Board Level-Component Solder Joints Normalized Crack Severity Index of Solid-State Drive With Different Reliability Temperature Cycle Test Profiles

In the realm of electronic device manufacturing, one persistent challenge is the lack of a universal TCT (Temperature Cycle Test) solder joints crack assessment that is suitable for all types of electronic components. This gap becomes particularly complex when multiple components are assembled into a single board. Therefore, this paper proposed an approach by normalizing the solder joints cracks, index $\eta $ value as benchmarking value for solder joint cracks in components following TCT. This work used four types of components include controller, NAND, double data rate random-access memory (DDR-RAM) and power management integrated circuit (PMIC). All of these components subjected to three different TCT conditions (A) −40 to $85~{^{^{\circ }} }$ C, 10 mins soak, 12.5 mins ramp, 500 cycles, (B) 0 to $100~{^{^{\circ }} }$ C, 15 mins soak, 15 mins ramp, 750 cycles and (C) 0 to $100~{^{^{\circ }} }$ C, 15 mins soak, 15 mins ramp, 900 cycles to determine relative severity of the SSD design, and its critical components solder joint performance. Solder joints crack percentage is calculated from inspection post DnP and analysed to compare the severity. The normalize solder joints, index $\mathrm {{\eta }\ }$ were calculated and used to analyse all the components post TCT. It was found that TCT profile C is more stringent with solder joint cracks $4.1x$ higher than TCT profile A and $2.5\mathrm {\ x}$ higher than TCT profile B. The highest index $\eta $ value of 5.2 from TCT profile C indicates that it is the most stringent of all tested TCT profiles, compared to TCT profile B at 2.67 and TCT profile A at 1.13. The findings from this study provide valuable insights into selecting effective TCT profiles, allowing for optimized testing procedures that save time and resources. This approach is particularly beneficial for specific components, including controller, NAND, DDR-RAM and PMIC packages. Furthermore, normalizing solder joint cracks using the index $\eta $ value as a benchmarking metric can be applied to other types of electronic components.