不同材質軟墊之微觀機械性質對軟墊研磨界面效應之影響

Effects of Micro-Mechanical Properties on Polishing Interfacial Phenomena of Polish Pad with Different Material

吳仲傑(ZHONG-JIE WU)

指導教授 ： 鄭友仁

國立中正大學/工學院/機械工程學系/碩士(2014年)

摘要

精密研磨製程通常需要使用研磨軟墊，研磨的技術自新石器時代即使用於青銅鏡及玉飾品的鏡面磨光，近年來更廣泛地應用於精密加工上，像是光學鏡片、滾珠螺桿，甚至半導體晶圓等材料表面的精密加工。而軟墊研磨中最具代表性的就是化學機械研磨，化學機械研磨是軟墊與工件呈相對運動並搭配研磨液，達到拋光研磨的效果，本研究主要探討不同材質軟墊機械性質的差異對軟墊研磨界面效應的影響，建立一套軟墊選用的準則。
在進行上，本研究選用發泡類及纖維類二類研磨軟墊，透過微觀動態機械分析方法(Nano Dynamic Mechanical Analysis, Nano-DMA)量測軟墊的機械性質，並用探針模擬實際研磨時軟墊的受力情況，進而測得軟墊在實際研磨情況下的機械性質，再將全新軟墊進行研磨，觀察軟墊經過研磨過後其機械性質的變化情況，探討不同材質軟墊的老化現象的差異。理論部分，本研究藉由力學接觸模型來推算材料粗糙峰移除的情況，將實驗所量測的機械性質套進理論模型，分析不同材質之全新軟墊機械性質與經過研磨後軟墊機械性質的變化，探討軟墊機械性質對材料移除情況的影響。
本研究結果發現發泡類軟墊其機械性質較軟，針對粗糙峰起伏大的工件時，能使工件有效達到平坦化效果，且壽命較長，本研究推斷軟墊的孔隙為影響壽命的可能原因，另外纖維類軟墊其機械性質較硬，針對粗糙峰起伏小且密集的工件時，能使工件達到拋光的效果，不過其壽命較短。
本研究將以往軟墊選用的經驗及由測試與邏輯現象的觀察，歸納成有理論根據的科學觀點，整理出一套研磨軟墊針對材料粗糙峰等級之選用規則，可做為業界在軟墊研磨製程開發設計的參考，並提供軟墊研磨製程相關參數調控及工具機設計開發之準則。

關鍵字

微觀機械性質 ； 研磨軟墊 ； 拋光

並列摘要

A soft pad has been used to polish high quality fine surfaces since ancient times. The drive for precision components and miniaturized devices in recent decade renders the use of soft pad polishing necessary for a wide array of applications including precision machine components, optical devices and semiconductor wafers. Chemical-mechanical polishing is widely used for polishing. Chemical-mechanical polishing is a relative motion with pad and work-piece. This can achieve the effect of polishing. This study mainly investigates the effects of differences in the mechanical properties of the material for the effect of the polishing interfacial phenomena which establishes a criteria selection of pad.

In this study, we chose PU pad and fiber pad, measure the mechanical properties by Nano Dynamic Mechanical Analysis, simulate the actual polishing pad’s forcing condition with the probe, and thus obtain the pad’s mechanical properties under the polishing condition. Later we need the new pad,for polishing observed the changes in the pad’s mechanical properties so that exploring the different decaling phenomena between different kinds of pads. In the theoretical part of the study, we calculate the condition of material removed by micro-contact model, set the mechanical properties measuring from experimental into the theoretical model, and then analyze the changes of mechanical properties between the new pad and the polishing pad to explore the effect of the pads’ mechanical properties with the removal condition.

The results of this study revealed that the mechanical properties of the PU pad is relatively soft, undulating larger roughness peaks against the work-piece which can effectively achieve the planarization and longer lifetime. Hence we concluded that the possible reason of affecting lifetime is the pad’s pores, and the fiber pad’s mechanical property is harder, undulating smaller and concentrated roughness peaks can enable the work-piece to achieve polished results, but its lifetime is shorter.

並列關鍵字

Polishing ； Micro-Scale Mechanical Property ； Soft Pad

參考文獻

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