| 摘要 |
化學機械拋光是現在半導體產業中最常被使用的平坦化製程。拋光液中化學溶液的腐蝕與磨粒的機械磨削兩者雙重的作用，使得化學機械拋光能造成晶圓薄膜表面全面平坦化的效果。製程中使用的磨粒與拋光過程中產生的碎屑、副產物，會造成拋光墊表面孔洞產生鈍化的現象，降低繼續輸送拋光液的功能，進而影響晶圓材料的拋光移除率以及表面不均勻度。利用修整器來移除拋光墊表面的鈍化層，將使得拋光墊表面再生露出新的孔洞，繼續運送拋光液的功能。修整過程中由於拋光墊鈍化層及研磨液的作用，會使得修整器鑽石磨耗，造成修整率下降而影響晶圓拋光品質及效能，本研究將藉由修整器設計參數之改變，提升修整率之穩定度，同時延長修整器之使用壽命增加工業實用性。本研究探討工作鑽石數量對修整器壽命的影響，接著研究修整器的設計參數包括：鑽石晶形、間距及大小對工作鑽石多寡與修整器壽命的影響，並觀察隨著修整器使用時間的增加，拋光墊表面粗糙度之變化。實驗發現修整器上鑽石粒度較大、間距較小以及鑽石晶形較完整其磨耗速率較慢但工作鑽石量較少，而隨著修整器使用時間增加拋光墊表面粗糙度將顯著下降。
關鍵字：鑽石修整器、工作鑽石、修整率、表面粗糙度
Chemical mechanical polishing (CMP)
is the mostly used planarization process in the semiconductor
industry today. Due to the dual actions of chemicals corrosion
and abrasive abrasion in the slurry, CMP achieves the effect of
global planarization on the thin film surface of wafers. The
abrasive, debris and by-product generated in the process cause
the pores of the pad surface glazing, which in turn renders the
performance of transporting slurry to decrease. Accordingly, the
removal rate (RR) and non-uniformity (NU) will be affected. The
diamond dressers are used to remove the glazing layer of the pad
surface. This action makes the ability of pad in transporting
the slurry restored. The diamond dressers were worn by slurry
and the glazing layer of the pad surface caused dressing rate
decreased. The dresser lifetime was improved by changing the
parameters of dresser on this study. This study was made to
observe and discuss the wear mechanisms of the diamond dressers.
First, the diamond dressers with different number of working
diamonds were made and the effects of lifetime of dressers were
explored. Then, it was observed that the number of working
diamonds varies with different types of dressers. The dressing
simulation was made to examine the lifetime and the surface
condition of the ceramic dressers with different diamond shapes,
sizes and pitches. It was found from experimental data that the
diamonds with larger pitches、sharper shape and smaller size wore
faster, and the pad surface roughness decreased as dressing rate
decreased.
Keywords: Diamond Dresser,
Lifetime, Dressing Rate, Surface Roughness
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