rate increased with an increase in slurry temperature during polishing. The experimental data indicated that the increase in temperature results in an increase in amounts of metal dishing and metal loss. The dishing and metal loss in the interconnect features initially increased with an increase in temperature and then decreased at elevated temperatures. With an increase in temperature the copper films peeled off from the wafer due to low adhesion with low-k dielectric material at higher temperatures. The electrical properties of the planarized devices showed drastic degradation with increase in dishing values. Also the temperature showed a significant effect on pad physical and mechanical properties with an increase in temperature. The increase in temperature also increased the crystallinity of the copper film. (c) 2008 American Vacuum Society.