【摘要】：化學機械拋光作為一種具有獨特優(yōu)勢的加工工藝手段,在微電子領域以及光學加工領域已經有著十分廣泛的應用�；瘜W機械拋光中,拋光液作為提供化學反應物質,排除加工碎屑的加工介質,在工藝中占有重要地位。拋光液的流動過程能夠將拋光所需的化學物質以及磨料輸送至拋光墊表面、帶走摩擦生成的熱量以及加工產物,維持穩(wěn)定的拋光加工環(huán)境,同時,拋光液在流動中能夠在工件與拋光墊之間建立具有承載力的潤滑薄膜,改善工件與拋光墊的接觸狀態(tài)。為了能夠弄清化學機械拋光加工中拋光液流動規(guī)律,研究拋光墊表面形貌對拋光液流動的影響,優(yōu)化拋光墊表面形貌來控制拋光液的流動,本文開展了以下研究:1.平整的無溝槽拋光墊表面拋光液流動狀態(tài)分析。使用流體力學方程推導拋光液在無粘性假設下的流動狀態(tài),使用有限元法對拋光液流動行為進行的仿真結果顯示,拋光液由于由內而外的加速運動趨勢以及增大的濕周長度,液面高度呈現(xiàn)明顯下降,流動均勻性差。使用粒子圖像測速實驗驗證了仿真結果。2.結合多相流模型的有限元仿真和粒子圖像測速實驗,探索了具有溝槽的拋光墊表面拋光液的流動特性。拋光液在拋光墊溝槽中流動,受到明顯的阻擋作用,拋光液流動的沿程能量損失顯著,相比于平整無溝槽拋光墊表面的情況,具有溝槽的拋光墊表面流動具有更高的液膜厚度,不易導致碎屑的沉降,有利于高效排出碎屑;拋光液從內而外的徑向流動速度變動也得到了一定程度的改善。對多種不同溝槽網格形狀的拋光墊中流動狀態(tài)進行了比較和討論,結果顯示網格形狀為正六邊形時,拋光液流動的均勻性最佳。3.拋光墊表面溝槽優(yōu)化設計。在對拋光液流動沿程能量損失的理論下,對拋光墊表面溝槽進行了優(yōu)化設計,優(yōu)化涉及溝槽寬深比、溝槽尺寸以及溝槽沿拋光墊表面的分布走向。使用有限元仿真手段對優(yōu)化的溝槽中拋光液流動狀態(tài)進行了分析,結果顯示其流動徑向速度均勻,且具有一致的液面高度,實驗結果也顯示溝槽中徑向流速均勻一致,達到了預期的優(yōu)化效果。
[Abstract]:Chemical mechanical polishing (CMA) has been widely used in the field of microelectronics and optical processing as a kind of processing technology with unique advantages. Polishing fluid plays an important role in the process of chemical mechanical polishing. The flow process of the polishing liquid can transport the chemicals and abrasives needed for polishing to the surface of the polishing pad, take away the heat generated by friction and the processing products, and maintain a stable polishing environment, at the same time, The lubricating film with bearing capacity can be established between the workpiece and the polishing pad during the flow of the polishing liquid, and the contact state between the workpiece and the polishing pad can be improved. In order to make clear the flow rule of polishing fluid in chemical mechanical polishing process, to study the effect of polishing pad surface morphology on polishing liquid flow, and to optimize the surface morphology of polishing pad to control the flow of polishing liquid, the following researches have been carried out in this paper: 1. Surface polishing fluid flow analysis of smooth grooveless polishing pad. The fluid dynamics equation is used to deduce the flow state of the polishing fluid under the assumption of non-viscosity. The simulation results of the flow behavior of the polishing liquid by using the finite element method show that the polishing fluid is due to the tendency of acceleration from inside to outside and the increase of the wet cycle length. The height of liquid level decreased obviously and the flow uniformity was poor. The experimental results of particle image velocimetry are used to verify the simulation results. 2. Based on the finite element simulation of multiphase flow model and particle image velocimetry experiment, the flow characteristics of polishing fluid on the surface of polishing pad with grooves are investigated. The flow of polishing fluid in the grooves of the polishing pad is obviously blocked, and the energy loss along the course of the flow of the polishing fluid is significant. Compared with the case of leveling the surface of the polishing pad without grooves, the surface flow of the polishing pad with grooves has a higher liquid film thickness. It is not easy to cause detritus sedimentation, which is beneficial to the removal of detritus efficiently. The variation of radial velocity of polishing fluid from inside to out has also been improved to some extent. The flow state of polishing pad with different groove mesh shapes is compared and discussed. The results show that the uniform flow of polishing fluid is the best when the mesh shape is hexagonal. 3. Surface groove optimization design of polishing pad. Based on the theory of energy loss along the polishing fluid flow, the groove on the surface of the polishing pad is optimized, which involves the ratio of width to depth, the size of the groove and the distribution of the groove along the surface of the polishing pad. The flow state of polished liquid in the optimized grooves is analyzed by finite element simulation. The results show that the radial velocity is uniform and the liquid level is uniform. The experimental results also show that the radial velocity in the grooves is uniform and consistent. The desired optimization effect is achieved.
【學位授予單位】：南京航空航天大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TG175

【參考文獻】

相關期刊論文 前10條

1 武鵬;周建偉;何彥剛;劉玉嶺;秦然;張燕;;磨料粒徑對多層Cu布線CMP的影響[J];微納電子技術;2015年11期

2 鐘靜;魏昕;謝小柱;楊向東;;CMP過程中拋光墊表面溝槽對液膜厚度影響研究[J];制造技術與機床;2015年05期

3 王金普;白林山;儲向峰;;不同磨料對微晶玻璃化學機械拋光的影響[J];納米技術與精密工程;2015年01期

4 趙曉兵;李志娜;錢程;陳楊;;殼層形態(tài)對核/殼結構PS/SiO_2復合磨料拋光性能的影響[J];摩擦學學報;2014年05期

5 王陳;李慶忠;朱N，

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