Study on ultrasonic-assisted chemical mechanical polishing

Because of the continuous improvement of the wafer size and line width, the CMP process must be promoted and improved. Many studies have been undertaken to try and achieve both a high material removal rate (MRR) while still maintaining a high surface quality of silicon wafer. However, up until now, it appears that the two objectives are mutually exclusive. In this paper, an innovative method which integrated ultrasonic machining and CMP (UCMP) has been developed. The CMP efficiency and the quality of polished surface improved considerably. The basic principle effects of ultrasonic are further illustrated and the experiments had been done to demonstrate the proper procedure. The results showed that UCMP achieves a higher material removal rate (MRR) and better surface quality at the same time. Copyright © 2011 Inderscience Enterprises Ltd.