在化學機械研磨製程中機械性質之探討與分析

Abstract

化學機械拋光(Chemical-Mechanical Polishing)已是極大型積體電路(ULSI)製程 中被接受的一種晶圓表面平坦化技術。達到晶圓表面高移除率的同時，維持低的拋光非 均勻性(NU)一直是化學機械拋光製程追求的目標。在化學機械拋光製程中，速度和壓力 是決定移除率和拋光非均勻性的主要機械參數。在此研究中，模擬了150mm晶圓在研磨 頭和拋光墊不同轉速影響下相對速度的分佈和受材質特性影響下壓力的分佈，探討了移 除率的非均勻性與速度和壓力之間的關係，並與過去的Preston equation做比較。並建 立了一個新的理論模型且經由實驗證明其正確性。

Chemical-Mechanical Polishing (CMP) is a widely accepted manufacturing technology for topographical planarization during ultra-large scale integrated circuits (ULSI) process. Achieving high removal rates while maintaining a lowest possible polish nonuniformity (NU) across the wafer is most desirable goal during CMP process for practical applications. Velocity and pressure are the two most influential parameters in determining the removal rate and polish NU during CMP process. In this investigation, we examine the distribution of relative velocity of platen speed and carrier speed, and the applied pressure on 150 mm wafers by first-principles calculations and simulation. The dependence of removal rate and nonuniformity on velocity and pressure is studied and the results are compared with the classical Preston equation. A new theoretical analysis model on CMP is established and its validity is verified by experiments.