Authored By:
Guenther Mayr
AT&S AG
Summary
In light of new process and product technologies in the field of embedded components, questions arise with respect to advantages and potential disadvantages to standard SMT component placement when considering reliability.
This paper is the second part in a progressively complex series of comparative analyses, testing the reliability of standard SMT components in comparison to their embedded counterparts.
In the initial round of comparative tests, we analyzed passive components. In this second part we will compare the performance of similarly specified embedded dies and standard surface mounted CSPs which are designed to simulate an active component ("dummies") in terms of interconnectivity.
The applied reliability tests shall include:
Drop Test per JEDEC JESD22-B111: 1500g / 0.5ms
Thermal cycle testing (TCT) per JEDEC JESD22-A104: -40 degrees C / +125 degrees C
Bend Testing - Based on the IPC/JEDEC 9702 (Monotonic Bend Characterization of Board-Level Interconnects)
With these tests, as with the initial paper on embedded passives, we aim to define possible limitations, advantages, disadvantages and areas of functional application which are relevant to this direct comparison. With the addition in this study of one mechanical bend test we hope to introduce a more well-rounded picture of the reliability one should expect for different instances and component placement methodologies.
As the usage, as well as fields of application, of embedded components increases in part due to more stable and refined methods of manufacturing, it is worthwhile to examine them based on industry norms and standards as a source of comparison to traditional manufacturing methods. Part of this analysis is therefore to investigate the feasibility of employing such standards in the context of embedded components. This investigation, in turn, should offer us a holistic perspective to other current industry projects, such as the EU-funded "Hermes".
Conclusions
To summarize, there were visible reliability advantages for embedded components under the production and testing methods described. These advantages, at least with these components and array, are mainly found in the reduction of deviation to a rigid board's neutral axis. In terms of thermal reliability we did see clear advantages for ECs versus SMD.
Initially Published in the IPC Proceedings
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