TN1188

Recommended storage instructions

DocID026684 Rev 2

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4.2

Clay desiccant dimensioning

Theoretical calculations and experimental tests show that there must be at least 2 grams of

clay desiccant for 4 trays. Each bulk includes 4 trays = 1 bag of desiccant = 2 grams.

In case an inner bag is opened, the quantity of desiccant should be increased to 4

grams to ensure the proper humidity level.

5

Recommended storage instructions

ST aerospace die products are packed in a clean-room environment. It is recommended to

store these products in a similar environment. The following key storage precautions

should be observed:



The die must be maintained in a filtered nitrogen atmosphere until removed for

assembly.



The moisture content of the storage facility must be maintained at 30 percent ±10

percent relative humidity.



Electrostatic discharge (ESD) damage precautions are necessary during handling.

The die must be in an ESD-protected environment at all times for inspection and

assembly. Dice contained in waffle trays can remain in storage for up to one year

under these conditions.

If a visual inspection is required, it is recommended to repack the dice immediately

afterward, following the recommendations above, or to bond them immediately.

6

Quality requirements

Trays use for packing must not be damaged (i.e. cracked, broken or chipped.)

A change of the waffle pack is considered a minor change, which ST will only notify the

customer about. ST standard rules on product change notifications (PCNs) apply only to

changes affecting the die itself.