Technical Library | 2023-08-16 18:48:50.0
One of our aerospace customers was looking to automate a few manual operations and asked for suggestions. This customer specializes in assemblies for inflight connectivity for commercial airlines and low orbit satellites. The dispensing process included the application of bonding to the sides of large and small components (4-axis) and the ability to cope with the changing viscosity during processing. The material used was EC-2216 B/A Two Part Epoxy and the largest board size was 12"x10"
Technical Library | 2024-06-23 22:03:59.0
The melting temperatures of most lead-free solder alloys are somewhat higher than that of eutectic Sn/Pb solder, and many of the alloys tend to wet typical contact pads less readily. This tends to narrow down the fluxing and mass reflow process windows for assembly onto typical organic substrates and may enhance requirements on placement accuracy. Flip chip assembly here poses some unique challenges. The small dimensions provide for particular sensitivities to wetting and solder joint collapse, and underfilling does not reduce the demands on the intermetallic bond strength. Rather, the need to underfill lead to additional concerns in terms of underfill process control and reliability. Relatively little can here be learned from work on regular SMT components, BGAs or CSPs.
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