Tombstoning is a well known issue for SMT soldering and is usually caught at post solder visual inspection. However, at times the effect is a subtle lifting at one end of the component as was the case in this example of an SMD inductor. The failure was a high resistance in the associated signal net that wasn’t detected until final assembly and testing of the product.
This is a BSE SEM image of a microsection of the device as soldered on the PCBA.
The high resistance was caused by a failure of the original solder reflow process to wet the termination, which caused “tomb stoning” of the inductor.
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