RF Micro Devices Inc.

7628 Thorndike Road, Greensboro, NC 27409-9421

DS131029

For sales or technical support, contact RFMD at +1.336.678.5570 or customerservice@rfmd.com.

RF MICRO DEVICES

trademarks, and registered trademarks are the property of their respective owners. ©2013, RF Micro Devices, Inc.

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Assembly Notes

Die Storage



Individual bare die should be held in appropriately sized ESD waffle trays or ESD GEL packs.



Die should be stored in CDA/N2 cabinets and in a controlled temperature and humidity environment.

Die Handling



Die should only be picked using an automated or semi-automated pick system and an appropriate pick tool.



Pick parameters will need to be carefully defined so as not to cause damage to either the top or bottom die surface.



GaN HEMT devices are ESD sensitive materials. Please use proper ESD precautions when handling devices or

evaluation boards.



RFMD does not recommend operating this device with typical drain voltage applied and the gate pinched off in a high

humidity, high temperature environment.

Caution: The use of inappropriate or worn-out ejector needle and improper ejection parameter settings can cause die backside

tool marks or micro-cracks that can eventually lead to die cracking.

Die Attach

There are two commonly applied die attach processes: adhesive die attach and eutectic die attach. Both processes use special

equipment and tooling to mount the die.

EUTECTIC ATTACH



80/20 AuSn preform, 0.5mil to 1mil thickness, made from virgin melt gold.



Pulsed heat or die scrub attach process using automated or semi-automatic equipment.



Attach process carried out in an inert atmosphere.



Custom die pick collets are required that match the outline of the die and the specific process employed using either

pulsed, fixed heat, or scrub.



Maximum temperature during die attach should be no greater than 320°C and for less than 30 seconds.



Key parameters that need to be considered include: die placement force, die scrub profile and heat profile.



Minimal amount of voiding is desired to ensure maximum heat transfer to the carrier and no voids should be present

under the active area of the die.



Voiding can be measured using X-ray or Acoustic microscopy.



The acceptable level of voiding should be determined using thermal modeling analysis.

ADHESIVE ATTACH



High thermal silver filled epoxy is dispensed in a controlled manner and die is placed using an appropriate collet.

Assembled parts are cured at temperatures between 150°C and 180°C.



Always refer to epoxy manufacturer's data sheet.



Industry recognized standards for epoxy die attach are clearly defined within MIL-883.