非等向性電鍍銅於積體電路內連線之研究｜國立清華大學博碩士論文庫

簡易檢索 / 詳目顯示

回結果列表

研究生：	吳邦豪 Bang-Hao Wu
論文名稱：	非等向性電鍍銅於積體電路內連線之研究 Analysis of Anisotropic Copper Electroplating for IC Interconnects
指導教授：	萬其超 Chi-Chao Wan 王詠雲 Yung-Yun Wang
口試委員:
學位類別：	博士 Doctor
系所名稱：	工學院 - 化學工程學系 Department of Chemical Engineering
論文出版年：	2003
畢業學年度：	91
語文別：	英文
論文頁數：	147
中文關鍵詞：	電鍍銅、電化學分析、銅內連線、無孔電鍍、有機添加劑、模擬、吸附、電流密度分佈
外文關鍵詞：	Copper Electroplating, Electrochemical analysis, Copper Interconnects, Void-free deposition, Organic additive, Simulation, Adsorption, Current density distribution
相關次數：	點閱：3 下載：0
分享至:	分享至facebook 分享至twitter

查詢本校圖書館目錄查詢臺灣博碩士論文知識加值系統勘誤回報

本論文主要是利用電化學法來分析電鍍銅於積體電路內連線的研究。文中除了採用電化學模擬來分析不同電鍍尺度下的電流密度分佈外（第二章），也於第三章中利用電化學分析有機添加劑（聚乙二醇）在銅電極表面上的吸附行為，進而得到一種利用單一添加劑便可以無孔沉積（void-free）的機制。第四章則是結合以前其他學者所做的模擬分析結果，推導出數學模型用來說明何以單劑型無孔沉積會發生在某些特定的濃度下（聚乙二醇的濃度為10-6M）。
由第二章所做的多離子電鍍模型分析結果可以發現，在晶圓尺度（wafer scale）下的電鍍平整性主要是受到電鍍槽本身的歐姆阻力和電鍍銅反應的動力學阻力所控制。隨著硫酸濃度的增加，歐姆阻力逐漸降低使得電鍍銅的平整性也愈好。但因為動力學阻力也會隨硫酸濃度增加而增加，因此當硫酸超過某一含量後，平整性的改善也愈趨飽和。故吾人提出在實際操作上，應該將硫酸濃度對鍍層平整性的影響分成濃度傾向（concentration-preferred）和動力學傾向（kinetic-preferred）兩個範圍。至於在特徵尺度（feature scale）的毫微米小孔沉積方面，理論分析結果提出鍍層的填孔能力主要是受到反應通量跟擴散通量的比值所控制。當硫酸銅的濃度愈高，擴散通量的增幅大於反應通量的增幅，因此得到較好的填孔效果。同樣地，有關銅濃度對於填孔力的影響也可以分為濃度傾向和動力學傾向兩種控制方法。另外，吾人也將模擬結果放大到12吋晶圓的電鍍情形觀察填孔能力對晶圓上不同位置的毫微米孔洞有何不同。發現在晶圓邊緣的小孔將因為局部反應通量較大的關係，而不利於填孔行為。

第三章則利用循環伏安（Cyclic voltammetry）、線性掃描伏安法（Linear sweep voltammetry）、定電流法（Chronopotentiometry）和交流阻抗頻譜（Impedance）來量測聚乙二醇在銅電極上的吸附行為。添加劑的表面覆蓋率可以利用定電流法或交流阻抗計算電雙層的電容來求得。發現其吸附等溫線可以用Toth等溫線作描述，並且其吸附自由能為-51.67kJ mol-1，代表聚乙二醇具有很強的吸附能力於銅金屬表面上。因為在低添加劑濃度下，其吸附速率也會較慢，因此發現電流的磁滯現象（hysteresis）也能在單一添加劑情況下發生。藉由添加劑的吸附研究，吾人得到單一添加劑的無孔電鍍確實可行。此超充填的機制吾人稱之為不均勻的添加劑吸附分佈。

第四章中則是提出一個考量流場對添加劑的吸附作用之理論模式。藉由量測不同吸附平衡常數對雷諾數（Reynolds number）的變化，吾人可以求得理論模式中所需的實驗參數。模擬結果發現的確在恰好接近飽和表面覆蓋率所對應的添加劑濃度(10-6M PEG）有相對較大的小孔底部電流。模擬結果的確能預測於第三章的實驗所觀察的現象。

Void-free electroplating for IC copper interconnects was examined theoretically and experimentally. In Chapter 2, a theoretical model based on electrochemistry and thermodynamic calculation for species’ microscopic concentrations was developed to discuss the effect of base electrolyte concentration on the wafer-scale deposition uniformity and the feature-scale filling ability. The results show that the competitive effects of kinetic resistance to ohmic resistance and the reaction flux to the diffusion flux govern the deposition uniformity and the filling ability, respectively. Inverse contribution of CuSO4 and H2SO4 for deposition uniformity or filling ability was found. Process operation could be divided into two regions, concentration-preferred and kinetic-preferred. The model was also extended to simulate a 12-inch wafer to show the uniformity of the filling ability. Simulation results were compared to experiments and good agreement was found.
According to the adsorption study of PEG on copper electrode at 1ASD (1 A dm-2), a void-free deposition by single additive is achievable. The idea of developing a single additive system was raised from the characteristics of current-potential response of acid copper sulfate bath with PEG, Cl- and their combination. Surface coverage of adsorbent could be obtained by either chronopotentiometry (calculated by the equation derived in this study) or EIS (calculated by Frumkin’s parallel plate model). Adsorption isotherm was fitted to Toth isotherm and good agreement was found. Large negative value of the standard free energy for PEG adsorption implies the strong adsorption of PEG on copper surface. Results derived by CV and adsorption study suggested a new filling mechanism called “uneven adsorption mechanism” induces the super-filling. The shortcomings of the previous two filling mechanisms were also discussed in Chapter 3.

In Chapter 4, a theoretical model was proposed to involve the effect of hydrodynamics on the adsorption kinetics of PEG. Some assumptions were applied to estimate the fluid flow condition inside the submicron trench. In combination with adsorption kinetic parameters experimentally determined, the model provides a theoretical support for the occurrence of uneven adsorption in moderate PEG concentration.

Abstract I
中文摘要 III

List of Figures V

List of Tables IX

Chapter 1. Introduction and Literature review 1

1-1. Introduction 1

1-2. Literature review 3

1-2-1. Electroplating of copper into submicron features 3

1-2-2. Fundamental electrode kinetics 12

1-2-3. Scale analysis and current distribution 15

1-2-4. Modeling of copper electroplating for IC via/trench filling 19

1-2-5. Fundamental adsorption isotherms of additives 26

1-2-6. Effect of additives on electroplating of copper 28

1-2-7. Surface coverage measurement- by electrochemical method 35

1-3. Motivation and objective of this research 40

References 42

Chapter 2. The Effect of Base Electrolyte Composition on the Microscopic Filling Ability and Macroscopic Deposition Uniformity of Copper Electroplating 47

2-1. Introductions 47

2-2. Theory 50

2-2-1. Thermodynamic calculation of speciation in electrolyte 50

2-2-2. Numerical solver for microscopic concentration 54

2-2-3. Electrode kinetics 55

2-2-4. Potential theory in wafer scale simulation 57

2-2-5. Calculation of species’ surface concentration 59

2-2-6. Numerical solver for computing current density 63

2-3. Results and Discussions 64

2-3-1. Microscopic concentration 64

2-3-2. Deposition modeling 69

2-3-3. Comparison of Simulations and Experiments 83

2-4. Conclusions 86

Appendix: Simplified feature scale model 87

List of symbols 90

References 92

Chapter 3. Void-free anisotropic deposition for IC interconnect with poly(ethylene glycol) as the single additive based on uneven adsorption distribution 94

3-1. Introduction 94

3-2. Experiments 96

3-3. Results and Discussions 99

3-4. Conclusions 119

List of symbols 120

References 121

Chapter 4. Simulation of feature scale copper electroplating based on uneven poly(ethylene glycol) adsorption 123

4-1. Introduction 123

4-2. Modeling and Experiments 125

4-2-1 Modeling formulation 125

4-2-2 Experimental 130

4-3. Results and discussions 132

4-4. Conclusions 141

List of symbols 142

References 143

Chapter 5. Conclusions 145

1. H. S. Rathore and D. Nguyen, “Effect of scaling of interconnection”, Copper metallization for sub-micron integrated, 8, 1998.
2. S. P. Heng et. al., International Symposium on VLSI TSA, 164, 1995.
3. 陳來助, “ULSI 超大型積體電路之銅導線技術”, 電子與材料, 1, 85, 1998.
4. D. Edelstein, J. Heidenreich, R. Goldblatt, W. Cote, C. Uzoh, N. Lustig, P. Roper, T. McDevitt, W. Motsiff, A. Simon, J. Dukovic, R. Wachnik, H. Rathore, R. Schulz, L. Su, S. Luce and J. Slattery, Technical Digest, IEEE International Electron Devices Meeting, 773, 1997.
5. R. J. Contolini, L. Tarte, R. T. Graff and L. B. Evans, VMIC Conference, 27-29, 1995.
6. P. C. Andricacos, C. Uzoh, J. O. Dukovic, J. Horkans, H. Deligianni, IBM J. Res. Develop. 42, 567-573, 1998.
7. G. Holmbom and B. E. Jacobsson, Surface and Coatings Technology, 35, 333-341, 1988.
8. T. Kobayashi, J. Kawasaki, K. Mihara and H. Honma, Electrochemica Acta, 47, 85-89, 2001.
9. W. C. Gau, T. C. Chang, J. Vac. Sci. Technol. A, 18, 656-660, 2000.
10. R. D. Mikkola, Q. T. Jiang and B. Carpenter, Plating & Surface Finishing, 81-85, 2000.
11. J. J. Kelly, C. Tian and A. C. West, J. Electrochem. Soc., 146, 2540-2545, 1999.
12. C.Madore, D.Landolt, J. Electrochem. Soc., 143, 3936-3942, 1996.
13. D. Stoychev, Trans IMF, 76, 73-80, 1998.
14. J. J. Kelly and A. C. West, J. Electrochem. Soc., 145, 3472-3476, 1998.
15. P. Taephaisitphongse, Y. Cao and A. C. West, J. Electrochem. Soc., 148, C492-C497, 2001.
16. T. P. Moffat, J. E. Bonevich, W. H. Huber, A. Stanishevsky, D. R. Kelly, G. R. Stafford and D. Josell, J. Electrochem. Soc., 147, 4524-4535, 2000.
17. J. Newman, Eletrochemical System, Second Edition, 1991.
18. A. J. Bard, L. R. Faulkner, Electrochemical methods, John Wiley & Sons, Inc., Second Edition, 2001., and references therein.
19. R. Cabán., T. W. Chapman, J. Electrochem. Soc., 124, (9), 1371, 1977.
20. J. O. Dukovic, IBM J. Res. Develop. 37, 125-141, 1993.
21. Y. Cao, P. Taephaisitphongse and A. C. West, J. Electrochem. Soc., 148, C466-C472, 2001.
22. C. Wagner, J. Electrochem. Soc., 98, 116-128, 1951.
23. T. Kessler and R. Alkire, Plating and Surface Finishing, 63, 22-27, 1976a.
24. T. Kessler and R. Alkire, Plating and Surface Finishing, 123, 990-999, 1976b.
25. J. L. Blue, The Bell System Technical Journal, 59(2), 169-182, 1980.
26. M. Matlosz, C. Creton, C. Clerc and D. Landolt, J. Electrochem. Soc., 134, 3015-3021, 1987.
27. A. C. West and J. Newman, J. Electrochem. Soc., 138, 1620-1625, 1991.
28. R. Bialecki, R. Nahlik, and M. Lapkowski, Electrochimica Acta, 29, 905-910, 1984.
29. J. Deconinck and G. Maggetto, J. Electrochem. Soc., 132, 2960-2965, 1985.
30. H. Shin and H. W. Pickering, J. Electrochem. Soc., 134, 551-558, 1987.
31. W. R. Parrish and J. Newman, J. Electrochem. Soc., 116, 169-172, 1967.
32. W. R. Parrish and J. Newman, J. Electrochem. Soc., 117, 43-48, 1970.
33. R. Alkire and A. A. Mirarefi, J. Electrochem. Soc., 120, 1507-1515, 1973.
34. D. A. Hazlebeck and J. B. Talbot, AIChE Journal, 36, (8), 1145, 1990.
35. J. O. Dukovic and C. W. Tobias, J. Electrochem. Soc., 137, (12), 3748-3755, 1990.
36. A. C. West, C. C. Cheng and B. C. Baker, J. Electrochem. Soc., 145, 3070-3074, 1998.
37. A. C. West, J. Electrochem. Soc., 147, 227-232, 2000.
38. A. C. West, S. Mayer and J. Reid, Electrochemcal & Solid-State Letters, 4, C50-C53, 2001.
39. D. Varadarajan, C. Y. Lee, A. Krishnamoorthy, D. J. Duquette and W. N. Gill, J. Electrochem. Soc., 147, 3382-3392, 2000.
40. K. M. Takahashi and M. E. Gross, J. Electrochem. Soc., 146, 4499-4503, 1999.
41. S. S. Kruglikov, N. T. Kudryavtsev and U. I. Sinyakov, Trans. Inst. Met. Finish., 44, 152, 1966.
42. D. Roha and U. Landau, J. Electrochem. Soc., 137, 824, 1990.
43. K. G. Jordan and C. W. Tobias, J. Electrochem. Soc., 138, 1251, 1991.
44. C. C. Cheng and A. C. West, J. Electrochem. Soc., 144, 3050, 1997.
45. C. C. Cheng and A. C. West, J. Electrochem. Soc., 145, 560, 1998.
46. C.Madore, M.Matlosz, D.Landolt, J. Electrochem. Soc., 143, 3927-3935, 1996.
47. I. Langmuir, J. Am. Chem. Soc., 40, 1361, 1918.
48. A. C. West, S. Mayer and J. Reid, Electrochemical &. Solid-State Letter, 4, C50-C53, 2001.
49. A. N. Frumkin, Z. Phys. Chem., 116, 166, 1925.
50. M. Paunovic and M. Schlesinger, Fundamentals of Electrochemical Deposition, John Wiley & Sons, Inc., 1998, and references therein.
51. G. Hope and G. Brown, Proc. Electrochem. Soc., 96-8, 215, 1996.
52. M. R. Hill and G. T. Rogers, J. Electroanal. Chem., 86, 179, 1978.
53. D. Stoychev and C. Tsvetanov, J. Appl. Electrochem., 26, 741, 1996.
54. M. Yokoi, S. Konishi and T. Hayashi, Denki Kagaku oyobi Kogyo Butsuri Kagaku, 52, 218, 1984.
55. Z. Nagy, J. P. Blaudeau, N. C. Hung, L. A. Curtiss and D. J. Zurawski, J. Electrochem. Soc., 142, L87-L89, 1995.
56. T. C. Franklin, Plating & Surface Finishing, 81, 62-67, 1994.
57. 萬其超, 電化學之原理與應用, 徐氏基金會出版, 初版十刷, 民國85年.
58. M. W. Breiter and S. Gilman, J. Electrochem. Soc., 109, 622, 1962.
59. M. W. Breiter, Electrochim. Acta., 8, 447, 1963.
60. M. Paunovic and R. Oechslin, Plating, 58, 599, 1971.
61. T. Mimani and S. M. Mayanna, J. Electrochem. Soc., 140, 984-988, 1993.
62. P. Kern and D. Landolt, J. Electrochem. Soc., 148, B228-B235, 2001.
63. T. Kessler and R. Alkire, Plat. Surf. Finish., 63, 22-27, 1980.
1. A. C. West, C. C. Cheng, Brett C. Baker, J.Eelectrochem.Soc., 145, 3070, 1998.
2. A. C. West, J.Eelectrochem.Soc., 147, 227, 2000.
3. J. O. Dukovic, IBM J. Res. Develop., 37, 125, 1993.
4. D. Varadarajan, C. Y. Lee, A. Krishnamoorthy, D. J. Dquette, W. N. Gill, J.Eelectrochem.Soc., 147, 3382, 2000.
5. John Newman, Electrochemical System, Second Edition, 1991.
6. D. A. Hazlebeck, J. B. Talbot, AIChE Journal, 36, (8), 1145, 1990.
7. S. Wasylkiewicz, J. Piotrowicz, Comput. Chem. Engng., 12, 141, 1988.
8. S. Wasylkiewicz, Fluid Phase Equilibria, 57, 277, 1990.
9. J. M. Casas, F. Alvarez, L. Cifuentes, Chemical Engineering Science, 55, 6223, 2000.
10. K. S. Pitzer, Thermodynamics (3rd Edition), McGraw-Hill, 1995.
11. K. S. Pitzer, J. Chem. Soc. Faraday Trans II, 68, 101, 1972.
12. K. S. Pitzer, R. N. Roy, L. F. Silvester, Journal of the American Chemical Society, 99, 4930, 1977.
13. C. C. Chen, H. I. Britt, J. F. Boston, L. B. Evans, AIChE Jl, 25, 820, 1979.
14. C. F. Baes, Jr., E. J. Reardon, B. A. Moyer, J. Phys. Chem., 97, 12343, 1993.
15. P. G. M. Brown, J. E. Prue, Proc. Roy. Soc., A, 232, 320, 1955.
16. D. C. Price, W. G. Davenport, Metallurgical Transitions B, 11B, 159, 1980.
17. R. Cabán., T. W. Chapman, J. Electrochem. Soc., 124, (9), 1371, 1977.
18. R. Y. Ying, Z. Mao, R. E. White, J.Eelectrochem.Soc.,135, 2964, 1988.
19. Y. Awakura, T. Doi, Metallurgical Transaction B, 19B, 5, 1988.
20. C. Wagner, J.Eelectrochem.Soc.,98, 116, 1951.
21. K. M. Takahashi, M. E. Gross, J.Eelectrochem.Soc., 146, 4499, 1999.
22. P. C. Andricacos, C. Uzoh, J. O. Dukovic, J. Horkans, H. Deligianni, IBM J. Res. Develop, 42, 567, 1998.
23. E. K. Yung, T. L. Romankiw and R. C. Alkire, J.Eelectrochem.Soc., 136, 206, 1989.
24. T. Kessler and R. Alkire, J.Eelectrochem.Soc., 123, 990, 1976.
25. G. K. K. Poon and D. J. Williams, J. Electron. Manuf., 15, 1998.
1. P. Taephaisitphongse, Y. Cao and A. C. West, J. Electrochem. Soc., 148, C492, 2001.
2. T. P. Moffat, J. E. Bonevich, W. H. Huber, A. Stanishevsky, D. R. Kelly, G. R. Stafford and D. Josell, J. Electrochem. Soc., 147, 4524, 2000.
3. J. J. Kelly and A. C. West, J. Electrochem. Soc., 145, 3472, 1998.
4. J. J. Kelly and A. C. West, J. Electrochem. Soc., 145, 3477, 1998.
5. D. Stoychev, Trans IMF, 76(2), 73, 1998.
6. J. D. Reid and A. P. David, Plating and Surface Finishing, 74, 66, 1987.
7. T. P. Moffat, D. Wheeler, W. H. Huber and D. Josell, Electrochemical & Solid-State Letters, 4(4), C26, 2001.
8. Y. Cao, P. Taephaisitphongse and A. C. West, J. Electrochem. Soc., 148, C466, 2001.
9. K. R. Hebert, J. Electrochem. Soc., 148, C726, 2001.
10. A. C. West, S. Mayer and J. Reid, Electrochemcal & Solid-State Letters, 4, C50, 2001.
11. W. C. Gau, T. C. Chang, J. Vac. Sci. Technol. A, 18, 656, 2000.
12. M. Hayase, M. Taketani, K. Aizawa, T. Hatsuzawa and K. Hayabusa, Electrochemical & Solid-State Letters, 5(10), C98, 2002.
13. T. C. Franklin, Plating & Surface Finishing, 81, 62, 1994.
14. A. J. Bard, L. R. Faulkner, Electrochemical methods, John Wiley & Sons, Inc., Second Edition, 2001., and references therein.
15. Z. Nagy, J. P. Blaudeau, N. C. Hung, L. A. Curtiss and D. J. Zurawski, J. Electrochem. Soc., 142, L87, 1995.
16. D. Stoychev and C. Tsvetanov, J. Appl. Electrochem., 26, 741, 1996.
17. K. G. Jordan and C. W. Tobias, J. Electrochem. Soc., 138, 1251, 1991.
18. C.Madore, D.Landolt, J. Electrochem. Soc., 143, 3936, 1996.
19. R. Cabán., T. W. Chapman, J. Electrochem. Soc., 124, 1371, 1977.
20. R. I. Masel, Principles of Adsorption and Reaction on Solid Surfaces, John Wiley & Sons, Inc., 1996, and references therein.
21. E. Gileadi, Electrode Kinetics, VCH Publishers, Inc. 1993, and references therein.
22. P. Kern and D. Landolt, J. Electrochem. Soc., 148, B228, 2001.
23. J. Toth, Acta Chim. Acad. Sci. Hung, 69, 311, 1971.
24. T. Mimani and S. M. Mayanna, J. Electrochem. Soc., 140, 984, 1993.
25. B. H. Wu, C. C. Wan and Y. Y. Wang, J. Electrochem. Soc., 150, C7, 2003.
26. A. C. West, C. C. Cheng and B. C. Baker, J. Electrochem. Soc., 145, 3070, 1998.
27. E. Lust, A. Janes, K. Lust, V. Sammelselg and P. Miidla, Electrochim. Acta, 42, 2861, 1997.
28. G. Jarzabek and Z. Borkowska, Electrochim. Acta, 42, 2915, 1997.
1. A. C. West, C. C. Cheng, Brett C. Baker, J.Eelectrochem.Soc., 145, 3070, 1998.
2. T. J. Pricer, M. J. Kushner and R. C. Alkire, J.Eelectrochem.Soc., 149, C406, 2002.
3. T. P. Moffat, D. Wheeler, W. H. Huber and D. Josell, Electrochemical & Solid-State Letters, 4(4), C26, 2001.
4. D. Varadarajan, C. Y. Lee, A. Krishnamoorthy, D. J. Dquette, W. N. Gill, J.Eelectrochem.Soc., 147, 3382, 2000.
5. T. P. Moffat, D. Wheeler, W. H. Huber and D. Josell, Electrochemical & Solid-State Letters, 5(4), C49, 2002.
6. M. Georgiadou and D. Veyret, J.Eelectrochem.Soc., 149, C324, 2002.
7. R. Chalupa, Y. Cao and A. C. West, J. Appl. Electrochem., 32, 135, 2002.
8. Y. Cao, P. Taephaisitphongse and A. C. West, J. Electrochem. Soc., 148, C466, 2001.
9. A. C. West, S. Mayer and J. Reid, Electrochemical & Solid-State Letters, 4 (7), C50, 2001.
10. B. H. Wu, C. C. Wan and Y. Y. Wang, J. Appl. Electrochem., accepted for publication.
11. K. R. Hebert, J. Electrochem. Soc., 148, C726, 2001.
12. J. O. Dukovic and C. W. Tobias, J. Electrochem. Soc., 137, (12), 3748-3755, 1990.
13. P. C. Andricacos, C. Uzoh, J. O. Dukovic, J. Horkans, H. Deligianni, IBM J. Res. Develop. 42, 567-573, 1998.
14. V. N. Kislenko, AD. A. Berlin and M. A. Moldovanov, Journal of Colloid and Interface Science, 173, 128-134, 1995.
15. K. M. Takahashi and M. E. Gross, J. Electrochem. Soc., 146, 4499-4503, 1999.
16. E. Gileadi, Electrode Kinetics for Chemists, Chemical Engineers, and Materials Scientists, VCH Publishers, New York, 1993., and references therein.

全文公開日期本全文未授權公開 (校內網路)
全文公開日期本全文未授權公開 (校外網路)
全文公開日期本全文未授權公開 (國家圖書館：臺灣博碩士論文系統)

簡易檢索 / 詳目顯示

相關論文