NBB-310
Die Attach
• The die attach process mechanically attaches the die to the circuit substrate. In addition, the utilization of proper die
attach processes electrically connect the ground to the trace on which the chip is mounted. It also establishes the
thermal path by which heat can leave the chip.
• Die should be mounted to a clean, flat surface. Epoxy or eutectic die attach are both acceptable attachment meth-
ods. Top and bottom metallization are gold. Conductive silver-filled epoxies are recommended. This procedure
involves the use of epoxy to form a joint between the backside gold of the chip and the metallized area of the sub-
strate.
• All connections should be made on the topside of the die. It is essential to performance that the backside be well
grounded and that the length of topside interconnects be minimized.
• Some die utilize vias for effective grounding. Care must be exercised when mounting die to preclude excess run-out
on the topside.
Die Wire Bonding
• Electrical connections to the chip are made through wire bonds. Either wedge or ball bonding methods are accept-
able practices for wire bonding.
• All bond wires should be made as short as possible.
Notes
1RFMD Document #6000152 - Die Product Final Visual Inspection Criteria. This document provides guidance for die inspec-
tion personnel to determine final visual acceptance of die product prior to shipping to customers.
2RFMD takes precautions to ensure that die product is shipped in accordance with quality standards established to minimize
material shift. However, due to the physical size of die-level product, RFMD does not guarantee that material will not shift dur-
ing transit, especially under extreme handling circumstances. Product replacement due to material shift will be at the discre-
tion of RFMD.
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
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