化學機械平坦化(Chemical Mechanical Planarization, CMP)已成為積體電路製程之關鍵技術，其中拋光墊(Polishing Pad)在整個CMP製程中扮演相當重要的角色，拋光墊的更換頻率影響到整個製程時間及穩定性。本研究進行CMP製程中，IC1000拋光墊之磨合期(Break-in Time)評估，以承壓面積比(Bearing Area Ratio, BAR)之反應區(Reaction Section)較大值與磨合期指標(Break-in Time Index, BTI)較小值，兩項指標分析拋光墊磨合時間與效果；由不同的修整參數對拋光墊進行修整，得知使用1.12psi及70rpm轉速可得到均勻表面粗糙度及較小移除量，並使用此參數進行磨合期測試，由實驗結果得知，拋光墊在修整12 min時，可得到承壓比最大反應區值為10.34%且磨合期指標為5.79；最後，利用銅膜晶圓進行CMP測試，並量測拋光墊承壓比反應區變化，當承壓比反應區維持在7.24%以上時，可得穩定銅膜晶圓平均移除率150.39 nm/min；在拋光過程中，銅膜晶圓表面粗糙度Sa最高值與最低值相差0.56nm，Sq值則相差0.65nm，未來可將磨合期指標應用至線寬20nm以下之銅化學機械平坦化製程。

Chemical Mechanical Planarization (CMP) has become a critical technology in current integrated circuits planarization process. Polishing pad plays an important role in the CMP process and the pad replacement frequency also affects the entire process throughput and stability. In this study, the break-in time of IC1000 pad has been investigated and a Break-in Time Index (BTI) has been developed based on the bearing area ratio (BAR) method of pad working layer for CMP process of copper blanket wafers. Experimental results of different parameters in pad dressing tests, the optimal parameter of 1.12psi and 70rpm can be determined to evaluate the break-in time of pad. As dressing 12 minutes, results show that the maximum reaction section is around 10.34% and break-in time index is obtained as 5.79. Then, 18 copper blanket wafers have been used to run CMP experiments and measurements of have been implemented to obtain the variation of pad reaction section. Results show that stable materials removal rate (MRR) of CMP copper blanket wafer is obtained as 150.39nm/min when the pad reaction maintains above 7.24%. The variation of surface roughness Sa and Sq of wafer after CMP can achieve only 0.56 nm and 0.65 nm respectively. Future study can focus on development of BTI for Cu-CMP process under 20 nm devices.

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