在超大型積體電路中，化學機械研磨扮演著使晶圓金屬層和介電層平坦化的重要角色。高穩定性與高效能的化學機械研磨製程需要將研磨液持續均勻的注入晶圓與研磨墊之交界面，因此在研磨墊上通常必需刻製溝槽以利研磨液之流動，並且幫助研磨液將晶圓磨除後的雜質順利排出，防止雜質堆積刮傷晶圓表面。本文從潤滑理論和接觸力學模型出發，建立含有溝槽研磨墊接觸應力和流場計算之二維理論模型，以探討研磨液流場流動特性。我們並進行廣泛之參數研究，以找出最佳化之製程參數設定。
結果發現晶圓背部壓力提高使得交界面接觸應力上升，進而使流體壓力與材料移除率增加，且材料移除率之不均勻度在特定參數範圍中有一最小值。同時，當接觸比逐漸降低亦即晶圓與研磨墊之接觸面積減少時，其交界面接觸應力也將上升，進而讓流體壓力增加；然而，晶圓與研磨墊之接觸面積減少，雖然局部材料移除率提高，但全面材料移除率則會降低。另外，我們從材料移除率之不均勻度最小值，能夠找出晶圓背部壓力的最佳參數值。

Chemical mechanical planarization (CMP) has played an enabling role in producing near-perfect planarity of interconnection and metal layers in ultralarge-scale integrated (ULSI) devices. For stable and high performance of CMP, it is important to ensure uniform slurry flow at the pad-wafer interface, hence necessitating the use of grooved pads that help discharge debris and prevent subsequent particle loading effects. Here, on the basis of two- dimensional lubrication theory and contact mechanics models, we calculate CMP slurry flow with a grooved pad. Through extensive parameter studies, we examine the effects of pad groove designs on the slurry flow characteristics, and attempt to find the optimal process parameter settings.
Our results indicate that increasing the wafer back pressure would increase the contact stress on the pad-wafer interface, so that the fluid pressure and material removal rate (MRR) are increased as well. It is also found that the wafer back pressure may be tuned to reduce the MRR non-uniformity to a minimum within a prescribed process parameter range. Moreover, as the presence of pad grooves reduces the contact area between the pad and wafer, the contact stress and fluid pressure on the pad-wafer interface therefore also are increased, resulting in increased local MRR. However, the overall MRR is decreased due to reduced total contact area.

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