超聲振動輔助化學機械拋光之研究

Study on Ultrasonic Vibration Assisted Chemical Mechanical Polishing

張耀晟(Yao-Cheng Chang)

指導教授 ： 左培倫

國立清華大學/工學院/動力機械工程學系/碩士(2010年)

https://doi.org/10.6843/NTHU.2010.00048

摘要

化學機械拋光是半導體製程中達到全域平坦化最有效之方法，隨著晶圓大尺寸及小線寬的發展趨勢，其相關技術有提升與改善之必要性。在製程上，高材料移除率與高拋光品質一直是我們追求的目標，但實際上卻不可兼得。因此本論文中提出一改善方法，將超聲振動輔助加工技術與化學機械拋光相整合，藉由超聲振動的特性，以期達到增進製程效能之目標。本文中介紹超聲振動產生的基本原理，並提出超聲振動在拋光界面所產生之效應及相關理論，透過實驗驗證上述理論。結果顯示：超聲輔助化學機械拋光對試片之材料移除率以及表面品質皆有顯著的改善；在一定參數設定下，最適合之實驗參數：拋光壓力為4psi、平台轉速為25rpm、載具轉速為20rpm、振動振幅為14μm。其平均材料移除率可以提高24.3％，而其平均表面粗糙度由0.0508μm下降為0.0316μm。

關鍵字

化學機械拋光 ； 平坦化 ； 超聲振動輔助加工 ； 材料移除率 ； 表面粗糙度

並列摘要

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.

並列關鍵字

Chemical Mechanical Polishing ； Planarization ； Ultrasonic Vibration Assisted Machining ； Material Removal Rate ； Surface Roughness

參考文獻

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