What can be said about reliability of these assemblies? |
|
|
Answer: This is an extremely important question. No testing has been done yet, but reliability experts who have seen the concept have very positive expectations. The reduction in the number and type of interconnections is a big step in the right direction. As world renowned reliability expert Werner Engelmaier observes:
“The big difference is that there are no connections subject to creep-fatigue, since nothing in this interconnection technology requires a low melting temperature, and thus operating temperatures will be way below a homologous temperature of Th=0.5 where creep becomes significant. The fatigue, to the extent it will occur will be all in high-cycle fatigue, something just not possible with solders where all fatigue is low-cycle fatigue in combination with creep.”
Elimination of all soldering issues, especially lead-free issues is a key benefit, Actually, the reverse order processing concept eliminates all the industry-recognized solder-joint vulnerabilities. Conventional PWB plated-though-hole vias, as mentioned earlier are most vulnerable to high temperature excursions. In contrast, because all electrical interconnections become solid monolithic, interface-free, and because processing takes place at near room temperature, temperature induce risks are reduced. Certainly, these benefits must be demonstrated, tested, qualified, and validated. These efforts are on-going and planned. |
|
Powered by
KBPublisher (Knowledge base software)