{"title":"无铅焊料互连中钎料/IMC界面循环损伤过程模拟的扩展粘结区模型","authors":"A. Yamin, N. Shaffiar, W. K. Loh, M. Tamin","doi":"10.1109/IEMT.2012.6521786","DOIUrl":null,"url":null,"abstract":"The current formulation of stress- and energy-based cohesive zone model (CZM) is extended to account for load reversals. Cyclic degradation of solder/IMC interface properties, namely penalty stiffness, strengths and critical energy release rates follows power-law functions of fatigue cycles. Performance of the extended CZM is examined using finite element (FE) simulation of a single Sn-4Ag-0.5Cu (SAC405) solder interconnect specimen. Strain rate-dependent response of the solder is represented by unified inelastic strain equations (Anand's model) with optimized model parameters for SAC405 solders. The 3D FE model of the specimen is subjected to cyclic relative displacement (Δδ = 0.003 mm, R = 0) so as to induce shear-dominant fatigue loading. Results show that interface crack initiated at the leading edge of the solder/IMC interface on the tool side of the assembly after 22 cycles have elapsed. Bending stress component induced by the solder stand-off height dominates the interface damage process. A straight interface crack front is predicted indicating the relatively brittle nature of the SAC405/Cu6Sn5 interface. The extended formulation of the CZM to account for load reversals has demonstrated the ability to describe the progressive solder/IMC interface damage process consistent with the mechanics of relatively brittle interface fracture.","PeriodicalId":315408,"journal":{"name":"2012 35th IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":"{\"title\":\"Extended cohesive zone model for simulation of solder/IMC interface cyclic damage process in Pb-free solder interconnects\",\"authors\":\"A. Yamin, N. Shaffiar, W. K. Loh, M. Tamin\",\"doi\":\"10.1109/IEMT.2012.6521786\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The current formulation of stress- and energy-based cohesive zone model (CZM) is extended to account for load reversals. Cyclic degradation of solder/IMC interface properties, namely penalty stiffness, strengths and critical energy release rates follows power-law functions of fatigue cycles. Performance of the extended CZM is examined using finite element (FE) simulation of a single Sn-4Ag-0.5Cu (SAC405) solder interconnect specimen. Strain rate-dependent response of the solder is represented by unified inelastic strain equations (Anand's model) with optimized model parameters for SAC405 solders. The 3D FE model of the specimen is subjected to cyclic relative displacement (Δδ = 0.003 mm, R = 0) so as to induce shear-dominant fatigue loading. Results show that interface crack initiated at the leading edge of the solder/IMC interface on the tool side of the assembly after 22 cycles have elapsed. Bending stress component induced by the solder stand-off height dominates the interface damage process. A straight interface crack front is predicted indicating the relatively brittle nature of the SAC405/Cu6Sn5 interface. The extended formulation of the CZM to account for load reversals has demonstrated the ability to describe the progressive solder/IMC interface damage process consistent with the mechanics of relatively brittle interface fracture.\",\"PeriodicalId\":315408,\"journal\":{\"name\":\"2012 35th IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT)\",\"volume\":\"66 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2012-11-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"2\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"2012 35th IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT)\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1109/IEMT.2012.6521786\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"2012 35th IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/IEMT.2012.6521786","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 2
摘要
将目前基于应力和能量的黏聚区模型(CZM)扩展到考虑荷载逆转。焊料/IMC界面性能的循环退化,即惩罚刚度、强度和临界能量释放率遵循疲劳循环的幂律函数。通过对单个Sn-4Ag-0.5Cu (SAC405)焊料互连试件的有限元模拟,研究了扩展后的CZM的性能。采用统一的非弹性应变方程(Anand模型)表示随应变率变化的焊料响应,并对SAC405焊料优化了模型参数。试件的三维有限元模型受循环相对位移作用(Δδ = 0.003 mm, R = 0),从而诱发剪切为主的疲劳载荷。结果表明,经过22次循环后,在组件的工具侧焊料/IMC界面的前缘开始出现界面裂纹。由焊料隔离高度引起的弯曲应力分量主导了界面损伤过程。结果表明,SAC405/Cu6Sn5界面具有较脆的脆性。考虑载荷逆转的CZM扩展公式已经证明能够描述与相对脆性界面断裂力学一致的渐进焊料/IMC界面损伤过程。
Extended cohesive zone model for simulation of solder/IMC interface cyclic damage process in Pb-free solder interconnects
The current formulation of stress- and energy-based cohesive zone model (CZM) is extended to account for load reversals. Cyclic degradation of solder/IMC interface properties, namely penalty stiffness, strengths and critical energy release rates follows power-law functions of fatigue cycles. Performance of the extended CZM is examined using finite element (FE) simulation of a single Sn-4Ag-0.5Cu (SAC405) solder interconnect specimen. Strain rate-dependent response of the solder is represented by unified inelastic strain equations (Anand's model) with optimized model parameters for SAC405 solders. The 3D FE model of the specimen is subjected to cyclic relative displacement (Δδ = 0.003 mm, R = 0) so as to induce shear-dominant fatigue loading. Results show that interface crack initiated at the leading edge of the solder/IMC interface on the tool side of the assembly after 22 cycles have elapsed. Bending stress component induced by the solder stand-off height dominates the interface damage process. A straight interface crack front is predicted indicating the relatively brittle nature of the SAC405/Cu6Sn5 interface. The extended formulation of the CZM to account for load reversals has demonstrated the ability to describe the progressive solder/IMC interface damage process consistent with the mechanics of relatively brittle interface fracture.