Authored By:
Leonard Allison
Engineered Materials Systems, Inc.
Summary
Polymer Thick Film (PTF)-based printed electronics (aka Printed Electronics) has improved in durability over the last few decades and is now a proven alternative to copper circuitry in many applications once thought beyond the capability of PTF circuitry. This paper describes peak performance and areas for future improvement.
State-of-the-art PTF circuitry performance includes the ability to withstand sharp crease tests, 85C/85%RH damp heat 5VDC bias aging (silver migration), auto seat durability cycling, SMT mandrel flexing, and others. The IPC/SGIA subcommittee for Standards Tests development has adopted several ASTM test methods for PTF circuitry and is actively developing needed improvements or additions. These standards are described herein. Advantages of PTF circuitry over copper include: varied conductive material compositions, lower cost and lower environmental impact. Necessary improvements include: robust integration of chip and power, higher conductivity, and fine line multi-layer patterning.
Conclusions
The problem we have solved
Robust PTF circuitry with mounted components is not only possible, but should be mandatory for the success of the industry.
What we will (or could) do next
The biggest challenge to PTF circuitry is the integration of IC chip and power. Current best practices are to integrate a copper flex circuit with the IC chip and power to the PTF circuit. Developments in printable memory, flexible power cells and highly conductive interfaces should provide answers in the future. As for the timeline for these new developments, 20 years ago it was predicted printed IC would be available today. Clearly we are not there yet. Some companies have attached IC to PTF Electronics, but it is not mainstream.
Initially Published in the IPC Proceedings
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