Abstract
To meet the requirement of the high I/O and fine-pitch interconnects, the conventional insertion-mount socket for central processing unit (CPU) has been changed to surface-mount one with ball grid array. The solder ball joint reliability of the socket used in the CPU assembly becomes very important.
| Original language | English |
|---|---|
| Pages (from-to) | 693-703 |
| Number of pages | 11 |
| Journal | Journal of Mechanics |
| Volume | 37 |
| DOIs | |
| State | Published - 2021 |
Bibliographical note
Publisher Copyright:©, and numerically by a finite element method (FEM). The validated FEM results have suggested that maximum stress of solder balls increases almost linearly with decreasing the backplate thickness under mechanical loading during the CPU assembly, but is insensitive to the backplate thickness under thermal loading during the thermal cycling. It is also found that the residual (bending) strain on the PCB proportional to the maximum von Mises stresses of solder joints (or balls) can be used as a key parameter to correlate with the solder joint failures or cracks during the thermal cycling. Overall, experimental and FEM results in this study reveal that solder joint reliability in the CPU assembly during thermal cycling can be improved by adopting the thicker reinforced backplate.
Keywords
- Backplate
- CPU assembly
- Solder Joint Reliability
- Thermal Cycling