DocID025184 Rev 1

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AN4351

Glue dispensing guidelines and recommended practice

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Glue dispensing guidelines and recommended

practice

2.1

Storage and use of silver filled conductive glue

•

The silver filled glues are perishable material and needs to be stored with care. The

shipping container must be designed to protect the material in transit for up to 2 days.

Use carbon ice to store the material at minus 40 °C (or other temperature versus TDS

supplier).

•

Immediately upon receipt, unpack the shipping container and freeze the material at

minus 40 °C (or other temperature versus TDS supplier). Syringes containing silver

filled glues must be stored vertically with their caps on.

•

Glue shelf life at minus 40 °C depends on the glue material; please check the shelf life

information with the supplier.

•

It is not recommend to refreeze used material and to redistribute or repack glues pack

in syringes because syringes are packaged by special techniques to ensure no air

bubbles are trapped inside the syringe; it is instead recommend to choose smaller

syringe size like 5 cc or 3 cc.

For equipment set up purposes (and some engineering runs), thawed materials staying at

room temperature of less than 4 hours (including thawing time) can be refrozen 3 times

maximum. This refrozen material must not be used for production runs due to potential

reliability and quality risk (mechanical and electrical contact reliability can be downgraded).

For production runs, silver filled conductive glues can usually be used during 2 hours

without the need of adjusting and correcting input parameters (pressure, time). Beyond 2

hours, it is recommended to check and adjust input parameters to assure the same

dispensing quantity.

2.2

Receiving inspection and preparation for use

Silver conductive glues should be removed from cold storage and thawed at room

temperature.

Immediately, do not remove back end cap from the syringe, remove front end cap and install

needle according to Table 1.

The required thawing time will be dependent upon the syringe size; a good indication that

the material is ready is when condensation on the syringe disappears. Typical time is from

30 minutes to 1 hour for 5 cc syringe size. Thawing must be done with the syringes standing

vertically.

Never use heat to accelerate the thawing. Do not place syringes near any heat source

(ovens, furnaces) or immerse in hot and warm water. These practices will adversely affect

performance.

Syringes should be inspected prior to use; any evidence of separation (material, plunger),

large air voids or discoloration or dark aspect are indications of thermal excursions

rendering the syringe unfit for use.