Late Component Change Notifications Handling in Turnkey Sourcing
Lock bills of materials contractually and require automated feeder verification to eliminate unannounced component substitutions in turnkey electronics sourcing.
Moisture Sensitive Devices
Meaning
Semiconductor components housed in plastic packages that absorb ambient humidity require specialized handling to prevent thermal damage during reflow soldering. Active integrated circuits, sensors, and led modules are typical examples of moisture sensitive devices that demand strict environmental controls on the assembly floor. Proper tracking of these components is essential to ensure they remain dry prior to board mounting.
Failure Mechanism
Entrapped atmospheric moisture inside the plastic encapsulation turns to steam when subjected to high-temperature reflow ovens. This rapid expansion causes internal delamination, wire bond fractures, or visible cracks in moisture sensitive devices. Because these defects are often hidden beneath the package surface, they can bypass standard visual inspection and lead to early field failures.
Protective Packaging
Component manufacturers ship these sensitive parts in sealed moisture-barrier bags containing active desiccant and a humidity indicator card. Quality inspectors check the status of this card immediately upon opening the bag to verify that moisture sensitive devices have not been exposed to excessive humidity during transport. If the card indicates moisture exposure, the parts must undergo a low-temperature baking cycle before they can be released to the assembly line.
This procedure removes the absorbed water without causing thermal oxidation of the termination leads.
Sourcing Impact
Purchasing departments must select suppliers that offer robust protective packaging and accurate shelf-life ratings. Warehouse operations must allocate climate-controlled storage cabinets to house these components.