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NOR: Heat and No Heat Extraction Methods for Flash Memory Units

NOR: Heat and No Heat Extraction Methods for Flash Memory Units

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There are two ways to extract a unit from the application board—with heat and without heat.

But which one should be used?

The heat extraction method uses controlled heat to extract a single unit from a system board. Typically, this method is used on units with no under-fill, board level devices such as FBGA, TSOP, and PQFR package types. Before unit extraction, the application board has to be submitted to bake, to drive moisture from the unit. Otherwise, during heat extraction, the package might crack, aka “the popcorn effect”. JEDEC-STD-033 shows a table with recommended bake time for different package types.

Now, the no heat extraction method uses mechanical saws to cut the device away from the board. This technique preserves the integrity of the unit without heat related damage and electrical/physical alternation. This method reduces the risk of package overheating, delamination, and die cracking.

Regardless of the method used, extracted devices need to be polished and carefully scraped to remove any remaining residue before it can be reballed and reflowed in other devices.

For a step-by-step guide on each extraction method and follow up procedures, please reply below and let our experts help guide you!