电子器件超声键合接合部形成特征及电性能研究
摘要
超声引线键合作为微电子封装中被广泛应用的技术,在工艺上已经很成熟,但是关于其键合机理和连接过程在学术界仍然没有达成共识,而且随着微电子器件的微小化和高效率化,又出现许多问题函待解决,所以对超声键合的研究有很重要的科研和生产参考价值。
本课题研究的目的在于通过具体的试验为超声键合机理理论研究提供必要数据,为实际生产提供优化参数。
本文通过实验测量了键合点的横向宽度和接合面电阻值,应用数据处理软件Minitab分析试验数据,并绘制相应的三维响应图,在研究各种超声输入参数对超声键合质量影响效果的同时,深入探讨了影响键合过程的隐含因素,本文的研究内容主要包括以下几个方面:
(1)试验设计,采用标准25μmAl+1%Si引线与三种(Au/Ni/Cu ,Cu和Ni/Cu)不同的金属化膜进行试验并取得试验数据,试验数据用Minitab软件拟合分析,研究了超声输入参数(主要参数为超声功率、键合压力、键合时间)对键合点的形状以及接合面电阻值的影响效果,并且对参数进行优化。
(2)研究了接合面形貌结构在输入参数变化情况下的演变趋势,为了证明其合理性,将键合点老化之后进行机械拉伸将引线去除,与化学方法进行对照,还以各种影响为对象研究了连接机理。
(3)设计超声键合点接合面电阻测试电路,分别以三种输入功率为变量分析单一输入参数对接合面电阻值的影响效果,根据电阻值的演变曲线研究接合电阻的隐含影响因素。
通过试验结果分析认为金属化膜的硬度对于键合过程存在一定影响;键合点的断裂模式从断裂位置上可以分为三种,并且与输入参数存在一定的关系。电阻的测试试验结果得出电阻值的影响因素存在着交互作用。
Ultrasonic bonding, as a technology of microelectronic pakaging,has been used widely, but the mechanism of bonding and process of the joining are controversial all the time. With the development of the electrocal device, there are many new problems. So the study of the ultrasonic bonding is significant.
The aim of the investigation is to optimize the ultrasonic processing parameters and supply the experiment data.
This paper investigated the width of joint and interficial resistance in experiment, analysed the data by Minitab and got 3D surface plot. The effects of process parameters on the bonding quality were studied. Simultaneously, those crytic influencing factors were also investigated. Totally speaking, the thesis includes the following parts:
(1) DOE(design of experiment), Al+1%Si wire with 25μm diameter and three kinds of pads (Au/Ni/Cu pad , Cu pad and Ni/Cu pad) were bonded and the data were got. The data were analysed and fitted. The effects of the parameters (ultrasonic power, bonding time and bonding force) on the formation of joint and interfacial resistance were studied. Processing parameters were also optimized.
(2) The tendency of the joining interface was studied with development of the parameters. To certify the rationality, the wire of joint aged was uncovered and compared to the chemical method to uncover the wire. The bonding mechanism was investigated for the factors.
(3) The test circuit of interficial resistance was designed. As the variable , The parameters was used to analyse the tendency of interficial resistance. The factors were investigated by the curve of resistance.
From the results of the experiment, it is indicated that the hardness of the pad plays an important role on the bonding. There are three kinds of models of failures, and they were relative to parameters. The factors of resistance take mutual action.
本课题研究的目的在于通过具体的试验为超声键合机理理论研究提供必要数据,为实际生产提供优化参数。
本文通过实验测量了键合点的横向宽度和接合面电阻值,应用数据处理软件Minitab分析试验数据,并绘制相应的三维响应图,在研究各种超声输入参数对超声键合质量影响效果的同时,深入探讨了影响键合过程的隐含因素,本文的研究内容主要包括以下几个方面:
(1)试验设计,采用标准25μmAl+1%Si引线与三种(Au/Ni/Cu ,Cu和Ni/Cu)不同的金属化膜进行试验并取得试验数据,试验数据用Minitab软件拟合分析,研究了超声输入参数(主要参数为超声功率、键合压力、键合时间)对键合点的形状以及接合面电阻值的影响效果,并且对参数进行优化。
(2)研究了接合面形貌结构在输入参数变化情况下的演变趋势,为了证明其合理性,将键合点老化之后进行机械拉伸将引线去除,与化学方法进行对照,还以各种影响为对象研究了连接机理。
(3)设计超声键合点接合面电阻测试电路,分别以三种输入功率为变量分析单一输入参数对接合面电阻值的影响效果,根据电阻值的演变曲线研究接合电阻的隐含影响因素。
通过试验结果分析认为金属化膜的硬度对于键合过程存在一定影响;键合点的断裂模式从断裂位置上可以分为三种,并且与输入参数存在一定的关系。电阻的测试试验结果得出电阻值的影响因素存在着交互作用。
Ultrasonic bonding, as a technology of microelectronic pakaging,has been used widely, but the mechanism of bonding and process of the joining are controversial all the time. With the development of the electrocal device, there are many new problems. So the study of the ultrasonic bonding is significant.
The aim of the investigation is to optimize the ultrasonic processing parameters and supply the experiment data.
This paper investigated the width of joint and interficial resistance in experiment, analysed the data by Minitab and got 3D surface plot. The effects of process parameters on the bonding quality were studied. Simultaneously, those crytic influencing factors were also investigated. Totally speaking, the thesis includes the following parts:
(1) DOE(design of experiment), Al+1%Si wire with 25μm diameter and three kinds of pads (Au/Ni/Cu pad , Cu pad and Ni/Cu pad) were bonded and the data were got. The data were analysed and fitted. The effects of the parameters (ultrasonic power, bonding time and bonding force) on the formation of joint and interfacial resistance were studied. Processing parameters were also optimized.
(2) The tendency of the joining interface was studied with development of the parameters. To certify the rationality, the wire of joint aged was uncovered and compared to the chemical method to uncover the wire. The bonding mechanism was investigated for the factors.
(3) The test circuit of interficial resistance was designed. As the variable , The parameters was used to analyse the tendency of interficial resistance. The factors were investigated by the curve of resistance.
From the results of the experiment, it is indicated that the hardness of the pad plays an important role on the bonding. There are three kinds of models of failures, and they were relative to parameters. The factors of resistance take mutual action.
引文
1 王毅. 高密度高性能电子封装技术的现状与发展.微电子技术.1998, 26(4): 1~22
2 Vslery M. Dubin. Electrochemical Aspects of New Materials and Technologies in Microelectronics. Microelectronic Engineering. 2003, 70(2):461~469
3 李枚. 微电子封装技术的发展与展望. 半导体杂志. 2000, 25(5):1~3
4 S. Murali, N. Srikanth, Charles J. Vath III. An Analysis of Intermetallics Formation of Gold and Copper Ball Bonding on Thermal Aging. Materials Rsearch Bulletin. 2003, 50(1):39~50
5 S. Murali, N. Srikanth, Charles J. Vath III. Grains, Deformation Substructures, and Slip Bands Observed in Thermosonic Copper Ball Bonding. Materials Characterization. 2003, 50(1):39~50
6 Hyoung-Joon Kim. Effects of Cu/Al Intermaetallic Compound (IMC) on Copper Wire and Aluminum Pad Bondability. Transaction on Components and Packaging Technologies. 2003, 26(2):367~374
7 Bruce L. Gehman. Bonding Wire Microelectronic Interconnections. IEEE Transactions on Components, Hybrids, and Manufacturing Technology. 1980, 3(3):375~383
8 吴懿平, 丁汉. 电子制造技术基础. 机械工业出版社, 2005:58~60
9 贾松良 . 微电子封装的发展及封装标准 . Information Technology & Application. 2003, (3): 35~37
10 方洪渊. 微电子器件铜丝球焊技术研究及其成球过程的数值模拟. 哈尔滨工业大学博士论文. 1990
11 S. Murali, N. Srikanth, Charles J. Vath III. Effect of Wire Size on The Formation of Intermetallics and Kirkendall Voids on Thermal Aging of Thermosonic Wire B onds. Materials Letters. 2004, 58(12):3096~ 3101
12 C. W. Tan. Corrosion Study at Cu-Al Interface in Microelectronics Packaging .A pplied Surface Science. 2002, 191(1-4):67~73
13 Kenji Toyozawa. Development of Copper Wire Bonding Application Technology.IEEE Transactions on Components, Packaging andManufacturing Technology. 1990, 13 (4):667~672
14 田春霞.电子封装用导电丝材料及发展.稀有金属. 2003, 6(27):782~787
15 J. N.Antonevich, R. E. Monroe. Fundamental Studies of Ultrasonic Welding. Welding Journal Research Supplement. 1960, (8):23~26
16 P. M. Uthe. Variables Affecting Weld Quality in Ultrasonic Aluminum Wire Bonding. Solid State Tech. 1969, (8):72~77
17 K. C. Joshi. The Formation of Ultrasonic Bonds Between Metals. Welding Journal. 1971, 6(50):840~848
18 F. A. Neppiras. Ultrasonic Welding of Metals. Ultrasonics. 1965, (3):128~135
19 R. D. Mindlin, W. P. Mason and T. J. Osmer.Effect of an Oscillating Tangential Force on the Contact Surfaces of Elastic Spheres. Pro. 1st National Congress on Applied Mechanics. 1952:203~208
20 K. L. Jonhson. Surface International Between Elastically Loaded Bodies Under Tandential Forces. Proc. Roy. Soc. 1955, (23):531~548
21 Vern H. Winchell, II, Howard M. Berg. Enhancing Ultrasonic Bond Development. IEEE Transactions on Components, Hybrids and Manufacturing Technology. 1978, 1(3):211~219
22 Or, Siu Wing. High Frequency Transducer for Ultrasonic Bonding. Hong Kong Polytechnic (People's Republic of China) PH.D Dissertation. 2001:1~19
23 G. Harman. Wire Bonding in Microelectronics, Materials, Processes, Reliability, and Yield. Second Edition. McGraw-Hill, 1997:21
24 George G. Harman and John Albers. The Ultrasonic Welding Mechanism as Applied to Aluminum-and Gold-Wire Bonding in Microelectronics. IEEE Transactions on Parts, Hybrids, and Packaging. 1977, 13(4):406~412
25 K. C. Joshi. The Formation of Ultrasonic Bonds Between Metals. Weld J(NY). 1971, 50(12):840~848
26 G. G. Harman and K. O. Leedy. An Experimental Model of the Microelectronic Wire Bonding Mechanism. The10th Annual Proc. Reliability Physics Symposium. Las Vegas, NE, 1972, (3):49~56
27 B. Langenecker. Effects on Ultrasound on Deformation Characteristics of Metals. IEEE Trans. on Sonics Ultrason. 1966, 13(1):1~8
28 A. Coucoulas. Ultrasonic Welding of Aluminum Leads to Tantalum Thin Films. Trans. on Met. Soc. AIME. 1966, (6):587~589
29 J. L. Chevalier, D. F. Gibbons, L. Leonard. High-Frequency Fatigue in Aluminum. J. Appl. Phys. 1972, 43(1):73~77
30 James E. Krzanowski. A Transmission Electron Microscopy Study of Ultrasonic Wire Bonding. IEEE Trans. on Components, Hybrids and Manufacturing Technology. 1990, 13(1):176~181
31 H. Kreye. Melting Phenomena in Solid-State Welding Process. Welding Journal (Miami, Fla). 1977, 56(5):154~158
32 C.D. Breach, F. Wulff. New Observations on Intermetallic Compound Formation in Gold Ball Bonds: General Growth Patterns and Identification of Two Forms of Au4Al. Microelectronics Reliability. 2004, 44(6):973~981
33 F. W. wulff, C. Breach and D. Stephan. Further Characterisation of Intermetallic Growth in Copper and Gold Ball Bonds on Aluminium Metallisation. 2005, (2):1~9
34 R. D. Mindlin. Compliance of Elastic Bodies in Contact. Journal of Applied Mechanics. 1949:259~268
35 K. C. Joshi. The Formation of Ultrasonic Bonds Between Metals. Welding Journal. 1971, 50(12):840~848
36 B. D. Martin. Design and Use of a Laser Interferometer for Ultrasonic Bonding Studies. 14th Annu.Proc. Reliability Physics Symp.1976, 12(3):82~85
37 谢敬华, 李小平, 范良志等. 提高引线键合机超声系统性能的若干因素的分析. 现代电子技术. 2003, 5(3):65~67
38 韩为民. 键合机中超声波的基本控制原理及方法. 电子工业专用设备. 2003, 8(5):21~26
39 张驰. MINITAB六西格玛解决方案. 广东经济出版社, 2003:387~390
40 计红军. 超声楔键合物理过程及其规律研究. 哈尔滨工业大学博士论文. 2005
41 李军辉, 韩雷, 谭建平等. Ni-Al超声楔键合分离界面的结构特性及演变规律. 焊接学报. 2004, 26(4):5~8
42 Yasuo Takahashi, Michinobu Inoue. Numerical Study of Wire Bonding-Analysis of Interfacial Deformation Between Wire and Pad. JournalElectronic Packaging. 2002, 3(6):27~36
43 G. G. Harman. Metallurgical Failure Modes of Wire Bonds. The 12th Annual Proc. Reliability Physics Symposium. Las Vegas, Nevada, 1974, 6(8):131~141
2 Vslery M. Dubin. Electrochemical Aspects of New Materials and Technologies in Microelectronics. Microelectronic Engineering. 2003, 70(2):461~469
3 李枚. 微电子封装技术的发展与展望. 半导体杂志. 2000, 25(5):1~3
4 S. Murali, N. Srikanth, Charles J. Vath III. An Analysis of Intermetallics Formation of Gold and Copper Ball Bonding on Thermal Aging. Materials Rsearch Bulletin. 2003, 50(1):39~50
5 S. Murali, N. Srikanth, Charles J. Vath III. Grains, Deformation Substructures, and Slip Bands Observed in Thermosonic Copper Ball Bonding. Materials Characterization. 2003, 50(1):39~50
6 Hyoung-Joon Kim. Effects of Cu/Al Intermaetallic Compound (IMC) on Copper Wire and Aluminum Pad Bondability. Transaction on Components and Packaging Technologies. 2003, 26(2):367~374
7 Bruce L. Gehman. Bonding Wire Microelectronic Interconnections. IEEE Transactions on Components, Hybrids, and Manufacturing Technology. 1980, 3(3):375~383
8 吴懿平, 丁汉. 电子制造技术基础. 机械工业出版社, 2005:58~60
9 贾松良 . 微电子封装的发展及封装标准 . Information Technology & Application. 2003, (3): 35~37
10 方洪渊. 微电子器件铜丝球焊技术研究及其成球过程的数值模拟. 哈尔滨工业大学博士论文. 1990
11 S. Murali, N. Srikanth, Charles J. Vath III. Effect of Wire Size on The Formation of Intermetallics and Kirkendall Voids on Thermal Aging of Thermosonic Wire B onds. Materials Letters. 2004, 58(12):3096~ 3101
12 C. W. Tan. Corrosion Study at Cu-Al Interface in Microelectronics Packaging .A pplied Surface Science. 2002, 191(1-4):67~73
13 Kenji Toyozawa. Development of Copper Wire Bonding Application Technology.IEEE Transactions on Components, Packaging andManufacturing Technology. 1990, 13 (4):667~672
14 田春霞.电子封装用导电丝材料及发展.稀有金属. 2003, 6(27):782~787
15 J. N.Antonevich, R. E. Monroe. Fundamental Studies of Ultrasonic Welding. Welding Journal Research Supplement. 1960, (8):23~26
16 P. M. Uthe. Variables Affecting Weld Quality in Ultrasonic Aluminum Wire Bonding. Solid State Tech. 1969, (8):72~77
17 K. C. Joshi. The Formation of Ultrasonic Bonds Between Metals. Welding Journal. 1971, 6(50):840~848
18 F. A. Neppiras. Ultrasonic Welding of Metals. Ultrasonics. 1965, (3):128~135
19 R. D. Mindlin, W. P. Mason and T. J. Osmer.Effect of an Oscillating Tangential Force on the Contact Surfaces of Elastic Spheres. Pro. 1st National Congress on Applied Mechanics. 1952:203~208
20 K. L. Jonhson. Surface International Between Elastically Loaded Bodies Under Tandential Forces. Proc. Roy. Soc. 1955, (23):531~548
21 Vern H. Winchell, II, Howard M. Berg. Enhancing Ultrasonic Bond Development. IEEE Transactions on Components, Hybrids and Manufacturing Technology. 1978, 1(3):211~219
22 Or, Siu Wing. High Frequency Transducer for Ultrasonic Bonding. Hong Kong Polytechnic (People's Republic of China) PH.D Dissertation. 2001:1~19
23 G. Harman. Wire Bonding in Microelectronics, Materials, Processes, Reliability, and Yield. Second Edition. McGraw-Hill, 1997:21
24 George G. Harman and John Albers. The Ultrasonic Welding Mechanism as Applied to Aluminum-and Gold-Wire Bonding in Microelectronics. IEEE Transactions on Parts, Hybrids, and Packaging. 1977, 13(4):406~412
25 K. C. Joshi. The Formation of Ultrasonic Bonds Between Metals. Weld J(NY). 1971, 50(12):840~848
26 G. G. Harman and K. O. Leedy. An Experimental Model of the Microelectronic Wire Bonding Mechanism. The10th Annual Proc. Reliability Physics Symposium. Las Vegas, NE, 1972, (3):49~56
27 B. Langenecker. Effects on Ultrasound on Deformation Characteristics of Metals. IEEE Trans. on Sonics Ultrason. 1966, 13(1):1~8
28 A. Coucoulas. Ultrasonic Welding of Aluminum Leads to Tantalum Thin Films. Trans. on Met. Soc. AIME. 1966, (6):587~589
29 J. L. Chevalier, D. F. Gibbons, L. Leonard. High-Frequency Fatigue in Aluminum. J. Appl. Phys. 1972, 43(1):73~77
30 James E. Krzanowski. A Transmission Electron Microscopy Study of Ultrasonic Wire Bonding. IEEE Trans. on Components, Hybrids and Manufacturing Technology. 1990, 13(1):176~181
31 H. Kreye. Melting Phenomena in Solid-State Welding Process. Welding Journal (Miami, Fla). 1977, 56(5):154~158
32 C.D. Breach, F. Wulff. New Observations on Intermetallic Compound Formation in Gold Ball Bonds: General Growth Patterns and Identification of Two Forms of Au4Al. Microelectronics Reliability. 2004, 44(6):973~981
33 F. W. wulff, C. Breach and D. Stephan. Further Characterisation of Intermetallic Growth in Copper and Gold Ball Bonds on Aluminium Metallisation. 2005, (2):1~9
34 R. D. Mindlin. Compliance of Elastic Bodies in Contact. Journal of Applied Mechanics. 1949:259~268
35 K. C. Joshi. The Formation of Ultrasonic Bonds Between Metals. Welding Journal. 1971, 50(12):840~848
36 B. D. Martin. Design and Use of a Laser Interferometer for Ultrasonic Bonding Studies. 14th Annu.Proc. Reliability Physics Symp.1976, 12(3):82~85
37 谢敬华, 李小平, 范良志等. 提高引线键合机超声系统性能的若干因素的分析. 现代电子技术. 2003, 5(3):65~67
38 韩为民. 键合机中超声波的基本控制原理及方法. 电子工业专用设备. 2003, 8(5):21~26
39 张驰. MINITAB六西格玛解决方案. 广东经济出版社, 2003:387~390
40 计红军. 超声楔键合物理过程及其规律研究. 哈尔滨工业大学博士论文. 2005
41 李军辉, 韩雷, 谭建平等. Ni-Al超声楔键合分离界面的结构特性及演变规律. 焊接学报. 2004, 26(4):5~8
42 Yasuo Takahashi, Michinobu Inoue. Numerical Study of Wire Bonding-Analysis of Interfacial Deformation Between Wire and Pad. JournalElectronic Packaging. 2002, 3(6):27~36
43 G. G. Harman. Metallurgical Failure Modes of Wire Bonds. The 12th Annual Proc. Reliability Physics Symposium. Las Vegas, Nevada, 1974, 6(8):131~141