Key takeaways
A standard failure analysis runs six steps: symptom confirmation -> visual inspection -> non-destructive testing (X-ray / ultrasound) -> electrical re-measurement -> destructive analysis (cross-section / dye-and-pry / SEM) -> root-cause report. The evidence chain requires a record at every step and reproducible conclusions; comparing the failed unit against good units from the same lot shortens localisation considerably.
When a failed unit reaches the laboratory, the usual request is "tell me what broke". Failure analysis is worth more than that — it has to answer why it broke and how to stop it happening again. That takes a complete evidence chain.
1. The standard six-step path
- Confirm the symptom: the failure mode, the conditions under which it occurs, the proportion, the timing — the more specific the input, the shorter the path
- Visual inspection: photograph and record burning, cracks, contamination and discolouration — see what can be seen without damage first
- Non-destructive testing: X-ray for solder joints and internal defects, ultrasound for delamination and voids
- Electrical re-test: reproduce, or partly reproduce, the failure under known conditions and pin down the failure point
- Destructive analysis: cross-section, dye penetrant, SEM/EDS to examine the interface, plating and metallurgical layer
- Root cause report: failure mode plus mechanism plus evidence plus improvement recommendations
2. Why the order cannot be shuffled
Skipping straight to a cross-section destroys the scene: a cross-section gives you one plane, whereas the clues — crack direction, contamination distribution — are usually lost in the process of cutting. Every step is potentially the crime scene for the next one, and that is exactly what the evidence chain means.
3. What to bring when submitting samples
Keep the failed unit in its original state (do not dismantle, abrade or wash it), include known-good units from the same batch for comparison, describe the symptom (when, under what conditions, in what proportion) and list what has already been checked. Analysis with a reference unit is usually far more efficient — without a baseline there is no such thing as an "anomaly".
4. How the report gets used
A competent root cause report feeds straight into an 8D: problem description, root cause, corrective action and verification method all line up. A report that says only "solder joint cracked", by contrast, moves improvement nowhere.
Turnaround time is arranged according to the actual project. You are welcome to state your target date when submitting samples; we will check it against the current schedule, confirm a feasible plan with you, and update you at each milestone.
