Authored By:
Maurice Dore
Valeo CDV
Summary
Increasing complexity of critical components, designs, manufacturing processes and harsher test conditions continues to challenge the automotive electronics development life cycle. The drive for right first time makes it critical to pre-empt potential board level issues as early as possible to avoid costly and time-consuming repeat validations.
Historically, solder interconnection separation due to Coefficient of Thermal Expansion (CTE) Mismatch between the components and Printed Circuit Board (PCB) were the most prolific failures. With increasingly high density interconnection designs, advanced packaging, increased localised self heating, additional sources of thermomechanical stress are introducing more complex failures. It is important to consider the full design and each element's thermomechanical behaviour across relevant stress load conditions.
Conclusions
Thermomechanical Stress is an ever-increasing concern with advanced packaging, complex designs and increasing functionality of automotive electronics. Many sources of thermomechanical stress are unintentionally introduced due to product designs such as mirroring, underfill, thermal interface materials and associated curing process steps. Understanding the external influence is critical to implement corrective actions.
Initially Published in the SMTA Proceedings
|
