由軟墊之微觀機械性質探討 軟墊研磨再修整製程之平坦化能力

On the Planarization Capability of Soft Pad Dressing Process：From the Characterization of Micro-Scale Mechanical Property of Soft Pad

涂煥城(Hvan-Cheng Tu)

指導教授 ： 鄭友仁

國立中正大學/工學院/機械工程學系/碩士(2012年)

摘要

軟墊研磨製程會搭配鑽石修整器（Diamond Disk Dresser）對軟墊表面進行修整，以恢復軟墊研磨製程的效益，是此精密研磨製程的關鍵。以往有關再修整製程的探討，大多專注於由巨觀角度研究操作參數或修整器對製程的影響。針對軟墊研磨再修整製程，本研究提出一微觀動態分析技術（Micro Scale Dynamic Mechanical Analysis Technique），來模擬研磨界面間不同高度的粗糙峰滑過軟墊時對軟墊造成的受力情形，並測得再修整製程前後研磨軟墊表面的回饋效應，接著結合理論分析，深入探討鑽石修整器設計影響軟墊平坦化結果的主要設計條件。
本研究利以建立微觀動態分析方法，檢測軟墊表面機械性質，發現在不同研磨及再修整階段，其表面機械性質有明顯的差異。測試結果發現到軟墊表面機械性質隨研磨製程進行而衰退，並在再修整製程進行後回復的現象。本研究更進一步發現不同設計鑽石修整器，對研磨軟墊表面機械性質有不同的回復能力。接著結合再整修製程中軟墊的實驗量測結果以及軟墊、工件及研磨顆粒三者間接觸界面的力學模型，建立了軟墊研磨平坦化理論模式。成功地連結再修整製程變因與軟墊研磨製程結果的關係，來探討鑽石修整器不同設計對研磨軟墊平坦化能力之影響，接著利用數據分析估算鑽石修整器使軟墊性質回復比例，並以之探究鑽石修整器設計影響軟墊平坦化結果的主要設計條件。分析結果顯示鑽石幾何形狀為研磨軟墊機械性質與軟墊研磨製程平坦化能力回復的重要關鍵。
本研究建立了軟墊再修整製程的系統化分析方法，以檢測軟墊性能的回復能力。並針對不同設計鑽石修整器對軟墊表面性能變化的影響進行探討。本研究結果極具前瞻學術探討與精密加工及鑽石修整器的產業應用潛力，為精密表面加工製程和製造系統的關鍵技術。

關鍵字

研磨軟墊 ； 修整 ； 微觀機械性質 ； 拋光

並列摘要

That the polishing pad plays an important role in the soft pad polishing process. Due to mechanical loads and chemical reactions acting at the pad surface, the pad surface will be glazed and worn. Consequently, the physical properties of a polishing pad are expected to change during polishing and the performance will decay. To overcome these effects and to recover the pad performance, a diamond disk dresser is passed over the soft pad with an applied down force. Without this pad conditioning process, removal rate drops off dramatically over a short time. However improper of dressing parameters or dresser design can create excess wear on the soft pad thickness and groove and then lose polishing capability.
Previous studies on the performance of soft pad polishing process with the texture and groove change for the soft pad surface after pad dressing process mainly based on the macroscopic observation. However, the major material behavior during polishing process that lead to planarization and soft pad performance change are occurring at the contact interface of pad and workpiece surface asperities. Consequently, the bulk measurement and observation results are not sufficient to provide the insight of planarization performance decay and aging effect of soft pad during polishing process.
This pioneering research provides a micro scale dynamic mechanical analysis method that probes the micro mechanical behavior of a soft pad surface under contact with different asperity heights. The results reveal that the polishing pad exhibit a stimulus adaptive local viscoelasticity under the activation of asperity contact.The viscoelastic properties and surface structure of pads with different conditioning parameters have been characterized using this process.
Furthermore, a micro-contact model is developed to describe the contact behavior among a pad, a work piece and a particle. Subsequently, this study establishes a material removal rate model that accounts for the micro contact behavior, amount of the polishing particle, and penetration depth of the particle. The model of material removal rate is used to calculate the material removal of different surface heights for pads with different dresser design based on the mechanical property characterized. The calculating results identify the planarization performance of soft pads after different conditioning process. Finally, the effects of diamond dresser design factors on the change of pad surface properties were investigated.
The results of current study provide a experimental and theoretical foundation for the selection and fabrication of a diamond disk dresser. Furthermore, the current research provide the guidelines for the design of the machine tool and the selection of operation parameters during conditioning process that cannot be achieved with empirical findings and phonological approaches.

並列關鍵字

Soft Pad ； Dressing ； Micro-Scale Mechanical Property ； Polishing

參考文獻

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