CMP(Chemical-Mechanical Planarization)為化學機械平坦化製程被應用於IC製造。在半導體線寬縮減的迫切需求下，穩定性和可用性於CMP製程已成為非常重要的課題。然而目前國內外尚未有線上量測裝置來監控與判定拋光墊性能狀態，使得拋光墊無法被有效率的修整，導致耗材費用居高不下。本研究自行研發設計線上監控量測系統與拋光墊性能水準 (Performance Level, PL)分析再修整性與再使用性，於製程中搭配拋光盤旋轉與搖臂移動，以彩色共軛焦(Chromatic Confocal)技術擷取含水膜拋光墊的表面形貌資訊進行量化指標分析與判定。系統採用靜態量測比對線上監控結果，比對結果顯示Spk具有82.7 %之高度相關性。將系統應用於監控馬拉松式矽晶片拋光之拋光墊配合晶圓品質監控，研究顯示拋光墊均勻度(Pad Uniformity, PU)走向趨勢若陡升25.89 %或Sa小於8.92 μm或Spk小於8.21 %或碎形維度(Fractal Dimension, FD)小於1.39必須再修整否則晶圓會產生刮傷與拋光效率降低；當有效壽命指標(Pad Effective Lifetime Index, PELI)下降至0.47以及碎形維度小於1.43，拋光效率下降55.70 %，拋光墊已無法再使用需立即更換。基於分析PU、Sa、Spk、FD與PELI，可作為使用者判斷拋光墊再修整與再使用性，進而達到拋光墊使用率最大化並減少更換次數之目的。

Chemical-mechanical planarization (CMP) has been known as a process for global and local planarization in IC fabrication. Due to urgent demand of conducting wires downsizing to nanometer, the stability and availability of CMP process have become critically significant. Currently, the CMP process for on-line measurement device to monitor the surface topography of pad in diamond dressing is not available, thus the polishing pad cannot be so efficiently dressed and evaluated in production. This study aims to develop an on-line monitoring measurement system to analyze the performance level of polishing pad. In this study a chromatic confocal sensor is attended on a designed fixture an arm to acquire pad topography data. The pad topography of total working area is detected by rotation of polishing pad and arm motion. The dynamic measurement of the on-line system has been compared with that of static measurement. Results show that Spk of pad is 82.7 %, which means high correlation. Normally, in CMP process the surface of the pad is covered with deionized water(DIW). The system can be used to monitor the pad performance during polishing of the silicon wafer. Results show that once the trend of the pad uniformity (PU) increases to 25.89 %, Sa value of the pad is less than 8.92 μm, Spk value is less than 8.21 % or fractal dimension (FD) value is less than 1.39, then the pad needs to be dressed. Otherwise, scratches may appear on the silicon wafer surface after CMP. Moreover, once the pad effective lifetime index (PELI) drops to 0.47 or FD is less than 1.43, based on experimental set-up, the polishing efficiency of silicon wafer decreases to 55.70 % and the pad is evaluated on functionless and needs to be replaced. From experimental results, the value of PU, Sa, Spk, FD and PELI can be considered as performance level index for re-dressing and reusability of the pad. Further the on-line monitoring measurement system could be applied on pad optimization in CMP process.

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