Wafer Level Chip Scale Package Failure Mode Prediction using Finite Element Modeling

Publikation: Beitrag in Buch/Konferenzbericht/Sammelband/GutachtenBeitrag in KonferenzbandBeigetragenBegutachtung



In this study a Finite Element Model (FEM) was designed in order to predict the reliability behavior of 7×7 mm2 Wafer Level Chip Scale Packages (WLCSP) during board level thermal cycling tests, considering different solder material models for SAC405 and SACQ interconnects. A significant difference in plastic strains within the package was observed for a variety of solder material models: Compared to SACQ interconnects an approximate 70% plastic strain increase in solder and a 35% plastic strain reduction in the polyimide passivation layer was observed for packages with SAC405 interconnects. Simulations were verified by experimental thermal cycling test data done at board level. During thermal cycling, packages showed different failure modes depending on the interconnect material used in the package. Also, SAC405 showed earlier failure. Maximum strain obtained from simulations was used as an indicator of potential failure locations for the solder alloy and polyimide layer. The proposed model setup enables precise simulation results, which are well aligned with the actual experimental findings on the behavior of WLCSP with SAC405 and SACQ interconnects.


Titel2023 IEEE International Reliability Physics Symposium, IRPS 2023 - Proceedings
Herausgeber (Verlag)IEEE
ISBN (elektronisch)978-1-6654-5672-2
ISBN (Print)978-1-6654-5673-9
PublikationsstatusVeröffentlicht - 30 März 2023


ReiheIEEE International Reliability Physics Symposium Proceedings


Titel2023 IEEE International Reliability Physics Symposium (IRPS)
Dauer26 - 30 März 2023
OrtMonterey, CA, USA

Externe IDs

Scopus 85160442774
Mendeley 4f78db3e-37e9-3ecd-9f06-c571ca268dd1
ORCID /0000-0002-0757-3325/work/139064823


ASJC Scopus Sachgebiete


  • Semiconductor device modeling, Metals, Polyimides, Materials reliability, Predictive models, Finite element analysis, Behavioral sciences, WLCSP, failure mode, finite element modeling, lead-free solder, plastic strain