Not Just Chips: Packaging of Sensors for High Reliability, Survival and Performance in Extreme...

Packaging of Sensors for High Reliability, Survival and Performance in Extreme Environments
Nicholas Tiliakos
Innoveering-GE Aerospace
Designing sensor packaging for extreme environments (eg. high temperature, oxidizing, high pressure applications) requires understanding the environment and its underlying physics but also accounting for its effects on the sensor’s packaging material selection, design (i.e. geometry/configuration), its survivability and reliability as well as how the packaging can affect sensor performance. It is especially challenging integrating a MEMS based sensor, i.e. the die, into its packaging with electrical interconnects, ensuring their integrity and survival under these harsh conditions.
In some situations the packaging design may be sufficient for surviving in the environment but may adversely affect sensor performance and reliability over time. This talk will present analysis, some experimental data and “lessons learned” experience regarding the design, fabrication, testing and development of harsh environment sensors and their packaging, particularly for aerospace applications. The focus will be on the unique considerations of designing sensor packaging for these hostile environments, including managing thermal and pressure gradients and minimizing any adverse effects on the encapsulated sensor’s operation, reliability and survivability. To motivate and present our approach the discussion will invoke some unique case studies specific to harsh environment sensor/packaging development. Testing these sensors under relevant conditions also requires specialized test facilities to replicate the extreme aerospace environment. The authors will focus primarily on the hypersonic aero-propulsion environment, as it presents an area of intense interest, in both the civilian and military sectors, in the U.S and to the authors.