在超大型積體電路(Ultra-large-scale Integrated, ULSI)中化學機械研磨(Chemical Mechanical Polishing, CMP)是目前唯一能提供晶圓金屬層和介電層全面平坦化(Global Planarization)之技術，然而，傳統化學機械研磨機台包含許多缺點(如研磨終點之不確定性、化學研磨液浪費導致污染問題、研磨時間長與成本高等諸多問題)。本研究主要設計一仰面式化學機械研磨系統(Face-up Chemical Mechanical Polishing System)與提出控制策略，藉由光學測量迴授並對此系統進行閉迴路即時控制。
仰面式化學機械研磨系統主要由晶圓載台(Wafer Carrying Platform)、研磨墊載台(Pad Carrying Platform)、磁控加壓模組(Magnetic Drive Pressurized Module)與控制器(Controller)所構成。晶圓載台透過撓性聯軸器與感應馬達連接進行傳動，透過所搭配的變頻器使感應馬達產生定速轉動使得CMP正常運作。雷射位移感測器即時量測出工件表面粗糙度後透過電腦運算，藉由2D高精密位移平台(High-precision Linear-motor Stage)驅動上方的移動加壓塊到預研磨位置，並透過磁控加壓模組對系統產生環狀施壓，克服傳統上晶圓的內環面與外環面加工不一致的情形發生，達到快速平坦化，故可以使得每片工件處理的時間降低，不僅大幅節省成本也可提高產能。
首先，本論文利用接觸力學、能量法、電磁學理論推導CMP以及磁控加壓模組之系統動態，並對其進行電腦模擬分析。就控制觀點而言，仰面式化學機械研磨系統為一開迴路不穩定且非線性的系統，故本研究以回授線性化(Feedback Linearization)的方法設計一參考模型適應控制器(Model Reference Adaptive Controller)來進行閉迴路控制，使其能夠穩定而又能準確算出材料移除率(Material Removal Rate, MRR)。
最後，本研究成功地製作了一個仰面式化學機械研磨控制系統之雛形，搭配訊號處理模組(即資料擷取卡NI 9215)及介面軟體(LabVIEW)進行實驗驗證。由實驗結果得知，本論文所設計之仰面式化學機械研磨能夠將工件的粗糙度降低約88%，加上閉迴路控制後更能使研磨狀況大幅改善，大致上克服了傳統化學機械研磨機台的諸多缺點。

Chemical Mechanical Polishing (CMP) has been playing the key role to achieve near-perfect planarity of interconnection and metal layers for Ultra-Large-Scale Integrated (ULSI) devices. An innovative design for face-up chemical mechanical polishing control system by feedback of optical measurements is proposed by this thesis. The online optical measurement and real-time feedback are integrated to eliminate the shortcomings of traditional approaches. e.g., the batch-to-batch discrepancy of required polishing time, and non-uniformity across the wafer. In addition, the discrepancy of terminal points to polish and undesired contamination caused by chemical slurry can be both effectively reduced.
The face-up CMP system mainly consists of a wafer carrying platform, a pad carrying platform, a magnetic drive pressurized module and adaptive controller. The wafer carrying platform is driven by an induction motor through a flexible coupling so that the wafer can be touched and grinded by the polishing pad. The surface roughness of wafer is on-line measured and fed to the controller by three laser displacement sensor sets. Meanwhile, the magnetic drive pressurized module is moved to the local region whose surface height is the largest by a high-precision linear-motor stage, following the commands of controller. That is, the local region material removal rate can be controlled via feedback of the measurements by the laser displacement sensors. One of the major advantages of the proposed method is that the finish of surface roughness can be consistent, no matter where the inner-ring area or outer-ring area is concerned. Furthermore, it is able to overcome the Edge Effect (traditionally, the interfacial induced stress near the wafer edge is much higher than that near the wafer center).
The micro-contact mechanics theory, energy method and fundamental electromagnetic principles are applied to derive the dynamics of face-up CMP system. From the viewpoint of stability, the CMP system is an unstable in open-loop sense. In addition, its mathematical model is nonlinear. Hence, a Model Reference Adaptive Controller (MRAC) is synthesized to comply with the feedback linearization model.
Finally, a prototype of face-up CMP system is successfully built up in this research. By employing the signal processing interface (Data Acquisition Board: NI 9215) and the commercial simulation software (LabVIEW), the feasibility of the proposed design is verified by computer simulations and intensive experiments. The surface roughness can be reduced by under MRAC. To sum up, by using the proposed face-up CMP system, the cost of the entire machining cycle can be much reduced while the quality of the finished goods is upgraded.

[1] 前田和夫(鄭正忠譯), “半導體製造裝置”, 普林斯頓國際有限公司, 台北, 22-39, 2003.
[2] 土肥俊郎(王建榮等人編譯), “半導體平坦化CMP技術,” 全華科技圖書股份有限公司, 台北, 1-1~1-10, 2000.
[3] F. B. Kaufman, S. A. Cohen and M. A. Jaso, “Characterization of defects produced in TEOS thin films due to chemical-mechanical polishing (CMP),” J. Electrochem. Soc., 138, 3460, 1991.
[4] F. Preston, “Optimization of Computer Controlled Polishing,” Glass Tech, Vol. 11, pp. 214-219, 1927.
[5] J. Tichy, J. A. Levert, L. Shan and S. Danyluk, “Contact Mechanics and Lubrication Hydrodynamics of Chemical Mechanical Polishing,” J. Electrochem. Soc., Vol.146, pp.1523-1528, 1999.
[6] N. Saka, T. Eusner and J. H. Chun, “Nano-Scale Scratching in Chemical-Mechanical Polishing,” CIRP Annals - Manufacturing Technology, 57, pp. 341-344, 2008.
[7] 許厲生, “矽晶圓薄化與平坦化加工研究,” 博士論文, 國立台灣科技大學, 台北, 2007.
[8] M. Bhushan, R. Rouse and J. E. Lukens, “Chemical-Mechanical Polishing in Semi-direct Contact Mode,” J. Electrochem. Soc., Vol.142, pp.3845-3851, 1995.
[9] J. F. Archard “Contact and Rubbing of Flag Surfaces,” Journal of Applied Physics, Vol. 24, pp.981-985, 1953.
[10] L. M. Cook, “Chemical Process in Glass Polishing,” Journal of Non-Crystalline Solid, Vol. 120, 152, 1990.
[11] W. T. Tseng and Y. L. Wang, “Re-examination of Pressure and Speed Dependences of Removal Rate during Chemical Mechanical Polishing Process,” J. Electrochem. Soc., Vol. 144, No. 2, 1997.
[12] S. R. Runnels and L. M. Eyman, “Tribology Analysis of Chemical Mechanical Polishing,” J. Electrochem. Soc., Vol. 141, No. 6, pp. 1698-1700, 1994.
[13] F. G. Shi and B. Zhao, “Modeling of Chemical Mechanical Polishing with Soft Pad,” Applied Physics A: Material Science and Processing, Vol. 67, pp. 249-252, 1998.
[14] B. Zhao and F. G. Shi, “Chemical Mechanical Polishing: Threshold Pressure and Mechanism,” Electrochemical and Solid-State Letters, Vol. 2, pp. 145-147, 1999.
[15] C. Liu, B. T. Dai, W. T. Tseng and C. F. Yeh, “Modeling of Wear Mechanism during Chemical-Mechanical Polishing,” Journal of Electrochemical Society. 143, 2, 716, 1996.
[16] D. Wang, A. Zutshi, T. Bibby, S. P. Beaudoin and T. S. Cale , “Effects of carrier film physical properties on CMP,” Thin Solid Films, 345, pp. 278-283, 1999.
[17] P. Ara and M. Erin, “Slurry Utilization Efficiency Studies in Chemical Mechanical Planarization,” Japanese Journal of Applied Physics, 42. pp. 7259-7264, 2003.
[18] T. S. Yang, Y. C. Wang, K. S. Chen, Y. J. Chen and J. L. Yan, “Optimization of Wafer-Back Pressure Profile in Chemical Mechanical Planarization,” J. Electrochem. Soc., 155(10), pp. 720-729, 2008.
[19] J. A. Greenwood and J. B. P. Williamson, “Contact of Nominally Flat Surface,” Proc. Roy. Soc. London, A295, pp. 300-319, 1966.
[20] 林雲海, “電磁學,” 銀禾文化事業公司, 1985.
[21] J. G. Kim, K. S. Park, N. C. Park, H. Yang and Y. P. Park, “Improved Air Gap Control Using Optimized Antishock Control Algorithm for SIL-based Near-field Storage System,” International Symposium on Optomechatronic Technologies, pp. 98-103, 2009.
[22] K. L. Johnson, “Contact mechanics,” Cambridge University Press, Cambridge, pp. 406-416, 1989.
[23] 王柏村, “振動學,” 全華科技圖書股份有限公司, 2003.
[24] M. Y. Tsai, S. T. Chen, Y. S. Liao and J. Sung, “Novel Diamond Conditioner Dressing Characteristics of CMP Polishing Pad.” International Journal of Machine Tools and Manufacture, Vol.49, pp. 722-729, 2009.
[25] J. H. Wu, M. L. Lee and T. S. Lai, “The Dynamic Analysis of a Flat Plate Under a Moving Load by The Finite Element Method,” International Journal for Numerical Methods in Engineering, Vol. 24, pp. 743-762, 1987.
[26] G. T. Michaltsos, “Dynamic Behavior of a Single-Span Beam Subjected to Loads Moving with Variable Speeds,” Journal of Sound and Vibration, Vol.258, pp. 359-372, 2002.
[27] J. M. Gere and B. J. Goodno, “Mechanics of Materials,” 7th version (SI Edition), Cengage Learning, 2011.

[28] H. P. Lee, “Dynamic Response of a Beam with Intermediate Point Constraints Subject to a Moving Load,” Journal of Sound and Vibration, Vol.171, pp. 361-368, 1994.
[29] 楊憲東, “非線性控制,” Sept. 2011.
[30] 廖德祿, “適應控制,” Sept. 2012.
[31] P. V. Osburn, H. P. Whitaker and A. Kezer, “New Developments in The Design of Model Reference Adaptive Control Systems.” ISA 29th Annual Meeting, paper 61-39. New York, 1961.
[32] P. C. Gregory, “Self Adaptive Flight Control Symposium.” Wright-Patterson Air Force Base, 1959.
[33] D. E. Seborg, T. F. Edgar and S. L. Shan, “Adaptive Control Strategies for Process Control: A Survey.” AIChE Journal 32, pp. 881-913, 1986.
[34] 南榮電機，http://www.banlancingmachine.com/
[35] H. D. Currence and W. G. Lovely, “ANALYSIS OF SOIL SURFACE ROUGHNESS,” Transactions of the American Society of Agricultural Engineers, Vol. 13, pp. 710-714, 1970.
[36] R. Saxena, “Feature Scale Modeling AND Experiments for
Chemical Mechanical Planarization,” Rensselaer Polytechnic
Institute Troy, 2002.