Quantitative evaluation of PI-RDL interfacial delamination in fan-out wafer-level packaging during unbiased highly accelerated stress test

Wu, Wenyu1; Zhao, Wenzhe2; Chen, Kai1; Ma, Baoguang2; Lu, Dong3; Wang, Ke4; Wu, Jingshen1

2024-10-01

10.1016/j.engfailanal.2024.108668

ENGINEERING FAILURE ANALYSIS   影响因子和分区

1350-6307

1873-1961

Fan-Out Wafer-Level Packaging (FOWLP) is increasingly utilized for its superior performance, facilitated by flexible heterogeneous integration. Despite its advantages, the interface between Polyimide (PI) and Redistribution Layers (RDL) is susceptible to significant vulnerabilities, notably delamination. This study introduces a quantitative method to assess PI-RDL interface delamination in FOWLP under unbiased Highly Accelerated Stress Tests (uHAST), a standard approach in accelerated reliability testing characterized by high humidity and temperature. Central to our methodology is the development of a time-temperature-moisture equivalencebased creep constitutive model, which significantly enhances our understanding of the impact of temperature and moisture on creep behavior. Furthermore, we have developed an innovative "open moisture absorption" method for preparing samples for four-point bending tests, enabling precise quantification of the time-induced degradation of PI-RDL interfacial fracture toughness under saturated conditions. Our comprehensive finite element model integrates moisture diffusion, the newly developed creep constitutive model, and solid mechanics to accurately simulate the accumulation of strain energy release rate during uHAST, facilitating precise predictions of delamination initiation times in FOWLP. Experimental validation under two uHAST conditions-130 degrees C/85 %RH for 96 h and 110 degrees C/85 %RH for 264 h-demonstrates the effectiveness of our approach, predicting the delamination initiation time at the PI-RDL interface with over 80 % accuracy. This predictive methodology is pivotal in enhancing the structural optimization and extending the service life of FOWLP in varied environmental conditions.

Mechanical engineering Electronic packaging Polymers Finite elements analysis Environmental-assisted cracking Temperature and humidity induced creep Material selection

SCI ; EI

英语

通讯

Department of Science and Technology of Guangdong Province[2023B0101020004]

Engineering ; Materials Science

Engineering, Mechanical ; Materials Science, Characterization & Testing

WOS:001276029600001

PERGAMON-ELSEVIER SCIENCE LTD

20243016749568

Bending tests ; Constitutive models ; Creep ; Ductile fracture ; Electronics packaging ; Fracture toughness ; Moisture ; Strain energy ; Strain rate ; Structural optimization

Strength of Building Materials; Test Equipment and Methods:422 ; Mathematics:921 ; Optimization Techniques:921.5 ; Numerical Methods:921.6 ; Mechanics:931.1 ; Materials Science:951

ENGINEERING

Web of Science

1.Hong Kong Univ Sci & Technol Guangzhou, Thrust Smart Mfg, Syst Hub, Guangzhou 511400, Peoples R China
2.Guangzhou HKUST FOK YING TUNG Res Inst, Ctr Engn Mat & Reliabil, Guangzhou 511400, Peoples R China
3.Hong Kong Univ Sci & Technol Guangzhou, Lab Future Technol, Guangzhou 511400, Peoples R China
4.Southern Univ Sci & Technol, Sch Syst Design & Intelligent Mfg, Shenzhen 518055, Peoples R China

Wu, Wenyu,Zhao, Wenzhe,Chen, Kai,et al. Quantitative evaluation of PI-RDL interfacial delamination in fan-out wafer-level packaging during unbiased highly accelerated stress test[J]. ENGINEERING FAILURE ANALYSIS,2024,164.

Wu, Wenyu.,Zhao, Wenzhe.,Chen, Kai.,Ma, Baoguang.,Lu, Dong.,...&Wu, Jingshen.(2024).Quantitative evaluation of PI-RDL interfacial delamination in fan-out wafer-level packaging during unbiased highly accelerated stress test.ENGINEERING FAILURE ANALYSIS,164.

Wu, Wenyu,et al."Quantitative evaluation of PI-RDL interfacial delamination in fan-out wafer-level packaging during unbiased highly accelerated stress test".ENGINEERING FAILURE ANALYSIS 164(2024).