Abstract
Chemical Mechanical Polishing is the most effective method in planarization of semiconductor industry. Because of the continuous improvement of the wafer size and line width, the technology of CMP process must be promoted and improved. We work hard to achieve high material removal rate and high surface quality all the time, but it seems too difficult to achieve both aims in reality. In this paper, we suggested an innovative method which integrated ultrasonic vibration assisted machining with CMP, and supposed it would promote the efficiency and quality of manufacturing via the character of ultrasonic vibration. This research illustrated the basic principle of ultrasonic vibration and the effects caused by ultrasonic vibration in the interface between wafer and pad, then, we proved the above hypothesis according to the results. However, the result indicated that the MRR and surface roughness had obvious improvement such as the average MRR increased 24.3% and the average Ra reduced from 0.0508μm to 0.0316μm by using ultrasonic vibration assisted CMP (UCMP). Besides, we also found the optimum parameters by DOE method which the pressure was 4psi, the rotational speed of platform was 25rpm, the rotational speed of carrier was 20rpm, and the amplitude was 14μm.