5

Process recommendations

To ensure a consistent manufacturing process it is strongly advised to comply with following recommendations:

•

The recommended pick-up area for the IMP34DT05 package must be defined using the worst case (ie. no

device alignment during picking process). This area has been defined considering all the tolerances of the

components involved (reel, package, sound inlet). Picker tolerance shall be considered as well.

•

To prevent damage to the MEMS membrane or incorrect pick-up and placement, do not pick up the

component on the inlet area

•

For the package outline please refer to Figure 7. Carrier tape with microphone (top view). Nozzle shape,

size, and placement accuracy are the other key factors to consider when deciding on the coordinates for the

picking.

•

Device alignment before picking is highly recommended.

•

A vacuum force greater than 7 psi must be avoided

•

1 kPa = 0.145 psi (lb/in²) = 0.0102 kgf/cm² = 0.0098 atm

•

MSL (moisture sensitivity level) Class 3

•

Maximum of 3 reflow cycles is recommended

•

All recommended dimensions (device safe-picking area) do not include the pick-and-place equipment

tolerances

To have a safe pick-up "by design", ST strongly advises an ad hoc nozzle.

The following picker ensures that the holes for the vacuum and the air stream are ALWAYS away from the

porthole of the device (4 vacuum ports located at each corner of the device).

The recommended nozzle also has a recess, in the form of a cross, which guarantees that the porthole is always

left at atmospheric pressure. By using the recommended nozzle, the membrane will not suffer any sudden air

disturbances during the picking or placing of the devices in the tape and reel.

IMP34DT05

Process recommendations

DS12725 - Rev 3

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