Imbedded Components: Ready for Mainstream?

Casey H. Cooper, Mark T. McMeen, Jim D. Raby
STI Electronics, Inc., Madison, AL USA

Military and aerospace electronics providers continue to push the technological envelope to design and manufacture leading edge electronics for today's DOD users. Current design problems are not driven by circuit design capabilities but by an inability to reliably package these circuits within size and weight requirements (SWAP) outlined by the system level specifications.

Innovative packaging techniques are required in order to meet the increasing size, weight, power, and reliability requirements of the DOD without sacrificing electrical, mechanical, or thermal performance. Emerging technologies such as those imbedding components within organic substrates have proven capable of meeting and exceeding these design objectives for meeting size, weight and power requirements. The ability to design smaller, lighter and less power circuit board assemblies that are more robust than conventional SMT boards has a future in the electronics of tomorrow.

Imbedded Component/Die Technology (IC/DT) addresses these design challenges through imbedding both active and passives into cavities within a multi-layer printed circuit board to decrease the surface area required to implement the circuit design and increase the robustness of the overall assembly.

This paper discusses the design methodology, and validation/test data gathered during the implementation of IC/DT in a mixed signal prototype. The prototype designed and assembled using IC/DT processes was subjected to reliability testing and ultimately demonstrated in a test flight. The results from this testing as well as the future designs utilizing IC/DT are presented.

The testing of the two test vehicles has demonstrated that Imbedded Component/Die Technology (IC/DT) is a robust packaging technology for use in products that must operate in harsh environments [12]. The two test vehicles discussed in this paper have proven that the design guidelines, materials, and process parameters used to manufacture IC/DT assemblies are capable of withstanding temperature, humidity, and shock stresses.

Test Vehicle 1 (daisy-chain sample) survived over 3000 cycles of thermal shock exposure before a failure occurred. Test Vehicle 2 (mixed-signal prototype) was bench tested to meet and exceed legacy product performance specifications in order to qualify the prototypes as flight hardware. Lastly, a successfully flight test of the mixed-signal prototype in October of 2006 was paramount in demonstrating IC/DT's ability to meet form, fit, and function requirements in a miniaturized robust package.

Originally published in the Proceedings of the SMTA International Conference, Orlando, Florida, August 17-21, 2008.

Future designs requiring SWAP and hi-reliability requirements now have a design suite (IC/DT) capable of meeting their requirements for future design objectives for lighter, smaller, and less power requirements.

As shown earlier in technology prototypes, the test vehicles have proven their reliability characteristics by long term environmental testing as well as successfully being flown in actual systems. So the answer is "YES" to the question that IC/DT is now ready for mainstream design engineering / applications.