1、金线键合封装技术简介,ASM service: Jiang Haitao,2019/2/19,ASM Pacific Technology Ltd. 2009,page 2,Contents,Basic IntroductionUnderstand an IC Package IC Manufacturing FlowWire Bonding Introduction Gold Wire Bonder焊线封装工艺及分类WIRE BOND的基本原理及工艺图示焊线机的工艺机理及基本构架Bonding SequenceMaterial & ToolLead FrameCapillaryGold Wi
2、reWindow Clamp & Top Plate Bond Quality,2019/2/19,ASM Pacific Technology Ltd. 2009,page 3,Cross-section of an IC Package,2019/2/19,ASM Pacific Technology Ltd. 2009,page 4,IC Manufacturing Flow,2019/2/19,ASM Pacific Technology Ltd. 2009,page 5,Gold Wire Bonding,2019/2/19,ASM Pacific Technology Ltd. 2
3、009,page 6,焊线封装工艺,焊线封装工艺:用导线将半导体芯片上的电极与外部引脚相连接的工艺,即完成芯片与封装外引脚间的电流通路。,BGA,QFP,2019/2/19,ASM Pacific Technology Ltd. 2009,page 7,焊线封装工艺,QFN,Smart Card,2019/2/19,ASM Pacific Technology Ltd. 2009,page 8,焊线工艺分类,1。热超声/金丝球焊(Thermo-sonic bonding): 该工艺利用加热温度和超声能量使被压紧在一起的两种金属界面间形成焊接键合。目前90%以上的半导体封装技术采用该工艺Bond
4、ing Temperature is between 120Deg C to 240 Deg C. 2。超声楔焊(Ultrasonic): 利用超声能量作用于压紧在一起的两种金属间形成键合 Bonding Temperature=室温 3。热压焊(Thermo-compress bonding): 利用加热及压紧力形成键合。该技术 1957年在贝尔实验室被使用,是最早的 封装工艺技术,但现在已很少在用。Bonding Temperature 300 C.,2019/2/19,ASM Pacific Technology Ltd. 2009,page 9,热超声焊与超声楔焊比较,2019/2/1
5、9,ASM Pacific Technology Ltd. 2009,page 10,Bonding Parameters,What are the important parameters in Gold Wire Bonding?Thermo-sonic Bonding Bond Power ( Ultrasonic Power, Watt) Bond Force ( Gram force) Bond Time (ms) Bonding Temperature (C),2019/2/19,ASM Pacific Technology Ltd. 2009,page 11,Bonding Pr
6、inciple,2019/2/19,ASM Pacific Technology Ltd. 2009,page 12,WIRE BOND 的基本原理,2019/2/19,ASM Pacific Technology Ltd. 2009,page 13,WIRE BOND 的基本原理,2019/2/19,ASM Pacific Technology Ltd. 2009,page 14,金丝球焊工艺图示,2019/2/19,ASM Pacific Technology Ltd. 2009,page 15,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Lt
7、d. 2009,page 16,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 17,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 18,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 19,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 20,金丝球焊工艺图示(续),2019/2/19,ASM Pacifi
8、c Technology Ltd. 2009,page 21,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 22,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 23,金丝球焊工艺图示(续),2019/2/19,ASM Pacific Technology Ltd. 2009,page 24,热超声焊工艺机理,定义:用导线将半导体芯片上的电极与 外部引脚相连接的工艺,即完成芯片与 封装外引脚间的电流通路,在焊线制程中,在高温,超声波功率,压力及其 他
9、因素的作用下,象金和铝这样相互接触的两种 金属发生软化变形,同时两种金属间发生原子扩 散形成金属化合物(Intermatellic Compound) 或合金(Alloy),保证焊线 键合是可靠的电路连接。,2019/2/19,ASM Pacific Technology Ltd. 2009,page 25,热超声焊工艺机理,2019/2/19,ASM Pacific Technology Ltd. 2009,page 26,热超声焊工艺机理,2019/2/19,ASM Pacific Technology Ltd. 2009,page 27,热超声焊工艺机理,2019/2/19,ASM Pa
10、cific Technology Ltd. 2009,page 28,热超声焊工艺机理,2019/2/19,ASM Pacific Technology Ltd. 2009,page 29,自动焊线机之主要组成,2019/2/19,ASM Pacific Technology Ltd. 2009,page 30,热超声焊线机基本构架,2019/2/19,ASM Pacific Technology Ltd. 2009,page 31,热超声焊线机基本构架,2019/2/19,ASM Pacific Technology Ltd. 2009,page 32,Bonding Sequence,20
11、19/2/19,ASM Pacific Technology Ltd. 2009,page 33,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 34,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 35,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 36,Bonding Sequence,2019/2/19,ASM Pacific Technolo
12、gy Ltd. 2009,page 37,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 38,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 39,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 40,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 41,Bonding
13、 Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 42,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 43,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 44,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 45,Bonding Sequence,2019/2/19,ASM Paci
14、fic Technology Ltd. 2009,page 46,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 47,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 48,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 49,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,pag
15、e 50,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 51,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 52,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 53,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 54,Bonding Sequence,2019/2
16、/19,ASM Pacific Technology Ltd. 2009,page 55,Bonding Sequence,2019/2/19,ASM Pacific Technology Ltd. 2009,page 56,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 57,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 58,Material & Tools,2019/2/19,ASM Pacific Technology L
17、td. 2009,page 59,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 60,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 61,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 62,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 63,Material &
18、Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 64,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 65,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 66,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 67,Material & Tools,2019/2/19,ASM Pacific
19、Technology Ltd. 2009,page 68,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 69,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 70,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 71,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 72
20、,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 73,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 74,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 75,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 76,Material & Tools,金线 Gold Wi
21、re Manufacturer (MKE, MEM, Nippon, SUMITOMO, TANAKA. ) Gold Wire Data (Wire Diameter , Type , EL , TS)金线是键合工艺中非常重要的直接原材料,需要 符合以下要求: 正确的合金组份以保证合格的机械及电性能 适当的生产工艺与热处理 正确的尺寸(线径及长度) 合格的表面质量(表面清洁无污染或损伤) 良好的放线性能(可顺利的从线轴放线,无打弯或扭曲)金线来料检验 - 金线的主要测试指标是抗张强度(拉断力)及延展率 - 外观检验标准为表面完整性比较好的测试方法是使用 - 放线性能,2019/2/19,AS
22、M Pacific Technology Ltd. 2009,page 77,Material & Tools,2019/2/19,ASM Pacific Technology Ltd. 2009,page 78,Basic quality Measurement,2019/2/19,ASM Pacific Technology Ltd. 2009,page 79,Basic quality Measurement,2019/2/19,ASM Pacific Technology Ltd. 2009,page 80,Basic quality Measurement,2019/2/19,ASM
23、 Pacific Technology Ltd. 2009,page 81,Basic quality Measurement,键合工艺质量控制测试 Visual Inspection(目检) Bond Shear(推球) Wire Pull(拉线) Wire peel(第二焊点拉线) IR microscopy(红外线显微镜) Cross-section(抛面分析) Chemical etch(化学腐蚀)体视显微镜缺陷目检: missing wire broken wiremisbond bad looplifted bond second bond impressionweak/smash
24、ed bond pad/lead bond placementforeign metter die damage,2019/2/19,ASM Pacific Technology Ltd. 2009,page 82,Bond Shear,Bond Shear破坏性测试 第一焊点推球测试焊点的键合强度 推球测试会在最弱的结合面剪切第一焊 点(金球,金铝结合面,焊点金属层与芯 片基底面)所以推球后需观察推落模式. 该测试是球焊工艺的业界标准测试项目,2019/2/19,ASM Pacific Technology Ltd. 2009,page 83,Bond Shear,失效模式 CODE NO.
25、 Ball Lift 1 Ball Shear 2 Bond Pad Lift 3 Cratering 4 * Wire Shear/Others 5 Notes: * 无效推球,有效推球模式 1.Ball lift - 推球后小于或等于的残金残留在焊区金属层 2. Ball shear -大于或等于的残金残留在焊区金属层 3. Pad metal lift -焊区金属粘附在金球上与芯片基底脱落脱落 4. Cratering - 芯片基底硅层或氧化层部分损坏或脱落,无效推球模式 5. Wire shear & other interferences -推刀推线或其它 - 推刀推过球上部或未推掉
26、球的全部 - 推球过程中推刀接触芯片表面 - 推球结束后推刀划到芯片 - 其它,2019/2/19,ASM Pacific Technology Ltd. 2009,page 84,Bond Shear失效模式,2019/2/19,ASM Pacific Technology Ltd. 2009,page 85,Bond Shear失效模式,2019/2/19,ASM Pacific Technology Ltd. 2009,page 86,单位面积推球强度,2019/2/19,ASM Pacific Technology Ltd. 2009,page 87,Wire Pull,拉线测试(Wi
27、re Pull)是常用的控制键合线弧和工艺质量的测试法,它 是破坏性 测试,拉断点为线弧的最弱位置拉线钩 子放置位置及线弧形状会 影响测试结果,在下述情况下拉线力会降低: 钩子越靠近线弧中点,拉力越小 线弧越低,拉力越小 线弧越长,拉力越小 第一焊点与第二焊点高度差别越大,拉力越 小,2019/2/19,ASM Pacific Technology Ltd. 2009,page 88,Wire Pull,2019/2/19,ASM Pacific Technology Ltd. 2009,page 89,Wire Pull,2019/2/19,ASM Pacific Technology Lt
28、d. 2009,page 90,Wire Pull,2019/2/19,ASM Pacific Technology Ltd. 2009,page 91,Wire Pull,2019/2/19,ASM Pacific Technology Ltd. 2009,page 92,IR Microscopy & Cross-section,IR Microscopy 利用红外线从试样背面检测可得到焊区 金铝intermetallic的图形并可判断其质 量当研究新工艺(如焊区金属层改变, 不同频率的焊线机换能杆)需做 特性化分析时,此方法比推球测试更能 反映结合面的键合质量 非破坏性测试 只适用于工程
29、分析及工艺特性化分析 因其试样的准备耗费时间故不适用于在线监控,Cross-section 研磨塑封后的芯片,露出焊点后抛光然 后在显微镜下观察,可以看到intermetallic 的厚度使用IR microscopy method观察 到的是该区域的面积 只适用于工程分析,非常耗费时间,2019/2/19,ASM Pacific Technology Ltd. 2009,page 93,Cross-section,Ball bond,Stitch Bond,2019/2/19,ASM Pacific Technology Ltd. 2009,page 94,Chemical Etch,Che
30、mical Etch化学腐蚀是一项很重要的分析,将焊区的金属铝腐蚀掉后,可观察到 intermetallic的覆盖率,以及焊区金属 层下面电路是否有损伤 该测试作为工程分析手段用来评估新的 焊区金属工艺,新型金丝,新键合机等等,2019/2/19,ASM Pacific Technology Ltd. 2009,page 95,Intermetallic Compounds,Intermetallic Compounds - 焊点实际是由Intermetallic将两种金属 键合在一起 - Intermetallic形成依赖于金属相接触的 时间和温度 - 键合点的强度和可靠性通常决定于金球 和焊区金属间Intermetallic面积 - 焊区不受污染是形成高质量 Intermetallic的必要条件,2019/2/19,ASM Pacific Technology Ltd. 2009,page 96,WIRE BOND主要不良因素分析,2019/2/19,ASM Pacific Technology Ltd. 2009,page 97,WIRE BOND主要不良因素分析,2019/2/19,ASM Pacific Technology Ltd. 2009,page 98,WIRE BOND主要不良因素分析,End Thanks,