As a critical link of efficient and high-quality semiconductor substrate chemical mechanical polishing process, this paper focuses on the effects of the changes of the atmosphere to be processed on the CMP property of Si substrate. The experiment results showed that O2 existing in the processing atmosphere played an active role in facilitating material removal, and when the partial pressure of O2 in the processing atmosphere increased to 500kPa, the Si MRR of CMP reached 905nm/min. The Si material surface dissolutions in different atmospheres were analyzed respectively using SEM, EDS and light interference microscope. It was found that when O2 was sufficient, an extremely thin and tight oxide film was formed on the Si substrate surface, which prevented the furtherance of oxidation reaction, and compared with the Si-Si bonds, the Si-O bonds generated during this process were more inclined to undergo hydrolysis reaction; on the other hand, the O2 atmosphere caused the polishing pad, polishing particles and Si substrate to contact closely, increasing the mechanical friction and thus significantly improving the MRR. Based on the results of experiment and analysis, the Mechanisms of Si substrate polishing in high-pressure O2 atmosphere were summarized and a material removal model was built.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials